ATENA Example Manual - Cervenka Consulting
Contents
1. _Assign Entities Draw Unassign Close Figure 2 24 Assigning condition of point displacement to a mesh node 26 LInazsi All conditions mmo E mr T Field s color Thiz condition Colors Conditions lo Nae 2 Displacement 0 0 Assen Entities Draw Point Displacement Displacement Y Displacement U 0 Dic placement Displacement 001 NE PSTN p r m En O MET TR 5 NS en Pm TEE CACERES SARS SEPTA TRA Swen S ARA OT PRG OM a S NISSEN NEN SU SP NS gt TT a pm O T 7 N m ur FECE EOS NE SC d PE A AN PA RA HA KERA SIIN DS 34 TE VEST SHOPY NGI Figure 2 25 View and inspect a condition in a mesh node If we want to inspect the assigned values we can do it by clicking on the button Draw and select Field value Z Displacement Then the assigned condition value appears at the concerned node See Figure 2 25 2 1 7 Monitoring points Analogically to the Section 2 1 5 it is also possible to specify the monitoring points directly on the finite element mesh The monitoring points are tools to record a structural response for example a load displacement diagram In GiD we can for instance specify only force and displacement monitoring at a mesh node This is done also in Conditions For applied force we select Force Monitor for reaction force Reaction Monitor for nodal displacement Displ2. 7 Global Settings Time and Transport Restart Calculation from Calculated Step Title Pipe T askM ame Pipeb Method Displacement Error 0 0001 Residual Error 0 0001 Absolute Residual Error 0 0001 Energy Error 0 000001 Iteration limit 30 Optimize width Sloan Stiffness type Tangent Predictor Assemble Stiffness Matris Each teration Solver LU Extend Accuracy Factor Line Search Method i Conditional Break Criteria Step Stop Displacement 100000 Iter Stop Displacement 100000 Step Stop Residual 100000 Iter Stop Residual 100000 Step Stop Energy 100000 Iter Stop Energy 100000 Master Slave Distance 1 0E 4 Extrapolation Nearest IP Show Surface Loads In Post Processor Write Monitor Data Close Problem Data E k dj Global Settings Time and Transport Restart Calculation from Calculated Step Time Integration of Transient Theta of Crank Nicholson 0 7 I Export Transport Results Export Results Ta PipeB He Export Geometry Tao PipeB Ger Close Figure 3 6 Problem data dialog including the definition of temperature exchange files with stress analysis The problem data dialog that is shown in Figure 3 6 can be opened via the menu item Data Problem data This dialog can be used to define the basic parameters for the 39 thermal analysis The most important fields can be found at the bottom of the Time and Transport tab where the names of two files are to be specified Th
3. N Figure 2 10 Selected volumes are highlighted by red colour 17 A 9 ON LAT ostat 53G 83 203 BE E K KANU J s E n p YA NT N a NUN Nr x p LIN P a 8 LESE y Reinforced Concrete 5 Figure 2 11 Assