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1. Lee sew ewaatdoaaanae y Axis Load Factor y multiplier 1 view Curve Nodal Displacement Load Factor a co Load F actor D aa 0 64712 0 56198 1 07701 1 29221 1 5076 1 72316 1 93891 2 15485 2 37098 2 5673 2 80381 0 04 0 05 0 06 0 07 0 08 0 09 0 1 0 11 0 12 Nodal Displacement 0 13 Open Plot Settings Fig 16 The top displacement vs load factor pushover curve I ZeusNL Deformed Shape Yiewer i File Edit Tools Help Sm SR AGA a Qs l0 x l 3D Yiew J Ares J Joints h Structural Modes J Luroped Masses h Elements J Dashpots Reset Click list to view deformed shape Output Mo 96 Load Factor 0 91 Output Mo 97 Load Factor 0 92 Output Mo 98 Load Factor 0 93 Output Mo 99 Load Factor 0 94 Output Mo 100 Load Factor 0 95 Output Mo 101 Load Factor 0 96 Output Mo 102 Load Factor 0 97 Output Mo 103 Load Factor 0 98 Output Mo 104 Load Factor 0 99 Output Mo 105 Load Factor 1 Output Mo 106 Load Factor 1 00798 Output Mo 107 Load Factor 1 05221 Output Mo 108 Load Factor 1 15939 Output Mo 109 Load Factor 1 45038 Output Mo 110 Load Factor 1 52628 Output Mo 111 Load Factor 1 46454 Output Mo 112 Load Factor 1 42288 Output Mo 113 Load Factor 1 39013 Output Mo 114 Load Factor 1 36568 Output Mo 115 Load Factor 1 34818 Output Mo 116 Load Factor 1 33613 117 Load Fact
2. 0 99139 0 94041 0 88934 0 71269 0 58518 0 5707 0 4877 0 53902 0 49948 0 42749 0 3933 e fi Accelerogram E Acceleration Fig 56 Adaptive parameters page 2 13 ZeusNL User Manual After implementing the changes the adaptive pushover is ready to run The num file is very similar to a conventional pushover num file However note that three more output files are created a pat Contains the loading patterns applied to the structure at every step a per Contains a list of the modal periods at every step a mpf Contains a list of the modal participation factors at every step 4 2 Structural Gaps In order to model a structural gap in ZeusNL the joint element with the astr curve should be employed To model the gap specify zero resistance in the direction of the gap until a certain displacement is reached At that point the resistance should have a very large value i e theoretically infinite Also specify zero resistance in all the other directions For example the following parameters represent a curve with zero resistance until a negative displacement D is achieved K arbitrary value it is not important because d 4 0 d 0 K 0 d arbitrary value it is not important because both K 4 0 and K 0 K 0 Ko arbitrary value it is not important because d 0 d 0 K 0 d D K the stiffness of the curve after D is reached Ko d 4 K d K Ko d K4 d2 Kz are t
3. 4 System for Inelastic Analysis of Structures User Manual Version 1 8 9 Amr S Elnashai Vassilis K Papanikolaou Do Hyung Lee ZeusNL User Manual 1 INTRODUCTION Zeus Nonlinear ZeusNL provides an easy and efficient way to run accurate nonlinear dynamic time history conventional and adaptive pushover and eigenvalue analysis Unlike other similar analysis packages dynamic analysis is now a matter of basic simple steps using a completely visual approach This means that the user can create a structural model just by point n click and then let the program take care of all the analysis details 1 1 Technical Capabilities ZeusNL can be used to predict the large displacement behavior of plane and space frames under static or dynamic loading taking into account both geometric and material nonlinear behavior Concrete and steel material models are available together with a large library of 3D elements that can be used with a wide choice of typical pre defined steel concrete and composite section configurations The applied loading can be constant or variable forces displacements and accelerations ZeusNL has the ability to perform eigenvalue static pushover static time history and dynamic analysis as follows ZeusNL User Manual a Eigenvalue analysis The efficient Lanczos algorithm is used for the evaluation of the structural natural frequencies and mode shapes a Static pushover analysis conventional and adaptive In
4. For the time being it s only worth mentioning the target displacement of the automatic control which is the target at which the analysis stops if it hasn t stopped before due to divergence problems and the direction of the controlled freedom here it is the x direction After the termination of the analysis like in the two previous tutorials the results can be processed with the Post Processor and the Deformed Shape Viewer Fig 16 and 17 I ZeusNL C WProgram Files ZeusNL WExamples 3d_StaticPushoverAnal dat l f E3 File Edit View Define Settings Tools Run Help DEAH SR WAA lt gt 0 gt FA 5485 Materials Sections Element Classes Nodes Element Connectivity Restraints applied Loading Loading Phases x y 2 rx ry rz x y 2 rx ry rz x y 2 rxtry r2 x y z rx ry rz Delete x y z rx ry rz X y z rx ry rz Edit Plot Options IV 3D iew V Structural Nodes J Non Structural Nodes V Elements V Joints V Lumped Masses JV Distributed Masses MV Dashpots J Rayleigh Dampers JV Restraints Node Names Element Names Fig 15 The model created for pushover analysis 2 ZeusNL User Manual I ZeusNL Post Processor C 4Program Files ZeusNL WExamples W3d_StaticPushoverAnal num Oj x File Edit Yiew Tools Help eH 46Q aea Qe fag x Axis Nodal Displacement Node n151 x direction x multiplier 1
5. Number of Frames Structural Model Settings Regular Structure a Structural Type Reinforced Concrete Structure Elements per Member 2 Node Naming Convention Int 11 x1 Loading Analysis Type Dynamic Time History Analysis EJ 2D Fig 1 Template screen one structural configuration 3D frame or 2D frame Choose a 3D frame E C Number of bays stories frames Select two bays four stories and two frames a Regular structure For the time being a regular model will be used In Section 3 the option for modeling structures is discussed E Bay length story height distance between frames ZeusNL is using mm for length units choose 5000mm 3000mm or 6000mm respectively In ZeusNL length units are always millimeters and force units are Newtons ZeusNL User Manual Structural type RC or steel structures Select RC Elements per member This option determines how many elements each member column and beam will be subdivided into Select two elements per member a Node naming convention This determines the way in which the nodes are to be named The first option default yields node names easier to read Select the default a Analysis type The user can select one of the six analysis types of ZeusNL Choose dynamic time history analysis Click on the Ok button to proceed to the next step 2 1 2 Applied loading On this screen the accelerogram that will be used
6. 10000 10 Fz Fz Parameters Displacement lin 10000 di 5 Mx Mx Parameters smtr ad fo 3rd branch stifness Ke My My Parameters ion ka fo Mz Mz Parameters Cancel Fig 31 New Joint Element Class Defining curves If the user adds a new element class the details of the class will be added to the appropriate Element Class table there is a table for each of the element types available for the particular analysis type that is being run The element classes defined here are used in the Element Connectivity module to define the connectivity of the elements in the mesh configuration 3 6 Nodes Non structural nodes were discussed in Section 2 For some element types cubic joint dmass and rdamp extra nodes apart from the end nodes should be specified to define the orientation of local axes of the elements This is the only purpose that non structural nodes serve However structural nodes can also be used as the extra node It is much more simple and clear to use non structural nodes for this For a comprehensive explanation of the relation of the local element axes with the global axes refer to Appendix E Adding editing and incrementing nodes are straightforward and shouldn t be difficult or complicated However take care during incrementation not to specify nodes that 45 ZeusNL User Manual already exist Also note that the identifiers of the nodes to be incremented should be in the
7. After that if everything is correct the graphical environment is minimized and the second program which is the actual finite element analysis program runs However under certain circumstances an error may exist in the input data e g the file with the input earthquake motion may not exist or be corrupt In this case the user is informed of the occurrence of an error and is asked if they want to see a log file Answer yes and find the error message indicated with a distinctive red color Correct it and run the analysis again 4 3 3 List of ZeusNL input and output files Apart from the dat file there are two other file types that hold input data The first type is the crv file that holds the data of loaded time history curves The second type is the adt file that holds the records which will be used to derive the elastic spectrum used for scaling of the forces in adaptive pushover analysis These files should not be deleted When running a project ZeusNL creates a number of temporary files that are deleted after the completion of the analysis res cnd res lod phs ref rpr plt sbd stg Spr tmp and eig Due to their temporary nature these files are of no importance to the user 79 ZeusNL User Manual The output files are a num The file that holds the results of the analysis a nod log and out Log files that hold data about the modeled structure and the analysis itself a pat per mpf Files
8. Curvature Moment Curvature Moment Curvature Monitor 10 Moment Curvature Monitor 11 Moment Curvature Monitor 12 Moment Curvature Monitor 13 Moment Curvature Dynamic Pushover File Dynamic1 dat Monitor 1 Base Shear Vx n111 n211 n311 Drift Ux n341 to n311 sw Pe ee See ee ao Base Shear KN 0 0 05 i 2 0 25 0 35 0 4 0 45 7 Corresponding DE steps Drift m NoMarks Fores Drifts Scaling Factors Fig F1 The ZBeer main window e Input region It includes the type of analysis a list of data files scheduled to run a list of response parameters to monitor scaling factors for dynamic pushover analysis the calculation of the CCDF value and some other secondary options All these features will be presented in detail in the subsequent paragraphs e Status region The status window shows online information about the number of files run record scaling factors for dynamic pushover analysis and elapsed times e Chart region This chart depicts the analysis results shows response numeric values and features data exporting when right clicked 127 ZeusNL User Manual F 2 Theoretical background There are two types of analysis supported by the ZBeer utility Inelastic static pushover analysis in any form conventional or adaptive and dynamic pushover analysis also referred as Incremental Dynamic Analysis IDA F 2 1 Static pushover analysis This type of analysis ha
9. Materials Sections Element Classes Nodes Element Connectivity Restraints Time History Curves Applied Loading Equilibrium Stages n242 5000 9000 6000 structural n242 x1 7500 9000 6000 structural n242 y1 5000 10500 6000 structural pr an n251 5000 12000 0 structural pr n251 x1 7500 12000 0 structural Pan oe i n251 21 5000 12000 3000 structural SE ae 1 i n252 5000 12000 6000 structural ne nodes i il n252 x1 7500 12000 6000 structural naii 10000 0 0 structur je i n311 v1 10000 1500 0 structuyal f n312 10000 0 6000 structyral n312 v1 10000 1500 6000 strucfural i n321 10000 3000 0 strugtural n321 y1 10000 4500 0 str ctural i n321 21 10000 3000 3000 stfuctural Pe n322 10000 3000 6000 Fructural i n322 y1 10000 4500 6000 Structural i i n331 10000 6000 0 structural i n331 v1 10000 7500 0 structural l n331 21 10000 6000 3000 structural n332 10000 6000 6000 structural i i M Plot Options n332 y1 10000 7500 600 structural i n341 10000 9000 0 structural ior i M 3D View n341 y1 10000 10500 0 structural mid Sims 7 D Structural Nodes n341 21 10000 93000 poo structural pot i i n342 10000 9000 6000 structural Ea Non Structural Nodes n342 y1 10000 10500 6000 structural N va n351 10000 12000 0 structural i i T V Elements n351 21 10000 1i2000 3000 structural i ik An i e i n352 10000 1200
10. Mote that all the time values Curve Mame should be LARGER than zero and in ASCENDING order X cancel fervi Load Factor S m B T Le T a 3 Fig 37 The New User Defined Curve dialog box S ZeusNL User Manual The Start Time value is at the left of the main window It is the time that the analysis starts All of the time entries of the curves either loaded or user defined should be larger than not equal to the start time To edit the Start Time there shouldn t be any curves defined Usually the default value zero is fine After defining the loading pattern the applied loading that uses this pattern should be specified In the Applied Loading module select Add and define the node s where the pattern will be applied the direction the type force displacement the value with which the pattern values will be multiplied and the curve name Fig 38 New Applied Load i x Static Time History Load List of Nodes nil n141 x1 ni i yi ni l zi nitz n14z x1 Cancel Direction fy Type displacement Value Curve Mame Fig 38 New static time history load The last thing to do before running the project is to define at which time steps structural equilibrium is sought This is done in the Equilibrium Stages module More than one stage can be added if the user wants to have smaller time steps in demanding phases of the analysis To add a stage enter the
11. become z rx ry rz 36 Q ZeusNL User Manual Whenever the user tries to change analysis type the program notifies the user of the changes that happen For example if the there is a model for dynamic analysis and the analysis type is changed to static pushover ZeusNL asks the user to remove the mass and damping elements and change the boundary conditions 3 2 Basic Table Functions Most of the input data are arranged in tables in the different modules There are some standard functions that can be used with tables to increase the productivity Most of these functions were discussed in Section 2 Below is a complete list of the functionality tables that are offered Q Copying and pasting The user can copy data from or paste data to all the tables In this way ZeusNL can interact with other applications mainly spreadsheet programs such as Microsoft Excel Copying and pasting can be done either by the main menu Edit gt Copy Selection and Edit gt Paste Selection or by the pop up menus of the tables right click on the tables Note if the user try to paste data that is not in the correct format ZeusNL will generate an error message Sorting If the user clicks on the column headings ZeusNL will sort the list of items of the table according to the clicked column For example if the user clicks on the section Names Headings ZeusNL will sort the sections alphabetically If the nodal x coordinates is selected it will sor
12. up to 3 time steps inside which the maximum corresponding values are sought Figure F3 shows the above concept in detail absolute maxima hysteretic 3 curve _ o 1 i En z e ee Fig F3 Response maxima and corresponding values including a time step window In the above figure Xmax has a corresponding Yo when no step window is taken into account If a step window of 1 is considered the corresponding Ycor is the maximum ordinate of points 0 1 and 1 resulting to point Y o t1 and so forth The use of response maximum with corresponding values instead of both absolute maxima results into two series of dynamic pushover points one for the maximum X with corresponding Y values and the other for just the opposite It is noted here that in cases where the response maxima actually occur at the same time instant the use of corresponding values does not make any difference Running dynamic pushover analysis is a time consuming process but ZBeer simplifies the whole procedure by automatically scaling the input record for a series of scaling factors running the dynamic analysis for the structure under consideration collecting the requested response parameters and plotting the dynamic pushover points Moreover the above procedure can be run for many structures at a time just like in the static pushover case resulting to even thousands of dynamic analyses by the press of one button 129 Zeus
13. Concrete C30 Static4 dat Dynamic4 dat Concrete C40 Static5 dat Dynamic5 dat Concrete C50 Moreover a record file LomaPrieta rec used by dynamic analysis and an already prepared monitors file for ZBeer Monitors mon are included Monitors include a base shear global drift monitor story shear interstory drift monitors for all three stories and nine moment curvature monitors of all column bases The user can test the performance of ZBeer by running several static and dynamic pushover analyses for these structures collect the output files in the form of Dynamic1 psh Dynamicd psh Static1 psh Static5 psh and create comparative plots using a spreadsheet program like Microsoft Excel Finally comparison between static and dynamic analysis can be carried out using the PP utility of ZBeer Figure F15 shows a completed comparative plot of all ten structures for the base shear global drift monitor 146 Base shear KN ZeusNL User Manual Variable Concrete Strength Regular Structure Three Story Two bay 800 700 600 Static C50 o Dynamic C50 500 400 7 ight 9M Static C12 x o Dynamic C12 a Static C20 ii is o Dynamic C20 Static C30 200 o Dynamic C30 z Static C40 e o Dynamic C40 100 i 0 0 05 0 1 0 15 0 2 0 25 0 3 0 35 0 4 0 45 0 5 0 55 Global drift m Figure F15 Comparative plot of structures with variable material strength 147
14. Manual astr Tri linear asymmetric elasto plastic curve type Number of parameters 10 2 5 It is similar to the smtr tri linear elasto plastic curve but it is asymmetric Hence 10 parameters are required for the complete description of the curve Unloading is done kinematically to the extension of the second branch of the curve All the stiffnesses K K K and Ko Ky K2 must be positive and K and K2 should be less than Ko both for the positive and negative displacement region The curve models the elasto plastic joint action and because it is asymmetric it can also model structural gaps parameter Description typical value Initial stiffness positive displacement region Positive displacement where the stiffness changes from Ko to K 4 Stiffness of second branch positive displacement region Positive displacement where the stiffness changes from K to K 2 Stiffness of third branch positive displacement region Initial stiffness negative displacement region Negative displacement where the stiffness changes from Ko to K 4 Stiffness of second branch negative displacement region Negative displacement where the stiffness changes from K to K2 Stiffness of third branch negative displacement region 117 ZeusNL User Manual force P K d i i d displacement 118 ZeusNL User Manual hsc Hysteretic shear model under constant axial force Shear force v LAK A A An She
15. Output Wo 966 Time 8 1832 Output Mo 967 Time 3 154 Output Wo 968 Time 8 188 Output Wo 969 Time 8 192 Output Mo 970 Time 8 196 Output No 971 Time 8 2 Output Mo 972 Time 8 204 Output Wo 973 Time Fig 11 Deformed Shape Viewer dynamic analysis The options on the top left corner of the window are already familiar as well as the Tools gt 3D Plot Options dialog box They allow the user to quickly change the appearance of the plot before printing or copying it One interesting parameter is that the Deformation Multiplier Tools gt Settings is the parameter by which the nodal deformations are multiplied before the plot is derived 23 ZeusNL User Manual 2 2 Tutorial 2 Eigenvalue analysis The dynamic analysis has been run with the four story structure but in order to obtain the dynamic characteristics of it i e eigenperiods and mode shapes an eigenvalue analysis needs to be run There are two possible ways of doing this The more vigorous would be to alter the existing model for the needs of eigenvalue analysis However the potential problems that could arise when changing from one analysis type to another will be dealt with in Section 3 The second way is to create a new identical structural model from the template Select File gt Create from Template and specify the same structural characteristics with the previous example but now choose eigenvalue rather than dynamic analysis There are a
16. advance features presented hereafter 4 1 Adaptive Pushover Procedure 4 1 1 Theoretical background One of the main deficiencies of conventional pushover analysis is its inherent inability to account for the progressive stiffness degradation that occurs during the cyclic non linear earthquake loading Consequently the changes in the modal characteristics the period elongation and the different spectral amplifications cannot be considered The fixed nature of the load distribution applied to the structure which ignores the potential redistribution of forces during the procedure does not allow for the capturing of these characteristics that are of great significance in an inelastic time history analysis Moreover the deformation estimates obtained from a pushover analysis may be highly inaccurate for structures where higher mode effects are significant 70 ZeusNL User Manual A new refined approach which takes into account the current stiffness state of the structure at each step and higher mode effects is expected to yield more accurate results than the conventional pushover Such procedure is ZeusNL Adaptive Pushover Procedure In the adaptive pushover approach the lateral load distribution is not kept constant but is continuously updated during the analysis according to the modal shapes and participation factors derived by eigenvalue analysis carried out at the current step The new method is fully multi modal and accounts for pe
17. an item e g a node in drop down lists with hundreds of items If the name of the item node is known start typing the name when the list is active and ZeusNL will find it After selecting both x and y the user can view the curve with the View Curve button The values of the plot are shown on the table at the bottom left corner I ZeusNL Post Processor C Wtemp modell num i JO x File Edit wiew Tools Help Ass Time x multiplier 1 VAIS Interstorey drift g Modes ni51 and n111 x direction v multiplier 1 View Curve 0 00356 0 02 0 004 Interstorey drit 0 06 0 00964 0 08 0 00504 O 1 0 02159 Ole 0 073 0 14 0 12837 0 16 0 14796 0 16 0 07043 Oe 0 16344 O22 0 5466 O24 1 02077 0 26 1 56695 Fig 47 ZeusNL Post Processor 65 ZeusNL User Manual The diagram and corresponding values can be copied to other word processing or spreadsheet programs To change the appearance of the diagram before copying it line color thickness background axes values etc open the Options dialog box Tools gt Options The process is very straightforward The user can also zoom in and out with the menu commands toolbar buttons or by selecting a specific area a top left to bottom right selection zooms in whereas a bottom right to top left selection zooms out 3 12 1 1 Post Processor settings Select Tools gt Settings to display the settings The user
18. couple of changes in this current model in comparison with the first dynamic analysis model a There are some modules missing Time History Curves Loads and Equilibrium Stages All of these are related to the applied loading and therefore are not needed for eigenvalue analysis a The x DOF of the supports that has been released for the dynamic analysis is now restrained Apart form these differences the models should be identical Save the project and run it After the analysis has been completed because its eigenvalue analysis it should not last more than a few seconds open the deformed shape viewer and open the analysis num file A list of the converged eigenmodes will appear Select each one of them and click the View Shape button to see the mode shapes Fig 12 Again the user can easily copy print or change the appearance of the created 3D plot 24 ZeusNL User Manual I ZeusNL Deformed Shape iewer Ioj xj File Edit Tools Help l SBR ASB eas V 3D iew Jw Axes J Joints Jw Structural Modes fx Lurnped Masses fw Elements fw Dashpots Reset Click list to view deformed shape Output No l Modal Period 0 67959 Output No 2 Modal Period 0 5197 Output No 3 Modal Period 0 54122 Output No 4 Modal Period 0 23266 Output No 5 Modal Period 0 1765 Output No 6 Modal Period 0 18515 Output No 7 Modal Period 0 14813 Output No 8 Modal Period 0 11925 Output No 9 Mod
19. created during adaptive pushover analysis They hold data about the loading patterns the modal periods and the modal participation factors at every step These files can be useful in many ways to the user Also note if the autosave function is activated this is the default a back up bak file of the dat is being saved at regular intervals 80 ZeusNL User Manual Appendix A Materials In this Appendix a list of the available ZeusNL material types is presented Q 0D CO O0 O0 U CO U DO DO stl1 stl1 stl2 stl3 con1 con2 con3 con4 ecc frp1 Linear elastic model Bilinear elasto plastic model with kinematic strain hardening Ramberg Osgood model with Masing type hysteresis curve Menegotto Pinto model with isotropic strain hardening Trilinear concrete model Uniaxial constant confinement concrete model Uniaxial variable confinement concrete model Sheikh Uzumeri model Model for Engineered Cementitious Composite ECC materials Uniaxial constant fiber reinforced plastic confined concrete model 81 ZeusNL User Manual stlO Linear elastic model Number of properties 1 This model is applied for the uniaxial modeling of mild steel typical value property description 200000 E The Young s Modulus Stress 5 Strain E 82 ZeusNL User Manual Stl 1 Bilinear elasto plastic model with kinematic strain hardening Number of properties 3 This model is applied for the uniaxial modeling of mild
20. data are specified After the completion of the model the program focuses on the Nodes page and the structure appears The screen will look like Fig 3 I ZeusNL C 4temp modelli dat lol x File Edit View Define Settings Tools Run Help YAN ar a b s 1 DSOHE SR dB lt C gt oe FA ag Materials Sections Element Classes Nodes Element Connectivity Restraints Time History Curves Applied Loading Equilibrium Stages Type structural structural structural structural structural structural structural structural structural structural structural structural structural structural structural structural structural structural structural structural structural structural structural structural structural structural structural structural structural structural structural structural structural JV Distributed Masses structural structural V Dashpots i i structural structural structural JV Restraints structural structural Node Names i i structural structural J Element Names structural Dynamic Time History Analysis Edit Delete Incrementation Move itet e e e e A EN Plot Options V 3D Yiew V Structural Nodes on o o Non Structural Nodes JV Elements N Oo uw o Oo JV Joints ol o D V Lumped Masses IV Rayleigh Dampers Defined Nod
21. define six curves three in longitudinal and three in transverse direction In this case user can define the curve number as 1 to 6 corresponding to each direction of each pier The second and the third row of the second column represent the axial force capacity in compression and in tension respectively these values should be positive The third column represents Flexural displacement at cracking corresponding to each level of axial force defined in the first column The fourth column represents Flexural displacement at yielding corresponding to each level of axial force defined in the first column The fifth column represents Flexural displacement at ultimate corresponding to each level of axial force defined in the first column The sixth column represents shear force at crack corresponding to each level of axial force defined in the first column The seventh column represents shear force at yielding corresponding to each level of axial force defined in the first column The eighth column represents shear force at ultimate corresponding to each level of axial force defined in the first column For the parameters of the curve type hfv monotonic shear force flexural displacement curve subjected to each level of axial force defined has to be evaluated in advance 122 ZeusNL User Manual Appendix E Local and Global axes Appendix E is a discussion about the extra node for defining the orientation of the elemen
22. format word number e g n111 and nod20 The word can be omitted and only numbers can be used for identifiers e g 22 and 44 If the user tries to increment a node called n111 y1 an error message will appear indicating that the node cannot me incremented since it s not on the correct format Node and element identifiers have to be in the correct word number or number format to be incremented 3 Element Connectivity Each element defined here belongs to a specific element class and depending on element type of the class it may have one Imass ddamp three cubic dmass rdamp or four nodes joint The third for cubic dmass rdamp or fourth for joint node may be a non structural node Again adding editing incrementing or subdividing nodes is not difficult Remember a in incrementation the new element identifiers are unique and the end nodes of the elements already exist a only linear elements cubic dmass rdamp are subdivided One feature that the user will probably find very useful is the ability to change the element class of a large number of elements in one step by making a multiple selection and clicking Edit This is very handy when for example the user want to the change the beams element of one story from one element class to another 3 8 Restraints To change the boundary conditions select one or more nodes and in the Restraints dialog box specify the restrained freedoms N
23. get an impression of what this file looks like if any file created by ZeusNL is opened with a simple text editor like Microsoft WordPad The user can also see the dat file of the project that is being built from the View gt Open Data File menu command The user will notice many similarities between ZeusNL tables and the dat file All the data are organized in modules different module for the section types the nodal co ordinates the element connectivity etc These modules are identified by the program by a unique header e g Sections Materials Element Classes Structural Nodal Coordinates Element Connectivity Restraints Applied Loading etc The headers correspond very closely to the headers of ZeusNL modules The user should have no problems in understanding how the input data are arranged in the dat file There are however a couple of things that the user should pay attention to a Some of the secondary dat file modules are defined in ZeusNL Settings e g the Integration Parameters or the Iterative Strategy modules a The Phases module has an unusual path parameter Moreover the automatic control phase is of nod control translation type and there is a condition name parameter The condition is defined in a completely new module called Conditions with no correspondence in the graphical environment The path parameter specifies the sign of the applied load increments keep keeps the same sign of increment continue fol
24. joint element forces the stresses of the monitoring points and the support forces of a large number of nodes elements or supports on a table Then the read data can easily be copied to spreadsheet programs e g Microsoft Excel Select the type of data to read and the nodes or elements of interest and click the Read Data button The program starts reading the num output file and prints the required values on the table on the right 3 12 2 Deformed Shape Viewer With the Post Processor the user can easily create diagrams from an analysis With the deformed shape viewer Tools gt Deformed Shape Viewer the user can see the deformed shape of the model at different steps of the analysis Load the results num file of the project A list of the steps time steps for time history analysis or loading steps for pushover analysis or the modes eigenvalue analysis appears on the window To display the deformed shape at one of these steps select it and click the View Shape button The derived deformed shape can be then easily copied or printed I ZeusNL Deformed Shape iewer k Ioj x File Edit Tools Help aw G Sa ASB s amp s Time 8 12 sec l 3D View l Axes Jw Joints J Structural Modes J Lumped Masses l Elements Jw Dashpots Reset Click list to wiew deformed shape Output Wo 950 Time 8 068 Output Wo 951 Time 8 072 Output Wo 952 Time 8 076 Output Wo 953 Time 8 08 Output Wo 9
25. list of the available ZeusNL element types Note some element types are not available for particular analysis types e g mass and damping element types Imass dmass ddamp rdamp are not available in static analyses Selecting an element type from the drop down menu opens the appropriate lists and textboxes for the user to specify the element properties For example if a cubic type is selected the New Element Class dialog box will appear as in Fig 29 and the user has to specify the section for the new cubic element class and the monitoring points in which the section is divided 42 ZeusNL User Manual New Element Class B x Element Class Name class Cancel Element Class Type cubic 3D cubic elasto plastic beam column element Section Mame Monitoring Points sect 200 Specify Birth and Death Time Birth Time m oOo Death Time me oO Fig 29 New cubic Element Class For Imass the concentrated mass must be specified for dmass the distributed mass must be specified for ddamp the six damping parameters C C C Cx Cyy and Cz must be specified and for rdamp a section name the mass length value and the two damping parameters a1 and a2 must be specified The situation is more complicated for the joint element Fig 30 43 ZeusNL User Manual New Element Class i X Element Class Name ficlass Cancel Element Class Type joint 1 3D joint element Fx Fx Parameters lin z 10000 F
26. materials defined in the Materials module 1 for steel sections and 3 through 4 for RC and composite sections The user can define an infinite number of sections to be used to define element classes Each section has a unique name can be copied pasted and edited Reinforcing bars may be added only to RC sections The bars should be positioned within the confined region of the section The reinforcing bars are arranged on the Section Reinforcement table of the Main Program window in trinities of As d3 d4 Since the sections are symmetrical only the bars of the positive 1 3 quadrant have to be specified especially for T sections the bars in the positive 1 side of the section should be specified The rest of the bars are generated by the program 40 ZeusNL User Manual 3 5 Element Classes The ZeusNL element library includes a set of element types used to model structural elements beams and columns non structural elements mass and damping and boundary conditions Supports and joints a Cubic Cubic elasto plastic 3D beam column element It is used for detailed inelastic modeling making use of the uniaxial inelastic material models described above It accounts for the spread of inelasticity along the member length and across the section depth Q Joint 3D joint element with uncoupled axial shear and moment actions This element is used to model pin joints inclined supports elasto plastic joint behavior soil struc
27. steel property description typical value The Young s Modulus 200000 Yield Strength 500 Strain hardening parameter 0 005 i Strain 83 ZeusNL User Manual stl2 Ramberg Osgood model with kinematic strain hardening Number of properties 4 This model is applied for the uniaxial modeling of mild steel Stress Strain Relationship O O i a Es property description typical value The Young s Modulus 200000 Material constants determined by a best fit procedure using the available experimental data The parameter b is assumed as a yield stress After this yield point the model will follow the Masing type unloading or reloading hysteresis curves Strain E 84 ZeusNL User Manual stl3 Menegotto Pinto model with isotropic strain hardening Number of properties 8 This model is applied for the uniaxial modeling of mild steel property description typical value Yield stress 500 Initial elastic modulus 200000 Strain hardening modulus 2000 Q lt ea ais Parameter defining the initial loading curvature 20 Experimentally determined parameters controlling 18 5 the curvature in subsequent cycles 0 15 N Experimentally determined parameters controlling 0 01 the isotropic strain hardening in subsequent cycles 7 o o 2 D 0S K Using the default values for the parameters Ro a1 a2 a3 and a is highly recommended unless user has e
28. the user right clicks on parts of the ZeusNL windows These menus allow for fast and easy execution of the most commonly used functions Pop up menus are attached to all the ZeusNL tables and diagrams 1 4 What is Included The program is delivered as an installation executable ZeusNL lt version number gt Setup exe There is a time limit on the program until the end of the current year 1 5 System Requirements The following table depicts the requirements for using ZeusNL Part Requirement Processor Pentium III or higher RAM 64 MB or higher 128 MB recommended Hard Disk 11 MB of free space for the installation however running projects with large models hundreds of nodes especially in time history analysis may result in extremely large output files sometimes more than 100MB Video adapter Windows operating system supported graphic adapter minimum resolution 1024x768 Operating System Windows 95 98 Windows Me Windows NT Windows 2000 Windows XP ZeusNL User Manual 1 6 Installing ZeusNL Start up the Windows operating system Insert ZeusNL installation CD ROM into the CD drive Normally the setup program will start automatically If not open the CD ROM contents and run the Setup executable 4 Follow the instructions and the automated installation program will proceed to copy ZeusNL onto the hard drive Normally the default settings suggested by the installation should work well ZeusNL shortcuts w
29. the z beam starting from node n121 are n121 z1 n121 z2 etc and the nodes on the y column starting from node n121 are n121 y1 n121 y2 etc This convention is clear but it has the disadvantage that the nodes of the columns and the beams are not in the format word number and therefore cannot be incremented However the template is so powerful and flexible that the user probably won t need incrementation and this convention is the default n101011 All the node numbers at the beam column joints are of the format n 10i 10j 10k where i is the column number starting from the left j is the story number starting from the bottom e g n102010 is the node n121 according to the previous convention and k is the frame number starting from the front The nodes on the x beam starting from node n121 are n112010 n122010 etc the nodes on the z beam starting from node n121 are n102011 n102012 etc and the nodes on the y column starting from node n121 are n102110 n102210 This convention is not very clear especially when the user has a large number of nodes However it allows for incrementation of the nodes since they are in the correct word number format The choice of the naming convention is completely up to the user and the needs of the particular project that is running However note if one element per member is selected this option has no meaning since in both cases the node identifiers are derived by the n i
30. these types the user can create an infinite number of materials that will be used to define sections The four material types are a stlO Linear elastic model This model is applied for the uniaxial modeling of mild steel One parameter is required The Young s Modulus a stl1 Bilinear elasto plastic model with kinematic strain hardening This model is applied for the uniaxial modeling of mild steel Three parameters are required The Youngs Modulus yield strength and strain hardening 38 ZeusNL User Manual stl2 Ramberg Osgood model Power Law with Masing type hysteresis curve This model is applied for the uniaxial modeling of mild steel Four parameters are required The Youngs Modulus Three other material constants determined by a best fit procedure using the available experimental data cont Trilinear concrete model This is a simplified uniaxial concrete model Tension resistance and confinement effects are not included Four parameters are required initial stiffness compressive strength degradation stiffness and residual strength con2 Nonlinear concrete model with constant active confinement modeling Accurate uniaxial concrete model based on the work by Mander et al 1988 A constant confining pressure is assumed taking into account the maximum transverse pressure from confining steel This is introduced on the model through a constant confinement factor used to scale up the stress strain relationship
31. throughout the entire strain range Further the cyclic rules were significantly improved by Martinez Rueda and Elnashai 1997 to enable the prediction of continuing cyclic degradation of strength and stiffness as well as better numerical stability under large displacements analysis Four parameters are required compressive strength tensile strength crushing strain and confinement factor con3 Nonlinear concrete model featuring variable passive confinement modeling and uniaxial concrete model similar to con2 including the advanced variable confinement model developed by Madas and Elnashai 1992 The latter calculates and continuously updates the transverse confinement stress for a given applied axial strain of an RC member under cyclic or transient loading Thus in addition to concrete compressive strength the characteristics of confinement detailing such as diameter of stirrups their spacing and yield strength confined core area and Poisson ratio have also to be introduced to fully define the material model Ten parameters are required concrete compressive strength concrete tensile strength concrete crushing strain Poisson s ratio of concrete yield stress of transverse steel Young s modulus of transverse steel strain hardening parameter of transverse steel diameter of stirrups spacing of stirrups and diameter of concrete core con4 Sheikh Uzumeri nonlinear concrete model This model can consider the effect of effectiv
32. time of the end of the stage and the number of steps The time step is calculated by ZeusNL as the difference between the end time 53 ZeusNL User Manual of the current stage and that of the previous stage divided by the number of steps of the current stage For the first stage the difference between the end time of it and the Start Time defined at the Time History Curves module is utilized New Loading Stage x a Ok End of Stage fio Cancel Ca Fig 39 Adding a new stage 3 9 4 Applying loads for dynamic time history analysis As for the static time history analysis the user must define a new curve Usually this curve is an accelerogram In the Time history Curves module select Load which opens the New Curve from File dialog box Choose the reading parameters columns of time and acceleration in the file first line and last line to be read and load the curve with the Select File button Note accelerograms that are not in table format data in columns are not supported and have to be transformed before being used 99 of the existing accelerograms are in table format If the user is not sure about the reading parameters the View Text File button opens a text file for examination After the accelerogram has been loaded the user can copy or print the values and the plot pop up menus Moreover to change one of the input parameters e g if the user decides that only the first 1500 lines are needed and
33. yield a smooth animation Changing the settings results in an approximate size of the derived AVI file When creating AVI animation files try to keep their size as small as possible Try to keep the file size up to 50 of the RAM memory 68 ZeusNL User Manual AYI file settings Initial Time Step Output Mo 545 Time 6 Final Time Step Output N0 852 Time 7 5 Frequency f2 gt Uncompressed AWI size 128 08 MB Video compression no Compression Options fif available Cancel Fig 50 AVI file settings The whole process could last up to some minutes depending on the size of the derived file The movie can be viewed with the File gt Show AVI File command Note AVI files can also be opened by other applications such as the Windows Media Player or Microsoft PowerPoint to be inserted into presentations Fig 51 4 storey building subjected to the Taiwan earthquake sample record 1 movie of the structural response between 5sec 8 5sec Fig 51 Microsoft PowerPoint presentation playing a dynamic analysis movie created by ZeusNL 69 ZeusNL User Manual 4 ADVANCED SUBJECTS This chapter will present some more advanced subjects such as the new Adaptive Pushover Procedure the modeling of structural gaps and the input and output ZeusNL files The user will need to be familiar with the subjects described in the previous chapters in order to understand and use the
34. 4 The elements of the front frame namely col111 bmx121 and col211 all use nsn1001 as the third node In the same way the elements of the back frame col112 bmx122 col212 use nsn1002 The beams in the z direction bmz121 and bmz221 use ns1101 and ns1102 respectively In the special case of 2D analysis only one non structural node is required as in Fig E5 124 ZeusNL User Manual t Classes Nodes Element Connectivity Restraints Element Number Element Class 8500 BE bmx121 beam ni i n 2l1 nsni001 sooo l bmz121 beam nlzl niz nsniiol bmx122 beam niz2 1222 nsn1002 i bmz221 beam n 2l n 22 nsniiol F000 4 2 callii col nili ni i nsni001 eson JR colli col niiz niz nsniooz col211 col n211 n221 nsn1001 6000 an col212 col n2l2 n 22 nsn1002 sco d massl2i massi nizi sooo e a bet be be massi z massi nize ane cae ee es re GE 7 colti1 fl masszz1 massi n221 EOE pa h e jer r A regs masse222 massi nzz 4000 t4 Ta a e a i Line a 3500 4 3000 4 2500 47 2000 i 1500 4 1000 500 Pee Oe ee 6000 2000 ere Pe ee ae 8000 e000 ee 2 10000 10000 DE sane 123000 Element Number Element Class bmx121 beam ni i nzzi nsni001 bmz121 beam nl 1 nize nsn1101 bmx122 beam nize nz22z nsn1002 bmz221 beam n 2l n nsni101 colli1 col mili mizi mnsni i colli col nliz nize nsn1002 colz11 col nzli nzgzi nsni1001 col212 col n2l2 ngze nsn1002 masslzl1 mass 1 nlzi mas 122 massi nize masse 1 mass 1 nzel mMass
35. 54 Time 8 084 Output Wo 955 Time 8 088 Output Wo 956 Time 8 092 Output Mo 957 Time 8 096 Output No 958 Time 841 FOUEDUE MO ISS Times d2 Output No 960 Time 8 14 Output No 961 Time 8 16 Output Wo 962 Time 8 18 Output Wo 963 Time 8 1508 Output Wo 964 Time 8 1516 Output Wo 965 Time 8 1824 Output Mo 966 Time 8 18352 Output Wo 967 Time 8 184 Output No 968 Time 8 188 Output No 969 Time 8 192 Output No 970 Time 8 196 Output Noord Time 8 2 Output No 972 Time 8 204 Output Mo 973 Time 8 208 Fig 49 Deformed Shape Viewer 67 ZeusNL User Manual With the options on the top left corner the user can quickly change the appearance of the 3D plot For more advanced options and full control over the diagram select Tools gt Plot Options 3 12 2 1 Deformed Shape Viewer settings Select Tools gt Settings to display the Settings dialog box The two available options are a Deformation Multiplier This is the value with which the nodal displacements are multiplied The purpose of this setting is to exaggerate the deformation in order to have a better insight of the deformed shape a Fix position of the first node This setting is useful for dynamic analysis If checked the first node is always fixed to the same position The purpose of this setting is that the DOF of the supports in the direction s of the earthquake should be released This means t
36. 600 s00 1000 1200 J Element Names Fig 21 Model nodes t Classes Nodes Element Connectivity Restraints Time History Cur 1 wall i 2 100 2 wall 2 3 100 3 wall 3 4 100 4 wall 4 5 100 5 wall 5 amp 100 z wall 6 7 100 7 wall 7 8 100 E wall 8 9 100 z wall 9 10 100 il wall 10 11 100 Fig 22 Model elements 31 ZeusNL User Manual Automatic Incrementation x Element Increment aA o o ode Increments Increment of node 1 Cancel f Increment of node 2 Increment of node 3 _ Repetitions 9 E Fig 23 Using automatic incrementation to derive elements 2 10 from element 1 t Classes Nodes Element Connectivity Restraints Time History Curs Node Number bY ETE NEY TPZ 2 rxtry z rx ry 2 retry 2 rxtry 2 rxtry 2 rxtry z rx ry Srey z rx ry z rx ry e 0 0 a CM E G Ry rr 0 Fig 24 Model restraints The next step is to determine the load applied to it which consists of a constant vertical force and a variable horizontal displacement at node 11 First describe the pattern for the horizontal load This is done in the Time history Curves module Select Create a Curve which takes the user to the New User Defined Curve dialog box Specify the pseudo time and load factor coordinates on the table as well as the name of the curve Fig 25 and click Ok 32 ZeusNL User Manual Edit Used Defined Time History Curve X Mote that all the time values Curv
37. 6000 structural P JV Joints nsn1001 15000 1500 0 non structural 4 Dani 7 Lumped Masses nsn1002 15000 15000 6000 non structural i nsn1101 0 15fo00 12000 non structural i V Distributed Masses nsn1102 5000 12000 12000 non structural nen H om UDD Atala HEE JV Dashpots structural structural structural structural structural structural structural structural J Rayleigh Dampers V Restraints J Node Names 9 9 9 9 9 9 9 9 Element Names Structure 3D Plot Fig 8 Nodes generated with the automatic incrementation facility The Automatic Incrementation facility for the Nodes Element Connectivity and Applied Loading modules is a very powerful ZeusNL tool that enables the user to generate a structure easily and efficiently within minutes However there is one restriction with the identifiers of the nodes or elements that can be incremented they have to be in the format word number e g n111 and nod20 or the word can be omitted and only numbers may be used for identifiers e g 22 and 44 If the user tries to increment the n111 y1 node there will be an error message indicating that the node cannot me incremented since it s not on the correct format Node and element identifiers have to be in the correct word number or simply number format to be incremented For the time being since the extra nodes aren t needed either remove them or Edit gt Undo the
38. NL User Manual F 3 Using ZBeer After starting ZBeer the user has to select between Dynamic Pushover and Static Pushover mode by pressing the corresponding button If any monitors or results exist from previous analyses they will be deleted F 3 1 The File List After selecting the type of analysis data files have to be added in the files list This is done by pressing the Open data file button and select the data files for analysis which of course have to comply with its type static or dynamic Adding files from different directories is also possible by Dynamics dat following the above procedure as many times as needed Extra attention has to be paid with dynamic analysis though because all the associated record files have to be present in their original directories If the original directory of the record file needs to be changed this can be done either from the ZeusNL core program edit the time history curve or by manually editing the following line inside the dynamic analysis data file from Do NOT change the commented line below C Program Files ZeusNL ZBeer Examples LomaPrieta rec 1 2 1 500 to Do NOT change the commented line below lt new path gt LomaPrieta rec 1 2 1 500 In case of any mistake during the file addition procedure the program can be reset by pressing the New session button on the left of the open button The button on the right is for calculation of the Capacit
39. a better understanding of the procedures and the theoretical background behind them 3 1 Analysis Types 3 1 1 Eigenvalue analysis The Lanczos algorithm is used for the evaluation of the structural natural frequencies and mode shapes The number of required modes and a range of frequencies of interest are specified by the user in the program settings Tools gt Settings 3 1 2 Static analysis constant loading The applied load P is kept constant The program performs the solution of the analysis in a single step and outputs the nodal displacements and the support and element forces 35 ZeusNL User Manual 3 1 3 Static Pushover analysis The applied variable load P is kept proportional to the pattern of nominal loads P initially defined by the user The load factor 4 is automatically increased by the program until a user defined limit or structural failure is reached P P 3 1 4 Adaptive pushover analysis In this revolutionary development the load distribution of the procedure is not kept constant but is continuously updated to take into account the stiffness degradation and period elongation of the system and higher mode effects This is achieved by carrying out eigenvalue analysis at the different steps considering the current stiffness distribution at that step The subject will be covered in Section 4 3 1 5 Static time history analysis In static time history analysis the applied loads can vary independentl
40. absolute maxima Static Pushover File Static2 dat Monitor 1 Base Shear Vx n111 n211 n311 Drift Ux n341 to n311 Base Shear KN 0 25 s 0 4 0 45 0 5 0 55 Drift rn No Marks Forces Drifts Load Factors Figure F11 Static Pushover results 140 ZeusNL User Manual On the bottom and left side of the chart window there are some radio buttons which activate chart marks such as Forces Moments Drifts Curvatures and Scaling Load factors depending on the type of analysis and the type of the active monitor These marks are depicted upon each dynamic pushover point or static load step and can be better read by zooming in the chart figure F12 Drifts Load Factors No Maks C Drifts Figure F12 Chart marks For Dynamic Pushover only there are two available views of the outcoming results The default view is the pair of absolute maxima for each scaling factor red dots and the alternative is the maximum versus corresponding values including a user defined time step window refer to paragraph F 2 2 and fig F3 for more details As already explained in the theoretical part of this chapter when corresponding values are used two result series are calculated instead of one The first is the maximum X versus corresponding Y values X stands for displacement or curvature and Y for force or moment which is depicted by a green normal triangle 4 and the second is just the opposite depicted by a green inver
41. ad distribution is updated at every step o Type of loading Total or incremental loading Incremental loading means that only the increment of forces applied at each step are scaled This increment is added to the existing forces that remain unchanged In contrast total loading means the forces already applied to the structure are scaled as well Total loading yields slightly better results and is the default o Modal Combination method SRSS CQC or absolute summation absolute summation could be very inaccurate and should be avoided o Displacement limit condition The adaptive pushover phase finishes when the displacement of the selected node in the specified direction exceeds the maximum or minimum limits o Spectral amplification There are three options Do not consider spectral amplification In this case the scaling depends on the modal characteristics of the structure only Given accelerogram The scaling takes into account the elastic spectrum of a specified record Loading the accelerogram is straightforward The user can use the Accelerogram button to see the shape of the record 74 ZeusNL User Manual User defined spectrum The coordinates of the spectrum are given in a table by the user This option can be used to introduce code defined spectra I ZeusNL C 4tempWtut4_AdapStaticTimeHistAnal dat O x static Adaptive Pushover Analysis gt A 9 Materials Sections Element Classes Nod
42. al con4 Sheikh Uzumeri nonlinear concrete model Number of properties 8 concrete compressive strength steel compressive strength strain corresponding to maximum stress in plain concrete ratio of the volume of total lateral reinforcement to the volume of core center to center distance of outer tie tie spacing number of longitudinal bars and area of one longitudinal bar This model is applied for the simplified uniaxial concrete model for square sections with uniformly distributed longitudinal steel Stress Strain relationship OA gt O 4s e e sl AB gt oF f E SESE i I i i i i i i i i i i i 89 ZeusNL User Manual ECC Model for Engineered Cementitious Composite ECC materials Number of properties 9 typical value property Description Young s modulus First cracking strain Strain at peak stress in tension Strength in tension Tensile strain capacity Strain at peak stress in compression cp lt 0 Strength in compression Oep lt 0 Ultimate strain in compression cu lt 0 This value should always be less than the maximum compressive strain expected during analysis Stress on the compression envelope corresponding to Ecu Ocr lt 0 nigis ER i It n 2 le e i i ERE a Compression 90 frp1 Trilinear FRP model Number of properties 4 property Description Initial stiffness Tensile strength Degradation stiffne
43. al the dialog window G fo Cb Figure F8 Element moment versus section curvature monitoring Next the element to be monitored must perae be defined by entering its name and pressing the Add element button If it is wrongly entered it can be removed by pressing the Delete element button Note that only one element can be monitored in this monitor type Base Shear Britt Story Shear Drit te Moment Curvature There are four different moments that can be selected My and Mz both for left and right element ends My stands for the moment around the 1 axis usually strong axis of the element and Mz around the 3 axis of the element not applicable for 2D structures The left end coincides with the element start node or the origin of its 2 axis and the right end with the destination node or the end of its 1 axis Refer again to appendix E for more details on the element orientation The final step is the selection of the strain level where the curvature will be measured Every section type consists of one up to four different materials Table F1 lists all the available sections in ZeusNL with the corresponding material number This material number for which the strain level will be monitored has to be selected in the provided editbox Extreme attention must be paid to the Section Width editbox The user should provide the distance between the top and bottom strain level corresponding
44. al Period 0 11049 Output No 10 Modal Period 0 11832 Fig 12 Deformed Shape Viewer eigenvalue analysis Open Template X Reference Dimensions Bay Length mm 5000 Storey Height mm 3000 Distance between Frames 6000 Number of Bays f Number of Storeys f4 E Cancel Number of Frames jz Structural Model Settings Regular Structure r 3 D Structural Type Reinforced Concrete Structure Elements per Member lz Mode Naming Convention ni 11 x1 Loading 2 D nalysis Type Static Pushover Analysis Loading Type Uniform distribution Fig 13 Template screen one pushover analysis 25 ZeusNL User Manual Maximum Nominal Proportional Load Top node nominal proportional load ji 00234 OF Cancel Fig 14 Template screen two pushover analysis 2 3 Tutorial 3 Pushover Analysis The ZeusNL template will be used to create a model of the building for pushover analysis Selecting Static Pushover Analysis as the analysis type a new drop down list appears asking the user for the distribution of the proportional loads uniform or triangular Select the default which is Uniform Fig 13 Click Ok and a new dialog box appears where the target value of the proportional loads applied at the different stories is specified Fig 14 The main differences between the current model and the model previously created for dynamic ana
45. and frames reference length of bays height of stories and distance between frames and regular or irregular structure Everything is straightforward apart from the regular irregular option In the tutorials only used regular models were used Choosing an irregular structure and clicking Ok takes the user to a window similar to Fig 44 The length of each bay is equal to the reference bay length times the bay length ratio Therefore the length of the first bay is 9 000mm 5 000x1 8 and that of the second bay is 4 000mm 5 000x 8 The irregular model is shown in Fig 45 The procedure is similar for different story height or distances between frames a One two or four elements per structural member When two elements are selected the members are divided in two equal elements For four elements the length of the end elements is determined in the ZeusNL settings Tools gt Settings 60 ZeusNL User Manual a Node naming convention O n111 x1 All the node numbers at the beam column joints are of the format n i j k where i is the column number starting from the left j is the story number starting from the bottom ground nodes have a j 1 not j 0 and k is the frame number starting from the front For example n132 is the node at the left column of the model i 1 at the second story j 3 third level of nodes and at the second frame k 2 The nodes on the x beam starting from node n121 are n121 x1 n121 x etc the nodes on
46. ar deformation or 1 1 i 1 1 Flexural deformation i i Initial shear stiffness Ko Shear displacement at cracking Ac Shear force at cracking Ver Shear stiffness after cracking K Shear displacement at yielding A Shear force at yielding Vy Shear stiffness after yielding K2 Shear displacement at ultimate Am Shear force at ultimate Vm Shear stiffness after ultimate 0 0 Applied axial force Whereas compressive axial force is negative tensile axial force is positive Compressive axial force capacity Axial capacity based on ACI 318 should be negative 119 ZeusNL User Manual hsv Hysteretic shear model under axial force variation Parameters required for the above ZeusNL curve type is described as below from left column to right column 1 The first column represents the level of axial force of interest zero axial force level three levels of compressive axial force and two levels of tensile axial force which can be defined by user Say for instance if you choose 10 20 and 30 of axial Capacity in compression and 10 and 30 of axial capacity in tension you can define parameters in the first column as 0 0 0 1 0 2 0 3 0 1 and 0 3 from top to bottom Hence level of axial force of interest can freely be defined by user 2 The first row of the second column is an identifier of each hysteretic curve The curve number stands for a numbering in sequence in order to trace each hysteretic curve assig
47. ation e Selecting material number 1 Steel is the best solution when monitoring curvature because it gives more stable results and it is common for all sections Section width has to be the maximum distance between steel bars along the direction of interest for concrete sections and the section width along the direction of interest for steel sections F 3 3 Running the analysis After completing the file and monitor list possibly saving the latter too analysis is ready to run If the program mode is set to Dynamic pushover though one last parameter has to be specified which is the scaling factors Three numbers are needed the Start scaling factor the End scaling factor and the scaling factor Step For Fa 2 instance if numbers 1 0 2 0 and 0 2 are entered respectively six dynamic analyses will run for EACH file specified in the file list with record scaling factors of 1 0 1 2 1 4 1 6 1 8 and 2 0 In order to run only one dynamic analysis for each file Start end End numbers must be the same Step is ignored If Start and End numbers are 1 0 then the dynamic analysis will be the same as if it was run under the ZeusNL core program Two extra options are also available The first one is to show or hide the console window during the analysis and the second one is to keep the bulk output of the analysis NUM files Enabling the second option should be used only if special post processing of the analysis results beyond t
48. can choose the value of the x and y multipliers which are the value with which the actual results are multiplied to derive the curve e g multiply everything with 0 001 to get displacements in m rather than mm The user can choose any value positive negative or even zero for the multipliers After selection the diagram is re plotted with the new multiplier values 3 12 1 2 Table Output facility If the user wants to obtain the model vs time in a table and there are more than 10 nodes the Table Output facility should be used Fig 48 TES File Edit 0 00034 0 00034 0 00068 0 00068 0 00102 0 00102 0 00138 0 00138 0 00174 0 00174 0 00044 0 00179 0 00179 0 00263 0 00219 0 00219 0 00604 0 00357 0 00357 0 00148 0 00534 0 00534 0 02536 0 0026 0 0026 0 07607 0 01422 0 01422 13045 0 05196 0 05198 0 14587 10246 0 10246 0 07269 0 13413 0 13413 0 15084 0 09544 0 09544 0 50553 0 06475 0 06475 0 93606 0 36563 0 36563 1 41115 0 78019 0 78019 1 904 1 25594 1 25594 2 39718 1 74756 1 74756 2 09700 2 25575 2 25505 3 45305 2 71944 2 71944 4 13636 3 23096 3 23096 4 97174 3 85633 3 85633 5 93069 4 64557 4 64557 7 04685 5 66091 5 66091 0 33523 6 92625 6 92625 Fig 48 Table Output facility of the Post Processor 66 ZeusNL User Manual The Table Output facility simply allows the user to obtain the nodal displacements velocities or accelerations the cubic or
49. culated using SRSS or CQC 4 Update increase the load factor The forces applied at each story i are evaluated as the product of the updated load factor the nominal load at that story and Fi 71 ZeusNL User Manual 5 Apply the new calculated forces to the model and calculate the members forces displacements and rotations the interstory drifts the new base shear and top displacement etc at the new equilibrium state Calculate the updated stiffness matrix Kror of the structure Return to step one for the next step of the pushover analysis The procedure is depicted as a flowchart in Fig 42 Note before the pushover procedure starts an eigenvalue analysis is carried out to determine the initial load distribution that is applied at the first step The main advantage of the algorithm is that it permits the application of the exact forces profile derived by the eigenvalue analysis at every step without stability and convergence problems The algorithm is able to accept many different options such as a Neglect any spectral amplification and scale according to the modal properties of the structure only a Scale according to a user defined or code specified spectrum instead of a spectrum derived by a given record a Scale only the increment of forces applied at each step and not the total forces already applied to the structure in previous steps Then add the scaled increment to the already applied forces that remain unc
50. dynamic loads applied at the supports in the x direction will be used Again the user can add remove edit or increment the loads Note for this module the user can add the same load value direction type to more than one nodes at a single step specifying many nodes at the Add Load dialog box use the Ctrl key for multiple selections 19 ZeusNL User Manual 2 1 3 10 Equilibrium Stages This module specifies the stages of time intervals at which structural equilibrium is established In other words the user specifies the time steps at which the forces and displacements of the structure are equilibrated The user can have different stages with different time steps depending on the difficulties in convergence that may arise at different times of the dynamic analysis for more demanding analyses a smaller time step is required This is done by specifying the end time of the stage that should be larger than the end time of the previous step and the number of steps The program calculates the time step value for each stage It is equal to the difference between the end time of the current stage and that of the previous stage divided by the number of steps of the current stage For the first stage the time step is equal to the difference between the end time and the Start Time defined at the Time History Curves module divided by the number of steps 2 1 4 Running the analysis After reviewing the different modules it is time to
51. e Element Connectivity page and clicking the Edit button The user can change the boundary conditions of many nodes by selecting them in the Restraints page and clicking the Edit button a Incrementation The user can easily create new nodes elements and loads incrementing the existing ones This was shown in an example in Section 2 The process is straightforward However it is important to specify the correct increment so that there are no conflicts between the new and the existing items e g creating a new node with the same number as an existing node or applying a load to a node that does not exist a Subdivision If the user selects one or more linear elements and subdivides them the program creates a new node in the middle of them and two new elements of the same element class replace the existing one Note this procedure applies only to linear elements cubic dmass or rdamp Note each material section element class node and element should have a unique identifier word or number or word number that should be in a valid format Valid ZeusNL identifiers should be up to eight characters long Moreover they should not contain spaces or the characters or amp If the user pastes one of the tables where an item with an identifier already exists ZeusNL adds a star at the end of it so that the new name is unique 3 3 Materials A selection of four material types is available in ZeusNL libraries Based on
52. e Name should be LARGER than zero and in ASCENDING order 3 cancel fervi a T Load Factor 4 ee et ee 4 MO SO oe or oe ee Load F actor I I L I I r I L I Fig 25 New user define curve The applied loads can be defined in the Applied Loading module as an initial load and a static time history load Fig 26 The process is straightforward Note the vertical is applied downwards and therefore should be negative and that in order to apply double or triple the variable horizontal load the user would only have to change its Value parameter from 1 0 to 2 0 or 3 0 respectively t Classes Nodes Element Connectivity Restraints Time History Curves Applied Loading Equilibrium Stages Node Number Initial Load 11 y Force 1500 Static Time History Load 11 x displacement 1 crv Fig 26 Applied loading Finally the equilibrium stages need to be defined One stage for the 16sec of pseudo time of our test will be defined with 320 steps The time step is 0 05 sec The model is ready to run Click Run gt Run and wait for the analysis to finish After the termination the hysteretic curve for the wall needs to be plotted Run the Post Processor Tools gt Post Processor and open the project s num file Choose to plot the x displacement of node 11 for the x graph axis and the support moment M of node 1 for the y axis Click the View Curve button to view the resulting hysteretic cur
53. ed called sbeam for the beams rcts type For this example the program assumes that all the columns beams have identical sections If the user edits one of the sections for example sbeam again with the Edit button or by double clicking a Section Properties dialog box will appear which is similar to Fig 5 In this dialog box the section s name type materials dimensions and reinforcement may be modified Depending on the selected section type different numbers of materials one for steel sections three to four for RC and composite sections and dimensions one to nine are specified The materials available are those defined in the Materials module reinf conf and unc The program has selected reinf for the reinforcement conf for the confined region and unc for the unconfined region There is a description of the dimensions needed but also notice that whenever the user focuses on a dimension textbox a red line is drawn on the sample section picture that explicitly shows the edited dimension For RC sections the area and the location of the reinforcing bars has to be defined Adding removing and editing bars is easy with the corresponding buttons and is done in the same way materials were added edited and removed Note all the bars have to be within the confined concrete region Moreover since the sections are symmetrical only the bars of the positive 1 3 quadrant have to be specified for the rectangular section and onl
54. ef Where GF out of balance forces G out of balance moments Fre reference force defined in Settings gt Convergence criteria Mret reference moment defined in Settings gt Convergence criteria n number of translational freedoms n number of rotational freedoms The second criterion which is the default is based on the maximum iterative increment of displacements which requires the definition of displacement and rotation reference values n n P P ref i d ref max 9 lt tolerance gt convergence i i Where d iterative displacement 58 ZeusNL User Manual dp iterative rotation i dret reference displacement defined in Settings gt Convergence criteria Pref reference rotation defined in Settings gt Convergence criteria n number of translational freedoms n number of rotational freedoms 3 10 6 Output The output settings determine a Output Frequency Specifies the numerical data to be output o When frequency 0 output is printed at all the equilibrated steps including the step reduction o When frequency 1 output is printed at all the equilibrated steps without step reduction levels o When frequency n output is printed every n equilibrated steps a Stress Strain Output Specifies whether the stresses of all the monitoring points of the two Gauss points of each element are printed to the output file Use this functi
55. efault The Program Defaults button restores the default program settings Save Settings Another option is to keep the current settings for the next run each time the user closes the program Check the Save Settings checkbox Tab Position Determines the position of the tabs in the main window Multiple Tabs Determines whether the tabs appear on single or multiple rows when there is lack of space Autosave ZeusNL saves a backup of the input file at regular intervals the default is 5min The backup files have a bak extension If a zero value is specified no backup is kept 3 10 2 Template When four element members are selected from the template the user may want to specify the exact length of these elements The default is that the member is divided in elements of length 15 35 35 15 Changing the option for the end element of the member allows for changing these percentages 3 10 3 Integration scheme These settings are useful only for dynamic analysis and allow for the determination of the integration algorithm and their parameters alpha beta and gamma for HHT beta and gamma for Newmark Two algorithms are available Newmark default and Hilber Hughes Taylor Note the default values Newmark beta 0 25 and gamma 0 5 are optimal and the user does not need to change them under normal circumstances 3 10 4 Iterative strategy The settings below determine the iterative strategy employed during the solution pr
56. element class of a large number of elements in one step by making a multiple selection and clicking Edit For example this is very useful when the user wants to the change the beams element of one story from one element class to another 2 1 3 7 Restraints The user can easily specify the restrained nodes by selecting them and clicking the Edit button The entire process is straightforward however please note something very important about restraints 18 ZeusNL User Manual In dynamic analysis the restrained DOF at the supports in the direction of the earthquake must be released That is why the restrained DOF of the supports in the model are y z rxtry rz but not x x is the direction of the earthquake 2 1 3 8 Time history curves This module specifies piecewise linear curves for dynamic or time history analysis One has been created with the template by selecting the record The defined curve will be applied with certain rules to the structure at the next module Applied Loading There is a box at the left of the main window with the Start Time of the analysis This is the time when the analysis starts zero for the model If the user double clicks on the curve the Edit Curve dialog box opens Here the applied curve can be change i e its duration or even the selected file For every curve there is a delay parameter The delay which should always be positive is the time after the start time that the curve is applied
57. ely confined concrete core as well as the effect of tie spacing and confining pressure It is recommended to use for the simplified uniaxial concrete model for square sections with uniformly distributed longitudinal steel Eight parameters are required concrete compressive strength steel compressive strength strain corresponding to maximum stress in plain concrete ratio of the volume of total lateral reinforcement to the volume of core center to center distance of outer tie tie spacing number of longitudinal bars and area of one longitudinal bar frp1 Uniaxial constant fiber reinforced plastic confined concrete model 39 ZeusNL User Manual For a comprehensive description of the material types refer to Appendix A 3 4 Sections Fourteen steel RC and composite section types are available in ZeusNL libraries rss Rectangular solid section css Circular solid section chs Circular hollow section sits Symmetric l or T section alcs Asymmetric L or C section pecs Partially encased composite I section fecs Fully encased composite section rcrs RC rectangular section rccs RC circular section rcts RC T section rcfws RC flexural wall section rchrs RC hollow rectangular section rchcs RC hollow circular section rcjrs RC jacket rectangular section For a complete description of the section types refer to Appendix B Each section is described by a set of sectional dimensions 1 through 9 depending on the section type and
58. erated in the structure due to the displacements However if response control is used controlling the displacement of n3 and applying forces rather then displacements the program applies forces but calculates the load factor of the forces so that the displacement of n3 is equal to the displacement value specified by the response control parameters displacement increment and steps The program actually controls only the n3 displacement and calculates the displacement of n1 and n2 from structural equilibrium Automatic response control refers to a procedure in which a new DOF is automatically chosen by the program for response control whenever convergence difficulties arise during the analysis The chosen node is the one having the highest rate of nominal tangential response 50 ZeusNL User Manual New Loading Phase x Phase Type Automatic Response Control Maximum Displacement Limit 100 Minimum Displacement Limit pe o Mode Name 1351 Direction eoo Fig 35 Automatic response control in ZeusNL The parameters required for this control type define a termination condition for the procedure The procedure terminates if the displacement of the selected node in the selected direction exceed the specified limits Do not confuse the DOF selected by the program for the response control with the DOF specified by the user to define the end condition of the procedure Note automatic control cannot be t
59. ere mass 1 nz 8000 10000 12000 Fig E5 Example of the use of one non structural node in 2D analysis 125 ZeusNL User Manual Appendix The ZBeer Utility Does the idea of running hundreds of dynamic or static pushover analyses by the press of one button sound appealing But what happens with the gigabytes of outcoming results when only a few response parameters are of importance Shouldn t they be automatically filtered calculated and stored ready for plotting If these all sound visionary the ZBeer utility brings them to reality uncovering free time and justifying its name Originally developed under DOS and Linux platforms to interact with the ancestors of ZeusNL ADAPTIC and INDYAS the ZBeer utility has been written from scratch for Windows featuring automatic running of static pushover and dynamic pushover analysis also referred as Incremental Dynamic Analysis IDA for multiple files and various response monitoring parameters F 1 Overview The ZBeer utility is activated by Tools gt ZBeer in the main ZeusNL window or by pressing its associated button in the Run Tools toolbar Figure F1 shows the main window 126 ZeusNL User Manual of ZBeer It is split into three regions the Input region at the top left the Status region at the top right and the Chart region at the bottom Story Shear Drift Story Shear Drift Story Shear Drift Moment Curvature Moment Curvature Moment
60. es Fig 3 The model together with a list of the created nodes Depending on the type of analysis that is running different modules will appear For example in dynamic analysis there is a page called Time History Curves for the description of the loading acceleration curve applied to the supports Apparently this module is not needed in pushover conventional or adaptive or eigenvalue analysis In the same way in pushover analysis there is a page called Loading Phases that is not needed for dynamic analysis For a complete description of the available ZeusNL modules refer to Section 3 Save the project with File gt Save As Note the input data files of ZeusNL should always have the extension dat 10 ZeusNL User Manual 2 1 3 1 Analysis Select the type of analysis dynamic time history static time history conventional pushover adaptive pushover eigenvalue or static with non variable loading 2 1 3 2 Materials In the Materials module the user can specify the different materials available for the current project These materials are then used to define sections at the Sections module Each material has a material type stl0 stl1 stl2 for steel con1 con2 con3 con4 or frp1 for concrete refer to Appendix A for a detailed description of the material types and specific material properties i e strength The Young s modulus strain hardening parameter etc Each material also has a distinct name with which it is
61. es Element Connectivity Restraints Applied Loading Loading Phases Adaptive Parameters General Displacement Limit Condition Frequency fi Node Name The load distribution is updated at every equilibrium step but not at step Jnisi z reduction levels Fie Edit view Define Settings Tools Run Help Ose SR BAR lt aT Als 5 Direction ko dg Minimum Limit Loading Type 0 Total Loadinq The storey shear of the next step is calculated From an entirely new set of forces accounting for the existing load factor and the current state of system response Maximum Limit 360 Modal Combination Type sr55 by The SRSS method is used in modal combination for the evaluation of the updated force distribution Fig 55 Adaptive parameters page 1 I ZeusNL C 4temp tut4_AdapStaticTimeHistAnal dat File Edit View Define Settings Tools Run Help Os DEM SR BME lt gt oo A cas O x static Adaptive Pushover Analysis E fl i Materials Sections Element Classes Nodes Element Connectivity Restraints Applied Loading Loading Phases Adaptive Parameters Options Spectral Amplification Given Record x 0 3523 Response 0 61822 0 88498 1 32444 1 22221 2 i i H view Text File i 1 51185 1 35989 1 19556 1 19621 1 35305 1 22421 0 02 1 24551 1 29762 1 21543 1 26728 1 15008 1 00569 1 02106 1 0437
62. f the first column element col1111 are n111 and n111 y1 They accurately define the geometry of the element but what about its section and its orientation The section is scol defined in the Sections module It s clear that the 2 local axis of the section coincides with the y global axis But what about the other two axes Which global axis x or z coincides with the 1 local axis of the section This is why a third node is required to accurately define the element The element end nodes together with the third node nsn10071 define a plane in the 3D space The section s strong axis i e axis 3 lies on that plane and for the model coincides with the x global axis Like the other modules the user can add remove and edit the selected elements However there is also an Incrementation and a Subdivision facility The automatic incrementation of the elements works more or less in the same way as the incrementation of the nodes However here the increment of the element number together with the increments of the node numbers have to be specified The subdivision can only be applied to linear elements and permits the fast and easy subdivision of each element in two by creating a new node at the middle of it The user may want to subdivide an element in the critical areas of the structure in order to increase the accuracy of the analysis One feature that the user will find very useful is the ability to change the
63. for example 250 monitoring points The model s nodes elements and restraints are depicted in Fig 21 22 and 24 For their derivation it is advisable to use ZeusNL Incrementation facility For example after defining the first element 1 the user can easily derive the other elements as in Fig 23 Also note the non structural node 100 that is used for the definition of elements and that all the nodes are restrained for the out of plane deformations z rxtry 30 ZeusNL User Manual I ZeusNL C 4temp model4 dat i HELLS File Edit View Define Settings Tools Run Help DS amp HE 68 ame lt gt lt aT A aas Static Time History Analysis HCI la Bl 3 Materials Sections Element Classes Nodes Element Connectivity Restraints Time History Curves Applied Loading Equilibrium Stages Node Number x v Z Type 1 D 0 D structural Add 2 0 50 0 structural 3 0 100 D structural Edit 4 0 200 0 structural 5 0 300 D structural 6 0 400 D structural Delete 7 0 500 0 structural 8 0 600 D structural 9 0 800 0 structural Incrementation 10 0 1000 0 structural _Incrementation 11 0 1200 0 structural 100 100 1300 0 non structural Move Plot Options V Structural Nodes J Non Structural Nodes IV Elements IV Joints JV Lumped Masses IV Distributed Masses IV Dashpots J Rayleigh Dampers IV Restraints J Node Names 1200 i000 800 600 400 400
64. for the dynamic analysis is specified The program assumes that the time and acceleration values are given in a text file in table format such as Loma Prieta Earthquake 17 OCT 1989 2 000000E 02 4 000000E 02 6 000000E 02 8 000000E 02 1 000000E 01 1 200000E 01 1 400000E 01 1 600000E 01 1 800000E 01 2 000000E 01 2 200000E 01 2 400000E 01 2 600000E 01 2 800000E 01 3 000000E 01 3 200000E 01 4 5345 76E 04 8 691271E 04 9 069152E 04 7 255322E 03 7 255322E 03 2 569593E 03 8 653483E 03 2 191712E 02 4 394760E 02 4 039552E 02 8 955 788E 03 1 900743E 02 1 549314E 03 2 191712E 03 2 494017E 03 1 012722E 02 ZeusNL User Manual Select Accelerogram x Ok Start Time Cancel Time Column o o Scaling Factor Acceleration Column 9810 View Text File First Line open File Last Line Mote that acceleration values should Update View be in nin sec Acceleration ae ae ae ee ee he ee oe CEEI TEEI Sb bo ee ek eee ee dele eee ee Poe ee ee eee he ee ee ee Fig 2 Template screen two selection of acceleration input The user can specify the columns of the time and acceleration values the first and last lines to be read and the scaling factor The file can be selected with the Select File button whereas if the user wants to view the contents of a specific file the View Text File button opens a text file reader The Update View button simply updates the input data if one of the
65. fuse loads with forces Loads can be either forces or displacements the increment is 3 and the number of steps 100 The total loads applied to the nodes are 15mm 5x3 and 30mm 10x3 respectively These loads will be applied in increments of 0 15mm 15 100 and 0 3mm 30 100 a Response control refers to direct incrementation of the global displacement of one node This displacement is being controlled by the program and at every step is equal to the value displacement increment x number of current steps total number of steps 49 ZeusNL User Manual The parameters that should be specified in this control type are the controlled node the controlled direction the displacement that will be incrementally applied to the node and the number of steps that this displacement will be applied in Fig 34 New Loading Phase xX Phase Type Response Control Displacement Increment mm Cancel fso Steps 100 Node Name 1351 Direction Fig 34 Response control in ZeusNL To clarify assume that there is a very simplified structure with three nodes n1 n2 and n3 O If a load control phase is applied with force loading the program simply increments these forces and calculates the resulting displacements If a load control phase is applied with displacement load the program controls all three displacements of n1 n2 and n3 applies the displacement increments and calculates the forces gen
66. h varies Proportional loads may be forces or prescribed displacements applied at nodes Time history loads Static loads varying according to different load curves in the pseudo time domain The magnitude of a load at any given pseudo time is given by the product of its nominal value which is constant and the variable load factor obtained from its load curve at that pseudo time Time history loads may be forces or prescribed displacements applied at nodes Dynamic loads Dynamic loads varying according to different load curves in the real time domain The product of its constant nominal value and the variable load factor obtained from its load curve at that time gives the magnitude of the load Dynamic loads can be forces or most commonly accelerations applied at the nodes in the global directions Applying initial loads In the Applied Loading module click the Add button to show the Add Loads dialog box Fig 32 More than one node can be specified keeping the Ctrl key down This adds a load of the specified type direction and value to all the selected nodes Initial loads are usually gravity loads applied to the structure before the variable loading Note gravity loads should be applied downwards which means that they should have a negative value 47 ZeusNL User Manual New Applied Load x Initial Load List of Modes nizi xl Cancel Direction Type Value Fig 32 Adding a gravity initial l
67. hanged Depending on the parameters given the algorithm yields slightly different results However the algorithm of Fig 52 inclusion of spectral amplification and total scaling according to a spectrum derived by a record is superior to all the other existing alternatives in terms of accuracy without losing in stability 12 ZeusNL User Manual Carry out Jacobi eigenvalue analysis using the stiffness matrix Kor of the end of the previous step Calculate the new force distribution from the modal properties and the spectral shape new step Apply the new force distribution to the structure Calculate the members forces displacements rotations etc Calculate the new stiffness matrix Ktort Fig 52 Adaptive Pushover algorithm 4 1 2 Running Adaptive Pushover Running adaptive pushover is very similar to running conventional pushover However there are some important differences E The analysis type should be Adaptive Static Pushover rather then Static Pushover The mass distribution of the structure should be modeled for the eigenvalue analysis carried out at each step The proportional loads input is defined in the same way as in the conventional pushover Fig 53 However although it is permitted to use different nominal values for the loads at different nodes it is preferable that the loads have equal nominal values In this way the load applied at every node is determined by the modal characteris
68. hat the support is free to move according to the displacement of the record If the record is corrected there is no problem However if it is not corrected the cumulative displacement may become extremely large In most of the cases the nodal relative deformations are of interest rather than their absolute displacements Fixing the position of the first node eliminates the large absolute displacements of the structure but keeps their relative displacements unaffected to derive a correct shape 3 12 2 2 Create a movie of the analysis ZeusNL allows the user to create a movie of a part of a dynamic static time history or pushover analysis It also allows the user to create a movie with the deformed shapes derived by eigenvalue analysis Open a num file and display the deformed shape at a particular step Change some 3D plot settings such as the colors the background color the axes value the titles etc All these settings are kept in the movie file Select Tools gt Create AVI File First the user will be asked to specify the name of the file AVI type that will be created If the analysis type is eigenvalue the user will be asked for the number of frames per half cycle and the number of cycles Usually the defaults give a good animation result If it is time history or pushover analysis the user will be asked to specify the start and end steps as well as the frequency with which the steps will be read Fig 50 Values up to 3 4 usually
69. he starting phase of a pushover analysis Apart from the above three types of control there is actually a fourth one available only for the adaptive pushover This will be covered in Section 4 There are different possible control schemes that can be efficiently applied a One Load Control phase forces applied and one Automatic Response Control phase Applying forces rather than displacements seems more attractive because force based pushover tends to identify much better structural deficiencies such as soft stories However force based pushover diverges at the peak of the curve and cannot describe the descending branch This is the reason that automatic control is used for the second phase Instead of one load control phase two or more may be used in order to apply the forces in the inelastic range in smaller increments Fig 36 t Classes Nodes Element Connectivity Restraints Applied Loading Loading Phases Type of Control Node Mumber Displacement Limits Load Control 1 100 Automatic Response Control 1351 x 0 100 Fig 36 Load control and Automatic control scheme 51 ZeusNL User Manual a One Load Control phase displacements applied If the user is interested in keeping the ratio of the displacements at the story heights fixed the displacement loading strategy may be used The loading consists of controlled displacement at selected nodes and the ratio of these displacements remains constant during the pushover anal
70. he ZBeer capabilities is intended However keeping the NUM files would result in creating numerous large files and hence the available free disk space should be checked in advance When dynamic pushover is selected the serial number of each run is automatically appended to the NUM filename for consistency 138 ZeusNL User Manual By pressing the analysis will start Let now ZBeer do all the job Depending on the number of analyses scheduled to run the program will finish in seconds minutes hours or even days Closing the console window by pressing its button will interrupt the analysis procedure During the analysis the status window is continually updated showing the current file analyzed the current scaling factor of the record in dynamic pushover and the elapsed times of analysis and collection of results The total running time is finally displayed at the end It is highly recommended not to run any other programs in the background during the analysis procedure in order to prevent possible interference It s better to switch off the monitor and leave the computer alone F 3 4 Getting the results When all the scheduled analyses have been finished results are depicted in the chart window at the bottom of the ZBeer application Actually results are updated during analysis too but the user cannot yet interact with the chart window The chart window always shows the results corresponding to the active data fi
71. he creation of the file list Moreover the SAME monitors that had been used in the past analysis should also be present in the monitors list If both these happen the program environment will be just the same as if the analysis had just finished But beware if the start button is pressed a new analysis will start and all the output files will be reset 143 ZeusNL User Manual F 3 5 The Capacity Curve Discrepancy Factor CCDF Latest studies by the authors of ZeusNL have surfaced the need for defining a measuring quantity for the difference between inelastic static and dynamic analysis in the form of a simple percentage number The Capacity Curve Discrepancy Factor CCDF is a numerically simple but yet efficient way to define the difference between the ordinates forces or moments of a single pushover curve compared to a set of dynamic pushover points both emerging from the analysis of the same structural system Consider the pushover curve S0O S1 S2 S3 S4 and the set of dynamic points D1 D2 D3 D4 D5 of figure F14 Coordinates of each point are given in the parentheses X values stand for displacements or curvatures and Y values for forces or moments as already described earlier Y Values 0 06 60 D4 S3 0 05 50 0 04 45 0 06 45 0 02 40 go 8 s4 0 08 40 e e D1 0 03 40 0 05 40 0 07 40 D5 0 02 30 0 04 30 S1 0 01 20 X Values 0 0 S0 Figure F14 Definition of the Capacity Curve Discrepancy Fac
72. he ten parameters of the astr curve 76 Element Classes Nodes Element Connectivity Restraints Time History Curves 4pplied Loading Equilibrium Stages cubic joint New Element Class Element Class Name i i j ZeusNL User Manual Fig 57 Joint Curve to define a structural gap Element Class Type joint 3D joint element Fx astr hd Fy lin ba Fz lin Y Mx lin My lin Mz lin T Fx Parameters 16010 00500 1801000 50 18010 Fy Parameters fo Fz Parameters fo Mx Parameters fo My Parameters f Mz Parameters x Cancel Add Curve Properties astr i x Initial stifness Ko 10000000000 Displacement do 0 2nd branch stifness K1 ro Displacement di 50 3rd branch stifness K2 ro displacement Initial Stifness Ko 1 10000000000 Displacement do ry 2nd branch stifness Kl Cc ry Displacement di 50 3rd branch stifness kz 10000000000 Cancel T7 Fig 58 Defining a structural gap from ZeusNL graphical environment ZeusNL User Manual 4 3 Background processing 4 3 1 ZeusNL input data files dat It is important to have an idea of what happens beyond the tables and graphics how the input data are saved how they are restored how the program runs etc ZeusNL is based on a text input file to run This file has a dat extension and is also used to save the data The user can
73. hows a completed monitor dialog 134 ZeusNL User Manual By pressing OK the monitor is added in the list and its full description is displayed in the chart window Figure F7 shows an example of the correct definition of this monitor type ban 11411 brn 11412 H brax E at am aut brn edie H brr TE i 2414 c a kb Ol e I h bil e ere Story shears Story 1 col1111 c0l2111 col31171 w ee Story 2 col1211 c0l2211 col321 1 SE i i a Element length 0 45 m Direction Vx Interstory drifts Story 1 Up n321 Down n311 Story 2 Up n331 Down n321 Story 3 Up n341 Down n331 Direction Ux 2211 me Pei 4 brax r EET EN 1000 1000 2000 3000 4000 5000 B000 rjg S000 3000 Figure F7 Definition example of story shear vs interstory drift monitor Enter Monitor F 3 2 3 Element moment vs Section curvature The third and final monitoring option is the element moment versus section curvature figure F8 The curvature is calculated by the formula h where amp and amp are the top and bottom layer strains respectively and h is the height of the section Various strain layers can be selected for each material that constitutes the section but then attention must be paid to the definition of the layer width h After pressing the Add Monitor button a new dialog window appears where the user must select the Moment Curvature monitor type in the top of 135 ZeusNL User Manu
74. ible again in order to enlarge the actual structure The Nodes module contains the standard Add Remove and Edit buttons but there is also an Incrementation button This activates the Nodes Incrementation facility of ZeusNL The user can select one or more nodes and generate new ones in a repetitive manner 15 ZeusNL User Manual Automatic Incrementation x Mode Increment 2 incrementt rom Cancel 1000 Y incrementimm Ao incrementirnm f epetitians Fig 7 Nodes automatic incrementation facility For example select both the n111 and n112 nodes to make multiple selections on the ZeusNL tables click the table items the user wants to be kept holding the Ctrl key down Then with the two nodes selected click the Incrementation button Select a node increment of 10000 This means that the generated nodes will have names n10111 n20111 from n111 and n10112 n20112 from n111 Also select an x increment of 1000 and y and z increments of zero Choose four repetitions this means that for each selected node four new nodes will be generated that makes 8 2x4 new nodes Click Ok and see the new nodes on the 3D plot It should look something like Fig 8 16 ZeusNL User Manual I ZeusNL C temp modeli dat File Edit View Define Settings Tools Run Help OSDA SR BRB lt gt oo 10 x Dynamic Time History Analysis bul CH A w SA aes
75. igenvalue analysis Mass units should be N mm sec2 N 110 ZeusNL User Manual Dmass Cubic distributed mass element Number of nodes 2 Dmass models uniformly distributed mass for dynamic and eigenvalue analysis It uses an updated Lagrangian formulation and a cubic shape function for the transverse displacement and a linear distribution for the axial displacement The mass length units should be in N mm sec2 mm 111 ZeusNL User Manual Ddamp Dashpot concentrated viscous damping element Number of nodes 1 Six three translational and three rotational parameters must be specified Cx Cy Cz Cyx Cy and Cz The elements models nodal viscous damping in dynamic analysis Fz Z Fz Fy V Fy Fyy F XX 112 ZeusNL User Manual Rdamp Rayleigh damping element Number of nodes 3 Rdamp models Rayleigh damping effects in dynamic analysis of space frames Two parameters must be given the proportionality constants al and a2 of mass and stiffness respectively Nodes 1 and 2 define the element connectivity and its local x axis Node 3 is required to define the x y plane and can be a non structural node a1 should be set to zero for dynamic analysis involving ground excitation otherwise damping would be proportional to absolute rather than relative frame velocity All rdamp elements must have the same constant al and a2 to model conventional Rayleigh damping 113 Zeu
76. ill be added to the desktop and to the Start Menu under Programs gt ZeusNL 1 Program Features ZeusNL represents a revolution in Finite Element packages Quite simply there are not many FE tools that put as much power into the user s hands as easily as ZeusNL Some of the many features of ZeusNL Q OD O O DO Completely visual interface No input or configuration files or programming scripts Full control over adding modifying and deleting material models section types nodes elements restraints and loads Six different types of analysis dynamic and static time history conventional and adaptive pushover eigenvalue and static with non variable loading The program accounts for both material and geometrical nonlinearities Accurate and thoroughly tested concrete and steel material models A large variety of RC steel and composite sections The spread of inelasticity along member length and across section depth is explicitly modeled in ZeusNL allowing for accurate estimation of damage accumulation This feature sets ZeusNL apart from most of the similar tools that use lamped inelasticity to model the members non linear behavior High stability and accuracy at very high strain levels enabling precise determination of the collapse load of structures The applied loading may consist of constant or variable forces displacements and accelerations at the nodes The variable loads can vary proportionally or independentl
77. ined region Confined region Number of dimensions 8 Slab thickness Beam height Confined height in slab Confined height in beam Slab effective width Beam width Confined width in slab Confined width in beam 102 ZeusNL User Manual rcfws RC flexural wall section Number of materials 4 Reinforcement Unconfined region Partially confined region Fully confined region Number of dimensions 5 Wall width Confined width Wall thickness Confined area thickness Height of fully confined region 103 ZeusNL User Manual rchrs RC hollow rectangular section Number of materials 3 Reinforcement Unconfined region Confined region Number of dimensions 8 External section height External stirrup height Internal Stirrup height Internal section height External section width External stirrup width Internal stirrup width Internal section width 104 ZeusNL User Manual rchcs Reinforced concrete hollow circular section Number of materials 3 Reinforcement Unconfined region Confined region Number of dimensions 4 External section diameter External stirrup diameter Internal stirrup diameter Internal section diameter 105 ZeusNL User Manual rcjrs Reinforce concrete jacket rectangular section Number of materials 4 Reinforcement Unconfined region Partially confined region Fully confined region Number of dimensions 6 Section height External stirrup heigh
78. ing the element classes the user needs to address the mesh configuration of the model In the Nodes module apart from a list of the nodes there is a 3D plot of the structure allowing for the better visualization and understanding of the model Most of the nodes are structural although there are some non structural ones The question arises What is the difference between a structural and a non structural node For some element types cubic joint dmass and rdamp extra nodes apart from the end nodes should be specified The extra nodes define the orientation of the local axes of the elements In particular cubic dmass and rdamp require a third node to define the local 1 axis and joint requires a third and fourth node to define the 2 and 1 local axes For a comprehensive explanation of the use of non structural nodes as extra nodes for the definition of elements refer to Appendix E By default the non structural nodes are not visible on the plot To make them visible simply check non structural nodes plot option in the Nodes module Alternatively select Settings gt 3D Plot Settings This opens the dialog box from which the user can change the display settings of the 3D plot of the model Go to the Non Structural Nodes tab and click on the Visible checkbox as in Fig 6 The non structural nodes appear in pink all around the model 14 ZeusNL User Manual 3D Plot Options Joint Elements Lumped Mass Dashpot Elements Distrib
79. ions x Bay Length Ratios Storey Height Ratios Frame Distance Ratios Ist bay 1 8 end bay 0 85 3rd bay 1 0 4th bay 1 0 Sth bay 1 0 bth bay 1 0 Fth bay 1 0 eth bay 1 0 ist storey 1 0 ito 1 0 end storey 1 0 2to3 71 0 ard storey 1 0 Sto4 1 0 4th storey 1 0 4toS 1 0 Sth storey 1 0 Stog 1 0 6th storey 1 0 Gtoy 1 0 7th storey 1 0 7tog 1 0 Sth storey 1 0 Stog 1 0 AE Sth bay 1 0 ath storey 1 0 AE E Reference Dimensions Bay Length mm tono Storey Height mm z000 Distance between Frames mm eooo FUE EL LE ELLE LE ELLLER Ok i FREE EER Cancel Fig 44 Template Determination of the dimensions of irregular models 62 ZeusNL User Manual Fig 45 An irregular model created with the template 3 11 2 Data Entry table ZeusNL offers a fully functional graphical user interface that permits fast and easy entry of the required parameters However there may be some experienced ZeusNL users that know the tables format and prefer to add entries directly on a table For these users there is the Data Entry Table facility Tools gt Open Data Entry Table Opening the Data Entry table will open a table with cells that can be edited The columns and the headings of the table are similar to the table of the currently active module For example if the users open the table for the Nodes module i
80. j k formula Q Analysis and Loading Type O Eigenvalue The model is derived ready for eigenvalue analysis Masses are added at the beam column connections No loading is applied Static analysis with non variable loads No masses are added just the initial load in applied Static pushover analysis The user chooses between uniform or triangular proportional loading and is asked to specify the nominal value of the proportional load at the top nodes of the structure Initial gravity loads are also applied No masses are added Two phases are created one of load control and the second of automatic response control The proportional loads are applied in the x direction Adaptive static pushover analysis Although it is a static analysis the mass distribution is required for the eigenvalue analysis As a result masses are added Two phases are created one of adaptive load 61 ZeusNL User Manual control and the second of automatic response control The proportional loads are applied in the x direction o Static time history analysis The user chooses between applied displacements or forces and inputs the loading curve No masses are required The load is applied in the x direction o Dynamic time history analysis The user is asked for an earthquake input accelerogram The accelerogram is applied to the supports on the x direction The x DOF of the supports is released restraints y z rx ry rz Ratios to Reference Dimens
81. lange width Bottom flange thickness Top flange width Top flange thickness Web height Web thickness Bottom flange eccentricity Top flange eccentricity 97 ZeusNL User Manual pecs Partially encased composite I section Number of materials 4 l section Unconfined region Partially confined region Fully confined region Number of dimensions 6 Flange width Flange thickness Web height Web thickness Unconfined concrete thickness Max thickness of partially confined concrete C d P F I E i r H i i i 4 i i 98 ZeusNL User Manual fecs Fully encased composite I section Number of materials 4 l section Unconfined region Partially confined region Fully confined region Number of dimensions 9 Flange width Flange thickness Web height Web thickness Max thickness of partially confined concrete Stirrup width Section width Stirrup height Section height 99 ZeusNL User Manual Crs RC rectangular section Number of materials 3 Reinforcement Unconfined region Confined region Number of dimensions 4 Section height Stirrup height Section width Stirrup width 100 ZeusNL User Manual rCCS RC circular section Number of materials 3 Reinforcement Unconfined region Confined region Number of dimensions 2 Section diameter Stirrup diameter 101 ZeusNL User Manual rcts RC T section Number of materials 3 Reinforcement Unconf
82. last action to return to the previous state otherwise the program will not run with some nodes unconnected to the structure There are some 3D plot options on the left of the screen These are the options most frequently used There is also a Reset button that returns the plot to the default state 17 ZeusNL User Manual and an Animate checkbox that enables the user to see the model from different perspectives The user can also rotate the model if the plot is dragged with the mouse One very interesting feature is the ability to sort the nodes by their number or their x y or z coordinates The user has to click on the header of the node number or the coordinate columns x y or z to sort them in an ascending way If the clicked again the node will be sorted in a descending way 2 1 3 6 Element Connectivity The different elements of the structure are defined here Each element belongs to a specific element class and depending on its element type may have one lImass ddamp three cubic dmass rdamp or four nodes joint The model has only cubic structural elements and Imass mass elements A complete description of all the element types of ZeusNL libraries can be found in Appendix C As mentioned in the previous section the cubic elements are defined apart from their two end nodes with a third node that can be structural or non structural A more comprehensive explanation can be found in Appendix E For example the end nodes o
83. le and the active monitor The term active refers to the currently selected data file in the file list and the currently selected monitor in the monitor list figure F9 By left clicking into these two lists the chart window is updated and the new set of results is displayed figures F10 and F11 for dynamic and static pushover respectively ace Dale bile itor 1 Base Shear Drift i Story Shear Drift Dynamica dat i Story Shear Drift Dynamict dat i Story Shear Drift Dynamics dat i tr Moment Curvature Moment Curvature Moment Curvature Active Monitor Moment curvature Monitor 13 Moment Curvature Figure F9 Active data file and active monitor 139 ZeusNL User Manual Zooming in the chart window can be activated by left clicking and dragging the mouse down rightwards N The opposite move up leftwards N will reset any previous zoom Panning can be activated by clicking and dragging the mouse wheel Left clicking will activate a popup menu which will be described later on Dynamic Pushover File Dynamic2 dat Monitor 8 Moment My 1 col1211 Curvature Material 1 PAAT i aia oe a E XZ D E 5 d D E m 0 0 002 0 004 0 006 0 008 0 01 0 012 0 014 0 016 0 018 0 02 0 022 0 024 0 026 0 028 0 03 0 032 0 034 7 Corresponding p steps Curvature radim No Marks Moments Curvatures Scaling Factors Figure F10 Dynamic Pushover results
84. lement is used in space frame analysis to model pin joints inclined supports elasto plastic joint behavior soil structure interaction and structural gaps through employing appropriate joint curves For the complete definition of joint four nodes are required Nodes 1 and 2 are the end nodes of the element and must be initially coincident Node 3 is only used to define the x axis of the joint and can be either a structural or a non structural node Node 4 is required to define together with the already defined x axis the x y plane and can be a non structural node After deformation the orientation of the joint x axis is determined by its initial orientation and the global rotations of node 1 The force displacement characteristics for the axial Fx the shear forces F and F and the moments M M and M are determined by curves included in ZeusNL libraries lin smtr astr The input parameters are a list of parameters required for the definition of the curves and should be given in the following order F Fy Fz Mx My Mz Element has a Zero initial length since nodes 1 and 2 are coincident The joint element cannot be used to model coupled axial shear and moment actions 2 n4 Ref 2 Z Q gt 7 lies in x y plane n3 Ref 1 ni a after deformation initia lly X 109 ZeusNL User Manual Lmass Lumped concentrated mass element Number of nodes 1 Lmass models lumped masses It is used in dynamic and e
85. lows the previous loading path The user will never need to use the path so there is no need to pay any attention to it The Conditions module specifies the stopping condition of the automatic control phase Simply what is specified in the Loading Phases module of the graphical environment is divided into the two modules conditions and phases Finally the automatic control type is always nod control translation meaning control of the translation rather than rotation of the node defined in condition cnd1 78 ZeusNL User Manual ieo SNE aS gn RT sR gE a a Fe ee Er E re Ed Conditions a a a a ae a ee conditions response cnd name nod name direction Limits enal ALS X O 600 a E E a EEE i a a ga i a a a E E E Phases a ee a a Se ae a ah ae a ee ee ae DE phases load control increment path steps 1 keep 100 automat rc Conero type path cnd name Hod Control translation continue epal Note The user will never have to use them in any way and the user will never be asked to edit the dat file directly 4 3 2 What happens when a project is running After a model has been created and saved that is the dat file when it is run two MS DOS windows will appear one after the other Although only one application is running in reality two different programs called by the graphical environment are running The first reads the data arranges them in a certain way understood by the second and makes some initial calculations
86. lysis are a There are no masses Masses are not needed since there are no inertia forces in static pushover analysis Fig 15 The x DOF is restrained at the supports Fig 15 The Time history Curves and Equilibrium Stages modules are missing There is an extra module instead called Loading Phases This module defines the control phases used to trace the load deflection curve for proportional loading Three types of control are available O Load control refers to the situation where the load factor A is directly incremented and the global structure displacements are determined at each load factor level The applied load can be either forces or displacements Response control refers to the situation where the response displacement rotation of a node specified by the user is incrementally increased The loading applied and the deformations of the other nodes are determined by the solution of the program Automatic response control refers to a procedure in which a new DOF is automatically chosen for response control whenever convergence difficulties arise during the analysis The chosen node is the one having the highest rate of nominal tangential response 26 ZeusNL User Manual There are different possible schemes that can be applied For the time being the default created by the template will be used one load control phase and one automatic response control phase For a complete description of the module refer to Section 3
87. n indicated by the minus sign Three different types of response monitors are available These are 1 Base shear Drift monitor 2 Story shear Drift monitor 3 Element moment Section curvature monitor Enter Monitor These three types are explained in the subsequent paragraphs F 3 2 1 Base shear vs Drift The first monitoring option is the base shear V versus drift d figure F4 Horizontal forces V from support nodes are added and plotted against the displacement or rotation difference between two nodes usually between a top story node and one at the base of the structure global drift Note here that whereas a base node is fixed for static pushover analysis it is displaced and or 131 ZeusNL User Manual rotated during dynamic analysis After pressing the Add Monitor button a new dialog window appears where the user must select the Base Shear Drift monitor type in the top of the dialog window Vex V Figure F4 Base shear versus global drift monitoring Next the base shear has to be defined by Fruen adding all base nodes in a list This is done by entering each node name in the Name editbox and pressing the Add node button Accidentally entered nodes can be removed by pressing the Delete node button Finally the base shear direction must be specified for 2D structures the direction is always Vx whereas for 3D structures i
88. n the user actually wants to see how the structure looks like at 6 02sec when the largest top displacement of node n151 occurs Is there an easy way to identify soft stories What will the second eigenmode of the structure would look like The Deformed Shape Viewer answers these questions Close the Post Processor this takes the user to the Main Program window and open Tools gt Deformed Shape Viewer From the shape viewer open the num file that has been created with the analysis After the file has been loaded a list of the time steps of the analysis appears on screen Select time step 6 68 sec and click the View Shape button In a couple of seconds the deformed shape appears and it is ready to be copied or printed I ZeusNL Deformed Shape iewer Ioj x File Edit Tools Help a SA AMR sas Time 8 12 sec MV 3D View W Aes Ca Joints J Structural Modes fy Lumped Masses J Elements J Dashpots Reset Click list to view deformed shape Output Mo 950 Time Output Wo 951 Time 8 072 Qutput Wo 952 Time 8 076 Output Wo 953 Time 8 08 Output Wo 954 Time 8 084 Output Wo 955 Time 8 088 Output No 956 Time 8 092 Output No 957 Time 8 096 Output No 958 Time 8 1 Output Wo 959 Time 8 12 Output Mo 960 Time 8 14 Output No 961 Time 8 16 Output Mo 962 Time 8 18 Output Mo 963 Time 5 1805 Output Mo 964 Time 5 1616 Output Wo 965 Time 8 1824
89. nd n111 respectively vs time Run the Post Processor with Tool gt Post Processor and open the project num file Select from the drop down lists on the top left of the window Time for the x axis and Interstory Drift for the y axis On the dialog box that opens choose the nodes n151 and n111 select the appropriate direction U that is the direction of the earthquake and click Ok In many cases the user will have to find an item e g a node in a drop down list with hundreds of items If the name of the item node is known start typing it when the drop down list is highlighted and ZeusNL will locate it Click on the View Curve button and the plot is created The values of the plot are shown on the table at the bottom left corner 21 ZeusNL User Manual 5 x I ZeusNL Post Processor C 4temp modeli num File Edit View Tools Help Ais Time x multiplier 1 y AxiS Interstorey drift Nodes 1151 and 1111 x direction v multiplier 1 View Curve 0 00356 Interstorey drit eTA REIER 0 06 0 00964 0 06 0 00504 O 1 0 02189 O12 0 073 0 i4 0 12537 0 16 0 14796 0 18 07043 2 0 16344 O22 0 5466 0 24 1 02577 0 26 1 56698 Fig 10 ZeusNL Post Processor To convert the displacement values from mm to cm multiply all of the y values of the plot by 0 1 Select Tools gt Settings and change the y multiplier to 0 1 The diagram is then re plotted with all
90. nditions Supports and joints Q Cubic Cubic elasto plastic 3D beam column element It is used for detailed inelastic modeling making use of the uniaxial inelastic material models described above It accounts for the spread of inelasticity along the member length and across the section depth Joint 3D joint element with uncoupled axial shear and moment actions Lmass Lumped concentrated mass element used in dynamic and eigenvalue analysis Dmass Cubic distributed mass element Ddamp Dashpot concentrated viscous damping element used in dynamic analysis Rdamp Element that models Rayleigh damping for dynamic analysis 13 ZeusNL User Manual These element types are used to define element classes An element class is a group of properties referring to a particular element category The element types different types of elements available in the ZeusNL libraries should not be confused with the element classes In each ZeusNL project there may be many different element classes of the same element type For example in the model there are two element classes col and beam of the cubic element type and three element classes of the Imass element type mass1 mass2 mass4 The element classes defined here are used in the Element Connectivity module to define the connectivity of the elements in the mesh configuration A complete description of the element types of ZeusNL is found in Appendix C 2 1 3 5 Nodes After defin
91. ned to each direction of a member For example if a bridge structure has three piers user has to define six curves three in longitudinal and three in transverse direction In this case user can define the curve number as 1 to 6 corresponding to each direction of each pier The second and the third row of the second column represent the axial force capacity in compression and in tension respectively these values should be positive 3 The third column represents shear displacement at cracking corresponding to each level of axial force defined in the first column 4 The fourth column represents shear displacement at yielding corresponding to each level of axial force defined in the first column 5 The fifth column represents shear displacement at ultimate corresponding to each level of axial force defined in the first column 6 The sixth column represents shear force at crack corresponding to each level of axial force defined in the first column 7 The seventh column represents shear force at yielding corresponding to each level of axial force defined in the first column 8 The eighth column represents shear force at ultimate corresponding to each level of axial force defined in the first column For the parameters of the curve type hsv monotonic shear force shear displacement curve subjected to each level of axial force defined has to be evaluated in advance 120 ZeusNL User Manual hfc Hysteretic flexure m
92. not all the 2500 lines of the accelerogram simply click the Update View button for the changes to take effect Fig 40 54 ZeusNL User Manual New Curve from File i X Curve Hame ervi Start Time Cancel Open File wiew Text File Update view Time Column Acceleration Column First Line Last Line Time Value gt Value 0 36 0 030 Time Fig 40 The New Curve from File dialog box There is also a Delay parameter which is the time in seconds after the Start Time that the curve starts being applied At first this does not seem to have a purpose For the majority of cases it is not needed and should be kept to zero However it can be used efficiently to run dynamic analysis with asynchronous earthquake loading by defining curves that are exactly the same but have different delay parameters Fig 41 t Classes Nodes Element Connectivity Restraints Time History Curves Applied Loading Equilibrium Stages Curve Name Curve Type Delay File Values From File 0 0 Examples LomaPrieta txt 1 2 1 500 From File 0 12 Examples LomaPrieta txt 1 2 1 500 From File Examples LoamaPrieta txt 1 2 1 Examples LomaPrieta tet 1 2 From File Fig 41 Curves for asynchronous earthquake input Adding the dynamic loads in the Applied Loading module is very similar to adding Static time history loads Fig 42 The user has to specify the node s the direction the
93. o plastic 3D beam column element Number of nodes 3 The cubic elasto plastic element can adequately model members of space frames with geometrical and material nonlinearities For the evaluation of the element forces numerical integration is performed at the two Gauss points For this purpose the section at each Gauss point is divided into a number of monitoring points monitoring areas the stress strain relations of which are considered during the integration For single material sections sits rss 100 monitoring points are usually enough For more complicated sections fecs rcts rcfws this number should be increased to about 200 or more For accurate inelastic modeling it is advisable to use more than one cubic element per member Nodes 1 and 2 are the end nodes of the element The element local x axis lies on the line defined by them Node 3 is required to define the local x y plane and can be a non structural node It is possible and advisable to use one non structural as the third node for all the cubic elements that lie on the same plane of the model 1 1 2 2 3 7 7 M32 i N lt lt oe gt gt gt M N Fo OM M71 2 x 1 y gt 3 1 n2 gt 3 z 1 ref i 2 lt es Sg gt gt Mo A Fo M SE 1 SS 3 ye n1 108 ZeusNL User Manual Joint 3D joint element with uncoupled axial shear and moment actions Number of nodes 4 The joint e
94. oad at many nodes of the model 3 9 2 Applying loads for pushover analysis In pushover analysis the applied loading usually consists of initial constant gravity loads in the y direction and proportional loads forces or displacements in the x direction The procedure for adding proportional loads is similar to the procedure for adding initial loads Fig 33 48 ZeusNL User Manual New Applied Load x Proportional Load 7 Cancel List of Nodes Direction Type Value Fig 33 Adding proportional loads at different nodes This process indicates the nominal values of the proportional loads After doing so however the user should specify some kind of rules to define how these loads will be increased in how many steps etc This is done in the Loading Phases module This module defines the control phases used to trace the load deflection curve for proportional loading Three types of control are available a Load control is where the load factor A is directly incremented and the global structural displacements are determined at each load factor level For the load control phases only an increment value the factor by which all nominal loads are multiplied to get the target loads and the number of steps in which this target load is applied are required Loads can be either forces or displacements For example assume that the nominal proportional loads applied to two nodes are 5mm and 10mm Note do not con
95. ocedure E Number of Iterations Specifies the maximum number of iterations to be performed at each increment Number of Initial reformations Specifies the number of initial reformations of the tangent stiffness matrix to be performed at each increment 57 ZeusNL User Manual a Step Reduction Specifies the step reduction factor when convergence is not achieved When the solution diverges or fails to converge within the maximum specified iterations the increment is reduced by the step reduction factor The increment can be reduced for up to three times resulting in an increment step reduction smaller than the original value a Divergence Iteration The iteration at which divergence checks are performed a Divergence Criterion The reference value used to check for divergence of the solution The Newton Raphson strategy is employed by using a number of initial reformations equal to the number of iterations Using a number of initial reformations equal to zero is equivalent to the modified Newton Raphson strategy 3 10 5 Convergence criteria The settings determine the convergence criteria for the iterative procedures There are two different convergence criteria in ZeusNL The first is based on the norm of the out of balance forces Convergence is attained when the norm is smaller than the tolerance defined in Settings Gf G n n gt DE lt tolerance gt convergence i F i l M ref r
96. odel under constant axial force Shear force lt 5 F RD HUSE Shear deformation or Flexural deformation i l I Initial flexural stiffness Ko Flexural displacement at cracking Aer Shear force at cracking Ver Flexural stiffness after cracking K4 Flexural displacement at yielding Ay Shear force at yielding Vy Flexural stiffness after yielding K2 Flexural displacement at ultimate Am Shear force at ultimate Vm Flexural stiffness after ultimate 0 0 121 hfv ZeusNL User Manual Hysteretic flexure model under axial force variation Parameters required for the above ZeusNL curve type is described as below from left column to right column 1 The first column represents the level of axial force of interest zero axial force level three levels of compressive axial force and two levels of tensile axial force which can be defined by user Say for instance if you choose 10 20 and 30 of axial Capacity in compression and 10 and 30 of axial capacity in tension you can define parameters in the first column as 0 0 0 1 0 2 0 3 0 1 and 0 3 from top to bottom Hence level of axial force of interest can freely be defined by user The first row of the second column is an identifier of each hysteretic curve The curve number stands for a numbering in sequence in order to trace each hysteretic curve assigned to each direction of a member For example if a bridge structure has three piers user has to
97. on only when absolutely necessary It may result in huge output files hundreds of Mb for very large structures 3 10 7 Eigenvalue These settings specify the number of required eigenvalues the range of natural frequencies of interest and other parameters E Q Number of Eigenvalues The number of required eigenvalues Maximum Number of Steps The maximum number of steps required to converge to the solution Minimum Natural Frequency of Interest and Maximum Natural Frequency of Interest The default values zero and extremely large value mean that all the natural frequencies are of interest Frequency Shift during the solution of the eigenproblem There is no reason to change the default zero The algorithm does not necessarily output the eigenmodes in an ascending or descending order 59 ZeusNL User Manual 3 11 Other facilities 3 11 1 Template Open Template x Reference Dimensions Bay Length imm 5000 Storey Height imm 3000 Distance between Frames 6000 Number of Bays fe E Number of Storews fa Number of Frames Z Structural Model Structural Type Reinforced Concrete Structure Elements per Member Node Naming Convention Int 11 x1 Loading Analysis Type Eigenvalue Analysis Fig 43 Template screen There are many options that the user can choose from a Define the geometry of the structure 3D or 2D number of bays stories
98. or 1 32829 118 Load Factor Fig 17 The deformed shape at the last step of the pushover procedure 28 ZeusNL User Manual 2 4 Tutorial 4 Static Time History Analysis Static time history analysis is usually used for the simulation of experimental tests on specimens For example the user can model an imaginary cyclic test on an RC wall Assume that the loading consists of a constant axial compressive force and a variable displacement applied on the top of the wall Fig 18 according to a pre defined pattern constant axial load b 20 predefined 15 displacement pattern i displacement pattern 20 Fig 18 Cyclic test on an RC wall This time a template will not be used The model will be created from scratch module by module Even without the Template facility creating a model with ZeusNL is simple 2 4 1 Structural Configuration From the Analysis module select Static Time History analysis In the Materials module the user will have to define four materials for the project one for the reinforcing bars and three for concrete since the RC wall section rcfws consists of four different materials see detailed description in Appendix B Use the stl1 material type for the steel material long rei and the con2 type for the three concrete materials unconfined conc1 partially confined conc2 fully confined conc3 Note the parameters of conc1 conc2 and conc3 a
99. orials as it will get the user up and running in the quickest time possible 1 3 Conventions There are a number of terms and conventions used in this manual that the user should become familiar with a Menu commands For example Menu Name gt Command Name such as File gt Save means open the File menu and click the Save command a Model The model of the structure that is created with ZeusNL It includes the complete description of the structure from the materials and sections types to the nodes elements and restraints a Windows This refers to the Microsoft Windows product line that is Windows 95 98 Windows Me Windows NT Windows 2000 and Windows XP Note that the program is not supported by Windows 3 1 systems ZeusNL User Manual a Project This refers collectively to the files and options that are used in ZeusNL for a particular analysis ZeusNL input data files are saved and loaded with the extension dat However there are other files created during the formation of the model e g the input curve files crv that are files that describe the loading of the modeled structure A complete description of all the files created by ZeusNL will be given in Section 4 a Dialog boxes These are the windows that open for data input The user either enters the required data and clicks OK to accept the entries or clicks Cancel to cancel the operation a Pop up menus The shortcut menus that appear when
100. ote in order to run 2D analysis all the nodes should have z 0 and should be restrained in the z rx try directions For these models z 0 and z rxtry restrained for all of the nodes the z rxtry restraints are not shown on the 3D plot for reasons of clarity Also note In dynamic analysis the restrained DOF at the supports in the direction s of the earthquake must be released When changing analysis type to and from dynamic analysis ZeusNL will remind the user to change the boundary conditions at the supports 46 ZeusNL User Manual 3 9 Applied Loading Depending on the selected analysis type different load may be applied to the structure Q Eigenvalue analysis No loads are applied The stiffness and mass distribution of the structure are needed Static analysis with non variable loading Only initial loads are allowed Static pushover analysis conventional and adaptive Initial and proportional loads may be applied Static time history analysis Initial and static time history loads Dynamic time history analysis Initial and dynamic loads Definition of load types Q 3 9 1 Initial loads Static loads that are applied prior to any variable load They can be forces or prescribed displacements applied at nodes Proportional loads Static loads that have proportional variation The magnitude of a load at any step is given by the product of its nominal value which is constant and the current load factor whic
101. other words comparing static to dynamic not the opposite The calculation of PP was implemented as an extra utility in ZBeer This utility is activated by pressing the PP button in the right of the open data file button The new dialog requests the output files FPT TIA psh of the static and dynamic pushover analysis to be entered in the corresponding edit boxes The monitor numbers to be compared can be changed by clicking the up down buttons The locking checkbox on the right makes the two monitor numbers for static and dynamic pushover analysis to be the same which is mostly the case Moreover the user can select to compare either the response maxima or the maximum versus corresponding values with or without a time step window Finally by pressing the Compare button the PP value is automatically calculated and displayed for the current monitor number and dynamic pushover scheme 145 ZeusNL User Manual F 3 6 Case study After the installation of ZeusNL a special directory under the name ZBeer Examples is created inside the installation directory usually C Program Files ZeusNL Inside this directory there are five dynamic and five pushover analysis data files already prepared featuring the same three story two bay concrete structure with variable concrete strength as follows Static1 dat Dynamic1 dat Concrete C12 Static2 dat Dynamic2 dat Concrete C20 Static3 dat Dynamic3 dat
102. parameters i e the last line has been changed There are a couple of important things to note a Time values should be in ascending order and larger than zero Values less or equal to zero are simply neglected by the reader Moreover non numerical input is not accepted a If the given acceleration values are in g then a scaling factor of 9810 is required to change the units to mm sec The accelerogram by default will be applied in the x direction a By right clicking on the table or the graph a very useful pop up menu appears The user can copy or print the selected time and acceleration values and the graph to other applications word processing e g Microsoft Word or spreadsheet e g Microsoft Excel Furthermore the user can change numerous options of the graph line color or thickness background axes values etc before actually copying or printing In ZeusNL almost every table or chart has a pop up menu ZeusNL User Manual After selecting the input accelerogram click the Ok button A 3D structural model of a four story building which consists of more than 100 elements has been created The static gravity loads and the dynamic earthquake loading have also been applied 2 1 3 Program modules Apart from the menu and the toolbars with the buttons that are normally found on any application for the Windows operating system in ZeusNL there is a series of pages modules On every page different input
103. re created the first with scaling or load factors depending on the type of analysis the second with X values displacements curvatures and the third with Y values forces moments In dynamic pushover analysis the Copy Values option is tripled absolute maxima maximum X versus corresponding Y and the opposite with the latter two referring to the currently specified time step window e Open Output File in Excel The last export option is to open the Output File in Microsoft Excel The output file is automatically created for EACH file included in the file list under the same directory the same file name and the psh extension Each output file contains results for all the monitors included in the monitor list It is tab delimited and can be easily dragged and dropped in Microsoft Excel for further processing like creating comparative plots from different analyses By selecting this menu option the output file of the currently active file which is currently selected in the file list is automatically opened in Excel It is highly recommended that after a time consuming analysis copies of all data files dat output files osh and monitor files mon should be kept together in a safe place preferably in a compressed format 142 ZeusNL User Manual ZBeer has the ability to plot past analysis results in the chart window when the corresponding output files are present in the same directory with the data files just after t
104. re exactly the same compressive and tensile strength crushing strain apart from the confinement factor 29 ZeusNL User Manual conci conz 2 2 0 002 conce conz 20 2 000Z 1 03 conca conz 20 2 000Z 4 Fig 19 Materials used in the static time history analysis New Section Section Name sec Section Type rcFws Reinforced concrete flexural wall section Section Material s Reinforcement Partially confined region Section Dimensions mm Wall width lona rei Y conc2 bad long rei 600 Unconfined region Fully confined region Confined width concl v cones 580 Wall thickness feo Confined area thickness Add Bar Edit Bar Delete Bar Reinforcing Bars Area mm d3 mm di mm 48 100 53 283 5 0 100 53 168 0 Height of fully confined region 56 55 56 0 160 Note Since the section is symmetrical about both the 1 and 3 axes only the reinforcing bars in the positive 1 3 quadrant should be defined The program generates the bars in the other three quadrants automatically Whenever a reinforcing bar lies on the 1 or 3 axis only half of its area should be specified Cancel Fig 20 The wall section used in the static time history analysis With these four materials the user can now define the wall section Fig 20 using the rcfws type and also define a cubic element class called wall with the new section and
105. res the last undone action Note there are some limitations in the names that ZeusNL uses for materials and sections element classes nodes and elements In ZeusNL material section element class node and element names may be up to eight characters long Moreover they should not contain spaces or the characters or amp Also note that cut materials can be copied and pasted Edit gt Copy and Edit gt Paste or using the pop up menus by right clicking on the table When a material meaning the entries for the description of a material in ZeusNL is pasted on the materials table if the name is the same with that of an existing material a star is added at the end of the pasted material name The material properties can be copied and pasted to and from other programs such as Microsoft Excel as long as the entries are consistent with ZeusNL format 2 1 3 3 Sections In this module the different sections of the model are specified There are 14 available section types including steel RC and composite For a complete description of the sections refer to Appendix B Each section is described by a set of sectional dimensions and if it is an RC section by the area and location of the reinforcing bars Like in the Materials module each section has a unique name and can be copied pasted and edited In the example ZeusNL has created two RC sections one rectangular called scol for the columns rcrs type and one T shap
106. riod elongation spectral amplification through the introduction of a site specific spectrum spread inelasticity and geometric nonlinearity of the members It performs better than the existing conventional methods especially in cases where strength or stiffness irregularities exist in the structure and higher mode effects are of importance A typical analysis involves the following 1 At each step before applying the extra load perform an eigenvalue analysis considering the stiffness state at the end of the previous step and calculate the periods and eigenvectors of the system The Jacobi method is used for this purpose 2 Based on the eigenvalue results and the shape of the selected spectrum the patterns of story forces for each mode are determined as follows F 1 0 M S 1 Where story number j mode number n total number of modes considered I modal participation factor for the j mode pj Mass normalized mode shape value for the i story and the j mode M mass of the i story S j spectral amplification of the j mode Whenever the spectral amplification is not considered the S j factor in 1 is replaced by the unity and 1 becomes F T M 1a In this case the lateral load pattern becomes spectrum independent and is defined only by the modal shapes of the system 3 After defining the lateral load profiles for each mode the values of the force distribution at each story level Fjare cal
107. run the analysis Save the project File gt Save and select Run gt Run or the corresponding toolbar button After performing some integrity checks the program starts running Depending on the size of the structure the applied loads and the PC processor the analysis may last for up to several hours This is significantly higher than the time required by other similar FE packages and it is attributed to the way the spread of inelasticity along member length and across section depth is modeled However the results have increased stability and significantly better accuracy ch feushL Analysis Fig 9 ZeusNL running dynamic analysis 20 ZeusNL User Manual 2 1 5 Getting the results ZeusNL has two different post processing facilities that supplement each other The Post Processor which creates curves with the action effects of the analysis displacement forces stresses etc and the deformed shape viewer with which the deformed structural shape can be viewed at the different time steps of the analysis Both open the basic results file type of ZeusNL num extension read them and display the data The user can run them from the corresponding commands of the Tools menu 2 1 5 1 Post processor The Post Processor is a facility used to easily derive diagrams with the results of the analysis For example the user is trying to plot the interstory drift between the top left node and the bottom left node of the first frame n151 a
108. s been already presented in detail in previous chapters both in its conventional and adaptive form The difference that ZBeer provides is the ability to run multiple practically unlimited static pushover files instead of one at a time and collect the user selected response parameters in separate files F 2 2 Dynamic pushover analysis The dynamic pushover approach is a special analysis technique where the structural system under consideration is excited by the same strong motion input scaled to different PGA values For every scaling factor the maximum response parameters shear drift moment curvature etc are plotted on a 2D plot just like static pushover curves The difference is that now each point represents a full run inelastic dynamic analysis whereas each point of the static pushover curve is simply a load step max d max V N e J o e e e e max d max V Lp ao He Hie He ihe Teg Ce ede Cac Fig F2 Implementation of the Dynamic Pushover approach 128 ZeusNL User Manual The selection of the dynamic response absolute maxima is an issue which requires further discussion regarding the fact that they may not occur in the same time instant For this reason ZBeer has the ability to collect not only the pair of absolute maxima Xmax Ymax for a response parameter but also the corresponding values of both response maxima Yor Xcor with an optional time step window
109. sNL User Manual Appendix D joint curves Appendix D describes the force displacement curves available to be used with the joint element 0D O0 0 O U DO DO lin smtr astr hsc hsv hfc hfv Elastic linear curve Tri linear symmetrical elasto plastic curve Tri linear asymmetric elasto plastic curve Hysteretic shear model under constant axial force Hysteretic shear model under axial force variation Hysteretic flexure model under constant axial force Hysteretic flexure model under axial force variation 114 ZeusNL User Manual In Elastic linear curve Number of parameters 1 This curve describes the elastic joint action characteristics parameter description typical value Ko Stiffness 1e5 displacement 115 ZeusNL User Manual smtr Tri linear symmetrical elasto plastic curve type Number of parameters 5 It is a typical tri linear symmetrical elasto plastic curve used to model the elasto plastic joint action Unloading is done kinematically to the extension of the second branch of the curve The stiffnesses Ko K and K must be positive whereas K and K should be less than Ko parameter Description typical value Initial stiffness Displacement where the stiffness changes from Ko to K4 Stiffness of second branch Displacement where the stiffness changes from K1 to Ko Stiffness of third branch x K ZZ jk edd BEES SN 7 i d d gt displacement ATEL K i A 116 ZeusNL User
110. specified in the Sections module Do not confuse the materials defined in this module with the material types available in ZeusNL libraries In this case there are two concrete materials conf and unconfined for the confined and unconfined concrete respectively with different properties but of the same material type con2 For a comprehensive description of the materials properties select one material and click the Edit button or simply double click on the material A window similar to Fig 4 will appear where the user can change the properties or even the type or the name of the selected material Apart from editing the existing materials it is easy to add a new material by clicking the Add button and selecting a name material type and the corresponding properties Moreover the user can remove the selected material s with the Remove button Edit Material Properties X Material Name font Material Type konz Cancel Non linear constant confinement concrete model Material Properties Compressive strength Nimm 0 Tensile strength N mm 2 fz 0 Crushing strain mm mm poz Confinement Factor iz Compressive Strain Fig 4 The Material Properties dialog box 11 ZeusNL User Manual lf by mistake the user removes one material well there is an Undo Redo facility in ZeusNL Simply select the Edit gt Undo menu command or the corresponding toolbar button and the material will be restored Edit gt Redo resto
111. ss Residual strength 91 ZeusNL User Manual typical value Tensile Strain ZeusNL User Manual Appendix B Sections In this Appendix a list of the available ZeusNL section types is presented a rss Rectangular solid section oO css Circular solid section a chs Circular hollow section a sits Symmetric l or T section a alcs Asymmetric L or C section O pecs Partially encased composite I section a fecs Fully encased composite I section a rers RC rectangular section a rccs RC circular section a rets RC T section a rcfws RC flexural wall section a rchrs RC hollow rectangular section a rchcs RC hollow circular section a rejrs Reinforce concrete jacket rectangular section 92 ZeusNL User Manual SS Rectangular solid section Number of materials 1 Number of dimensions 2 Width Height 93 ZeusNL User Manual CSS Circular solid section Number of materials 1 Number of dimensions 1 Diameter 94 ZeusNL User Manual chs Circular hollow section Number of materials 1 Number of dimensions 2 Diameter Thickness 95 ZeusNL User Manual sits Symmetric I or T section Number of materials 1 Number of dimensions 6 Bottom flange width Bottom flange thickness Top flange width Top flange thickness Web height Web thickness 96 ZeusNL User Manual alcs Asymmetric L or C section Number of materials 1 Number of dimensions 8 Bottom f
112. subtracting the end moments of the element and dividing by the element length V M2 M and hence the element length has to be specified as well 133 ZeusNL User Manual After pressing the Add Monitor button a new dialog window appears where the user must select the Story Shear Drift monitor type in the top of the dialog window al Figure F6 Story shear versus interstory drift monitoring Next the story shear has to be defined by S adding all story columns in a list This is done by entering each element name i Base Shear Drift along with its length in the corresponding editboxes and pressing the Add element button Accidentally entered columns can fC be removed by pressing the Delete EET Ea 6 Moment Curvature element button The Swap orientation a check box has to be checked in the rare TERS case in which the 2 axis of the column points downwards instead of upwards default Refer to appendix E for more details on the element orientation Finally the story shear direction must be specified for 2D structures the direction is always Vx whereas for 3D structures it can also be Vz The drift is specified by entering the up and down node names in the corresponding editboxes along with the displacement or rotation direction The resulting drift is d dup ddown Where dup and daown are the up and down node displacements or rotations respectively The snapshot at the left s
113. t Examples will clarify how the section local axes 1 2 3 relate to the global axes X Y Z and depict the details that one should pay attention to in order to have a correct modeling Assume there is a simple beam with a T section Fig E1 that the user tries to model Obviously the user will create two new nodes n1 and n2 that define its end nodes However n1 and n2 give no information for the T section and its orientation Fig E2 n1 Fig E1 Beam with a T section to be modeled Fig E2 Orientations of the T section of the beam 123 ZeusNL User Manual The third node of the element n3 serves exactly this purpose to define the orientation of the section Depending on the position of n3 the three nodes define one plane Fig E3 The rule is that the strong axis of the section 3 should lie within this plane Fig E3 The correct position of node n3 for modeling the orientations of Fig E2 In practice the user should follow this rule of thumb The vast majority of modeled structures are formed in plane frames For every frame in the x y or z y planes the user should create a non structural node that is not in the same line with any of the elements on the frame A good tactic would be to place the non structural node outside the limits of the structure The third node of every element of this frame will be this non structural node Good examples of this tactic are the models derived with the template as in Fig E
114. t Internal stirrup height Section width External stirrup width Internal stirrup width rnd mm ay r o l 106 ZeusNL User Manual Appendix C Elements The ZeusNL elements library contains a set of elements used to model the elasto plastic structural behavior the boundary conditions and the dynamic characteristics of the models Q Cubic Cubic elasto plastic 3D beam column element It is used for detailed elasto plastic modeling making use of the available uniaxial inelastic material models In accounts for the spread of inelasticity along the members length and across the section depth by dividing the cross section at the two Gauss points in a number of monitoring areas to which the material models apply Joint 3D joint element with uncoupled axial shear and moment actions The joint element is used to model pin joints inclined supports elasto plastic joint behavior soil structure interaction and structural gaps through employing appropriate joint curves Lmass Lumped concentrated mass element It models lumped masses It is used in dynamic and eigenvalue analysis Dmass Cubic distributed mass element It models uniformly distributed mass for dynamic and eigenvalue analysis Ddamp Dashpot concentrated viscous damping element Rdamp Rayleigh damping element It models Rayleigh damping effects in dynamic analysis of space frames 107 Cubic ZeusNL User Manual Cubic elast
115. t can also be VZ e Base Shear Britt Pa Story Smear Britt M Moment Curvature The drift is specified by entering the up and down node names in the corresponding editboxes along with the displacement or rotation direction The resulting drift is d dup ddown Where dup and daown are the up and down node displacements or rotations respectively The snapshot at the left shows a completed monitor dialog 132 ZeusNL User Manual By pressing OK the monitor is added in the list and its full description is displayed in the chart window Figure F5 shows an example of the correct definition of this monitor type 7500 fe es on was es Resen ae m aaen Base shear dem am ie a a 11114021141311 Direction Vx pa E E a lt q En mer A Global drift 3000 E n z a Up node n341 pO ope Down node n311 ale B d NE _ ane 4 so B Direction UX 1000 0 1000 2000 3000 4000 5000 6000 7000 8000 3000 Figure F5 Definition example of base shear vs global drift monitor Enter Monitor F 3 2 2 Story shear vs Drift The second monitoring option is the story shear V versus drift d figure F6 Horizontal shear forces V from columns of the same story are added and plotted against the displacement or rotation difference between two nodes usually at the top and the bottom of the same story interstory drift The element shear is calculated by
116. t them according to their x value A first click sorts the data in ascending order Clicking a second time will sort them in descending order Note for node and element identifiers the sorting is done according to the node number only if the nodes are in the format word number For identifiers in different format the sorting is alphabetical Adding items If the user clicks on the Add button a dialog box appears and the properties of the new table item can be selected The procedure is straightforward Note the same load can be added to many nodes at a single step since the Loads dialog box permits multi selection keep the Ctrl key pressed to select more than one node Also note for drop down lists with many items e g large models lists with nodes may contain hundreds of nodes if the user starts typing the name of the item desired ZeusNL will find the item Removing items The user can remove one or more items by selecting them and clicking the Remove button Editing Select one table item and click the Edit button alternatively double click on the item A dialog box similar to the corresponding Add dialog box opens and allows the user to change the properties Multiple editing is not allowed except for two cases editing the boundary conditions restraints of many nodes and changing the element class of many elements IF ZeusNL User Manual The user can change the element class of many elements by selecting them in th
117. t will look like Fig 46 63 ZeusNL User Manual 10 x File Edit Mode By Xx Fig 46 Data Entry Table There are two modes on the Data Entry Table the Editor mode that allows the user to enter change or delete data and the Selection mode that allows the user to make a selection and copy it Note data can be pasted to the table edited and then copied back After making the entries the data can be copied and pasted to ZeusNL main tables However make sure that the format is exactly the same with the required format 3 12 Getting the results 3 12 1 Post Processor The Post Processor allows the user to easily derive diagrams from the results of the analysis It runs with Tool gt Post Processor and allows the user to open the project results num file Note eigenvalue and static non variable loading analysis files cannot be read by the Post Processor After opening a project the user can select what is to be plotted in the x and y axes from the drop down lists on the left 64 ZeusNL User Manual Nodal displacements Nodal rotations Interstory drifts Support force Support moment Element shear force ODO oO O0 O U OU DO Time dynamic time history analysis Pseudo time static time history analysis or Load factor pushover analysis The nodes and elements are selected from dialog boxes that open after a selection is made from the drop down list In many cases the user will have to find
118. ted triangle v Figure F13 Dynamic Pushover File Dynamic 1 dat Monitor 1 Base Shear Vx n111 n211 n311 Drift Ux 1341 to n311 T J ee TY 7 Ta fe 2 vr sg 2a 4 64 4 44 4 4 a4 s s Base Shear KN tar Geens i 5 i 0 25 i i 0 4 0 45 se on A Corresponding BE steps Drift im Drifts Scaling Factors s oe s Se e e oe Sass Figure F13 Dynamic Pushover results maximum vs corresponding 141 ZeusNL User Manual Switching between these two available views is done by pressing the checkbox an the bottom left of the chart window and also select the size of the time step window up to 3 time steps The chart is automatically updated All the results depicted in the chart window can be exported for further processing in spreadsheet programs like Microsoft Excel For this reason right clicking in the chart window activates a popup menu which provides the user with the following options e Copy Chart to Clipboard With this option the chart is copied to the Clipboard as a bitmap image and can be pasted into any program which supports image objects Microsoft Word Adobe Photoshop CorelDRAW e Copy Values to Clipboard By clicking this option the numeric values of the displayed chart active data file and active monitor are copied to the clipboard and can be directly pasted into any spreadsheet program like Microsoft Excel for further processing Three columns a
119. the conventional pushover analysis the applied loads displacement forces or a combination of both vary proportionally according to a predefined pattern The post peak response is obtained with different displacement control procedures With the new adaptive pushover the applied load pattern is not constant but varies throughout the loading procedure in order to more accurately describe the stiffness degradation and the period elongation of the system a Static time history analysis The applied loads displacement forces or a combination of both vary independently in the pseudo time domain according to a prescribed load pattern a Dynamic analysis The applied load is usually acceleration at the supports although forces can also be used Both synchronous and asynchronous excitation can be modeled The Hilber Hughes Taylor or Newmark integration algorithms may be employed 1 2 How to Use this Manual This manual explains the operation and features of ZeusNL It has been separated into a number of sections which allows it to be used it as a reference guide as well as an initial tutorial on using the program To get started using this software follow the instructions later in this chapter which explain how to install ZeusNL Once the software is installed the rest of the program can be explored referring to Section 3 when necessary or by following the step by step Tutorials in Section 2 It is strongly suggested to follow the Tut
120. the y values multiplied with 1 10 Note the user can choose any value positive negative or even zero for the x and y multipliers With the Post Processor there are several diagrams that the user can easily create including nodal displacement and rotations interstory drifts support reactions element shear forces etc The diagram and values of the tables can be copied to other applications such as Microsoft Word and Microsoft Excel There are many options Tools gt Graph Options for the diagram and the user can change almost everything in its appearance including the background color thickness and style of the line axes labels and ticks etc Note the user can zoom in and out with the menu commands or the corresponding toolbar buttons To zoom in on a specific area select it by moving the mouse pointer from top left to bottom right By making a selection moving the mouse to the opposite direction from bottom right to top left the diagram zooms out to the initial state To remove the gradient of the graph go to the Panel tab of the Options window and uncheck the Gradient Visible checkbox The result is a plain graph with a white background ready to copy to a word processing application 22 ZeusNL User Manual 2 1 5 2 Deformed Shape Viewer With the Post Processor the user can quickly and easily create selected diagrams from an analysis and copy or print them However questions arise For example What happens whe
121. tics of the structure and the spectral shape The proportional loads have to be applied to nodes with masses otherwise they will not be considered in the analysis Moreover proportional loads cannot be displacements D ZeusNL User Manual it Classes Nodes Element Connectivity Restraints Applied Loading Loading Phases Adaptive Parameters Proportional Load nizi x Force 100000 Proportional Load nize x force 100000 Proportional Load n131 x force 100000 Proportional Load nliz x force 100000 Proportional Load ni4i x Force 100000 Proportional Load ni4z x Force 100000 Proportional Load n151 x Force 100000 Proportional Load n152 x Force 100000 Fig 53 Proportional loads for Adaptive Pushover analysis There is an extra control type in the Loading Phases module Adaptive Load Control This should be considered as a replacement of Load Control The input is the increment and the number of steps Fig 54 Classes Modes Element Connectivity Restraints Applied Loading Loading Phases adaptive Parameters Type of Control Mode Number Direction Displacement Limits Adaptive Load Control lg 100 Automatic Response Control n151 ba 0 600 Fig 54 Loading phases in adaptive pushover All the parameters needed in the method are defined in a new module called Adaptive Parameters These parameters are o Frequency Determines when the load distribution will be updated The default is 1 which means that the lo
122. to the material number selected For instance if the material selected is steel the Section Width should be the 136 ZeusNL User Manual maximum distance between the steel bars If the material selected is the confined region of a concrete column the width of the confined region must be entered and so forth Table F1 ZeusNL sections and material numbers By pressing OK the monitor is added in the list and its full description is displayed in the chart window F 3 2 4 Tips and tricks e The monitors list will apply to ALL files specified in the file list Therefore all structures in the file list must have the same node numbering element numbering and element lengths in order to obtain comparable results If this is not possible the user needs to specify different monitors for each group of different structures and ignore the non corresponding monitors for each group of structures after the analysis 137 ZeusNL User Manual e Node and element names which do not exist in the structure are ignored and their corresponding values are zeroed Therefore extra attention should be paid during the definition of base shear story shear and drift e Monitoring absolute displacements and rotations instead of drifts can be realized by assigning the Up Node to the node of interest and the Down Node to a non existing node name such as dummy the non existing dummy node yields to zero displacement or rot
123. to the structure In this way it is very easy to simulate asynchronous excitation by specifying the same curve with different delays 2 1 3 9 Applied Loading This module specifies the applied loads There are four different types of loads oa Initial These are static loads that are applied prior to any variable load They can be forces or prescribed displacements applied at nodes a Proportional These are static loads that have proportional variation The magnitude of a load at any step is given by the product of its nominal value which is constant and the current load factor which varies Proportional loads may be forces or prescribed displacements applied at nodes a Time history These are static loads varying according to different load curves in the pseudo time domain The magnitude of a load at any time step is given by the product of its nominal value which is constant and the variable load factor obtained from its load curve Time history loads may be forces or prescribed displacements applied at nodes a Dynamic These are accelerations or forces varying according to different load curves in the real time domain The product of its constant nominal value and the variable load factor obtained from its load curve at that time gives the magnitude of the load Dynamic loads can be forces or accelerations applied at the nodes in the global directions For this dynamic analysis initial loads applied at the structural masses and
124. tor CCDF First of all the coordinates of the vertical projection of each dynamic pushover point on the static pushover curve are defined shown in black Dynamic points with no projections on 144 ZeusNL User Manual the static pushover curve are ignored like D5 in the above example Then the difference between each projection point and the corresponding dynamic point in other words the difference of static with respect to dynamic analysis is calculated as follows Point D1 dp abs Yp1 Yor Point D2 dp2 abs Yp2 Yp2 Point D3 dp abs Yp3 Yp3 Point D4 dp4 abs Yp4 Yp4 Point D5 Ignored Yp1 abs 30 40 Ypo abs 45 30 Yp3 abs 50 40 Ypa abs 45 60 40 0 25 30 0 50 40 0 25 60 0 25 i NR N N i N N The final PP value is just the average of all above difference values PP 0 25 0 50 0 25 0 25 4 0 3125 31 25 Note again that point D5 does not participate in the above procedure because it lies beyond the horizontal span of the static pushover curve Moreover averaging all the differences from each pair of points means that equal weight has been assigned to each pair This is deemed to be realistic only when the scaling step of the record remains constant throughout the analysis which is always the case in ZBeer Finally the formula Yp Yp1 Yp1 was selected because the reference response denominator Yp1 is the dynamic response in
125. ture interaction and structural gaps a bLmass Lumped concentrated mass element used in dynamic and eigenvalue analysis a Dmass Cubic distributed mass element It models uniformly distributed mass in dynamic and eigenvalue analysis a Ddamp Dashpot concentrated viscous damping element used in dynamic analysis a Rdamp Rayleigh damping element It allows the use of Rayleigh damping modeling proportional to mass and stiffness in dynamic and eigenvalue analysis These element types are used to define element classes For a complete description of ZeusNL element types refer to Appendix C 3 5 1 Adding element classes As mentioned in Section 2 an element class is a number of properties referring to a particular element category Each element class has different properties depending on its type For example for cubic element classes the section of the elements should be specified together with the monitoring points in which the section is divided For Imass elements the lumped mass value should be specified for dmass elements the distributed mass value etc Adding an element class is accomplished with the Add button However the procedure is a bit more complicated than adding a section The New Element Class dialog box is similar to Fig 28 4 ZeusNL User Manual New Element Class i X Element Class Name Cancel Element Class Type Fig 28 New Element Class dialog box The drop down menu contains a
126. uted Mass Rayleigh Restraints Structural Modes Mon 5tructural Modes Structural Elements Labels Color FC visible Transparent Back Color Jw Shadow Jw Show Border Line Font le Show Border Frame Arr OS Visible Length f E Color General Background Close Fig 6 3D Plot Options dialog box Non Structural Nodes Try to navigate around the 3D Plot Options tabs There are numerous settings for the appearance of the model The user can change the color thickness and style of the lines size of the nodes and mass cubes insert titles and footers change the scale and show or hide the axes and the walls around the model The details of these settings are beyond the scope of this tutorial The only options that deserve a special attention are those on the General tab The 3D properties change the rotation location zoom and perspective of the plot Whereas the user may wish to uncheck the Automatic 3D Plot Update checkbox in cases where there are really large structures hundreds or thousands of nodes and elements and it takes several seconds for the program to update the view The view will update automatically every time something is changed If the option is unchecked the user can manually update the view from the pop up menu of the plot After having a look at the options close the dialog box Since the non structural nodes are not going to be needed any further the user may wish to make them invis
127. value that is the scaling factor and the curve name If the accelerogram is in g most common the value should be 9810 55 ZeusNL User Manual The scaling factor for transforming g to mm sec is 9810 The dynamic loads are usually accelerations applied at the supports they can also be forces The restraint at the support in the direction of the earthquake should be released xt y z rxtry rz becomes y z rxtry rz New Applied Load x Dynamic Time History Load List of Modes ee Cancel Direction xk Type acceleration Value fo ooo Curve Mame ri Fig 42 New dynamic time history load Finally the equilibrium stages of the analysis should be defined as in the previous section 3 10 ZeusNL Settings ZeusNL has a rich set of program settings that help the user optimize the efficiency and the performance of the analysis To open the Settings dialog box select Tools gt Settings 56 ZeusNL User Manual 3 10 1 General tab The General tab contains general settings for the program a Set as Default Program Defaults ZeusNL has a set of default program settings After installation these settings are loaded each time the user runs ZeusNL These settings have been thoroughly tested and proven to result in an optimal performance However the user may wish to use personal settings This is the objective of the Set as Default button that saves the current program settings as d
128. ve At this point it needs to be formatted 33 ZeusNL User Manual The moment units are currently in Nmm Go to the Tools gt Settings dialog box and change the y multiplier to 1e 6 or 0 000001 Now select Tools gt Graph Options and from the Panel tab uncheck the Gradient Visible checkbox In the Axis tab go to the Title sub tab for the left and the bottom axes and change the titles to Support Moment kKNm and Top Displacement mm respectively As a result there is a graph ready to copy to a word processing program It is not necessary to open a spreadsheet for the derivation of diagrams I ZeusNL Post Processor Ci Wtemp model4 num i ioj x File Edit View Tools Help ss Nodal Displacement Z Node 11 x direction x multiplier 1 WHS Support Moment B Supported Node 1 r2 direction multiplier 1 00E 006 View CURVE Nodal Displacement Support Moment em 0 6 76 2548 0 6 54 7244 2 90 9679 3 4 96 0199 4 8 100 393 6 2 104 74 76 111 706 5 123 334 10 4 136 855 11 8 147 841 13 2 155 741 E i 162 347 ii i gaa z 2 2 4 6 16 bed 2 Top Displacement mm 116 666 Support Moment kMm 3 Open Plot Settings Fig 27 Wall hysteretic curve 34 ZeusNL User Manual 3 RUNNING ZeusNL This section presents advanced features of ZeusNL that makes the user take advantage of the full potential of the program It will also help the user build
129. w Fw Parameters lin h 10000 Fz Fz Parameters in H fioo o Mx Mx Parameters 10001105100 My My Parameters Mz Mz Parameters Fig 30 New Joint Element Class Six curves have to be defined for the 6 DOF of the joint F F F2 M My M_ There are currently seven curve types in ZeusNL libraries E Q lin Elastic linear curve Number of parameters one smtr Tri linear symmetrical elasto plastic curve type Number of parameters five astr Tri linear asymmetric elasto plastic curve type Number of parameters ten hsc Hysteretic shear model under constant axial force Number of parameters twelve hsv Hysteretic shear model under axial force variation Number of parameters forty five hfc Hysteretic flexure model under constant axial force Number of parameters twelve hfv Hysteretic flexure model under axial force variation Number of parameters forty five For a complete description of the curves refer to Appendix D For each of the six curves there is a drop down list of the available curve types Selecting each one of them opens a new dialog box for defining the parameters of each curve Fig 31 44 ZeusNL User Manual New Element Class x Add Curve Properties smir x Element Class Name ficlass ee Initial stifness Ko 1000 Element Class Type joint 130 joint eleme Displacement do Fx Fx Parameters r lin 10000 Fy Fy Parameters znd branch stifmess lin sd
130. xperimental data to determine these parameters 85 ZeusNL User Manual con Trilinear concrete model Number of properties 4 It is a simplified concrete model for uniaxial modeling property description typical value Initial stiffness Compressive strength Degradation stiffness Residual strength Li i iW JE gt Compressive Strain 86 ZeusNL User Manual con2 Uniaxial constant confinement concrete model Number of properties 4 Uniaxial modeling of concrete assuming constant confinement It is considerably more accurate than con1 property description typical value Compressive strength Tensile strength Crushing strain Confinement factor Stress Eco Compressive Strain I Tt 87 ZeusNL User Manual con3 Uniaxial variable confinement concrete model Number of properties 10 Uniaxial modeling of concrete It accounts for the variable confinement effects which are influenced by the core area within the stirrups the stirrup size and material and the Stirrup spacing property Description typical value Concrete compressive strength 20 Concrete tensile strength 2 2 Concrete crushing strain 0 002 Poisson s ratio of concrete 0 2 Yield stress of stirrups 500 The Young s modulus of stirrups 200000 Strain hardening parameter of stirrups 0 005 Diameter of stirrups 10 Stirrup spacing 100 Diameter of concrete core 300 Stress Compressive Strain ft 88 ZeusNL User Manu
131. y Curve Discrepancy Factor CCDF and will be discussed in detail later on 130 ZeusNL User Manual F 3 2 The Monitor List After the file selection comes the most important procedure before the fully automated analysis provided by ZBeer The selection of response monitors and creation of the monitor list Before presenting all different itor 2 Story Shear Drift i ee ee Story Shear Drift monitor types and creation steps in detail it is noted that fap ia Sloe Shear DAL at this stage the user can load an already prepared list itor 5 Moment Curvature i Moment Curvature of monitors stored in the form of a mon file This can be tor Te Hermes Gurvatlire done by pressing the Open monitor list button and eau eee select the monitors file In the same way when a itor 10 Curvature monitor list is ready the user can store it in the disk by Sue sede Curvature pressing the Save monitor list button and enter a monitor 13 Moment Curvature preferred filename The monitors file mon is written in plain text format and can be edited with any text editor like notepad for easy corrections or modifications However it has a strict syntax and extensive editing may result in serious errors New monitors can be added by pressing the Add monitor button indicated by the plus sign Similarly removing an existing monitor from the list can be done by pressing the Delete monitor butto
132. y in the pseudo time domain The applied load P in a nodal position is given by P J O P as a function of the time dependent load factor 1 t and the nominal load P This type of analysis is typically used to model static testing of structures under various force or displacement patterns e g cyclic loading 3 1 6 Dynamic time history analysis In dynamic analysis non structural mass and damping elements are added to the FE model as required to solve the dynamic equation of motion Modeling of seismic action is achieved by introducing acceleration loading at the supports Further the ability to employ different loading curves at each support allows for representation of asynchronous ground excitation 3 1 7 Switching between analysis types a Whereas the cubic and joint elements can be used for every analysis type mass elements dmass and Imass are not needed in static analyses Therefore they can be used only in dynamic eigenvalue and adaptive pushover analysis Moreover damping elements ddamp and rdamp are only needed in dynamic analysis a In dynamic analysis the DOF of the support in the direction of the earthquake should be released so that the acceleration input can be applied For example if a node is fully supported x y z rx ry rz and the earthquake is applied in the x direction the x restraint should be released y z rx ry rz If there is earthquake input in both x and y directions the supported DOF
133. y in the pseudo time or time domain The innovative Adaptive Pushover Procedure In this pushover method the lateral load distribution is not kept constant but is continuously updated during the analysis according to the modal shapes and participation factors derived by eigenvalue analysis carried out at the current step In this way the current stiffness state and the period elongation of the structure at each step as well as higher mode effects are accounted for E ZeusNL User Manual Integration with the Windows operating system environment Data can be pasted to the ZeusNL input tables from spreadsheet programs such as Microsoft Excel whereas everything that may appear in the program windows can be copied back e g to word processing programs such as Microsoft Word including input and output data high quality graphs the models deformed and undeformed shapes and more Moreover AVI movie files can be created describing the sequence of the structures deformed shapes With the new Template facility the user can create regular or irregular 2D or 3D models and run all types of analyses in a few seconds Advanced post processing facilities for deriving graphs and deformed shapes easily and efficiently ZeusNL User Manual 2 TUTORIALS This chapter will walk the user through the first analysis types of ZeusNL ZeusNL was designed with both ease of use and flexibility in mind The goal is to run analyses even d
134. y the bars in the positive 1 side for the T section The program 12 ZeusNL User Manual generates the rest of the bars Finally if the user clicks the Ok button the reinforcing bars are arranged on the Section Reinforcement table entry in trinities of As d3 d4 Edit Section Properties i x Section Type frets Reinforced concrete T section Section Material s Section Dimensions mm Reinforcement i v conf hd rein E 200 Unconfined region unc Section Name Fbear Confined region Siar a Beam height 600 Add Bar Edit Bar Delete Bar Confined height in slab 150 Reinforcing Bars areata dsm army mn 775 0 1250 Confined height in beam Slab effective width Beam width 300 Confined width in slab Note Since the section is symmetrical about the 3 axis only 1200 the reinforcing bars in the positive 1 side should be specified The program generates the bars in the other Confined width in beam side automatically Whenever a reinforcing bar lies on the 3 axis only half of its area should be specified The 250 origin For 3 axis is the bottom of the section cancel Fig 5 The Section Properties dialog box 2 1 3 4 Element Classes The ZeusNL element library contains a set of elements used to model structural elements beams and columns non structural elements mass and damping and boundary co
135. ynamic time history analysis in just a few minutes It is actually much easier to use ZeusNL than it is to describe Once the user has become familiar with a few important concepts the entire process is quite intuitive Although the whole process will last no longer than a few minutes the model that is created has many features and can efficiently and accurately simulate real structures For many people this is all the functionality they will ever need by ZeusNL Section 3 goes into further detail about all of the powerful features of ZeusNL and more ways to increase productivity 2 1 Tutorial 1 Dynamic Analysis It is assumed hereinafter that the user is trying to model a 3D four story RC structure and run dynamic time history analysis for a specified record It is also assumed that the structure is regular has two bays and consists of two parallel frames The bay lengths are 5m the story heights are 3m and the distance between the two frames is 4m ZeusNL User Manual 2 1 1 Structural configuration To open the Template window select File gt Create from Template menu command or click on the Template button of the toolbar The user will be presented with a screen full of options about the structural configuration Open Template E x Reference Dimensions Bay Length mm 5000 Storey Height mm 3000 Distance between Frames 5000 Number of Bays Ok Cancel f S Number of Storeys f f S
136. ysis With displacements rather than forces applied the descending branch of the curve may be derived O One Response Control phase forces applied As mentioned earlier the applied variable load is forced on selected nodes but the analysis checks convergence taking into account the displacement at the controlled node 3 9 3 Applying loads for static time history analysis The variable loading consists of displacement forces or a combination of both which vary independently in the pseudo time domain according to a prescribed load pattern The load pattern is defined in the Time History Curve module The user can either load or create a new curve Usually static time history analysis is used to model simple cyclic tests on specimens In these cases the loading curve is fairly simple so the user will need to define it rather than load it By contrast in dynamic analysis the applied curve is usually an accelerogram that is loaded in ZeusNL To create a new curve click the Create button This brings the user to the New User Defined Curve dialog box Fig 37 Input the pseudo time and load factor values in the table on the left Use Enter or Tab to move to the next cell or line and specify a name for the curve The name will be used in the Applied Loading module to use the defined load pattern Note the values and the graph can be copied or printed with the pop up menus right clicking on the table and plot New User Defined Curve X

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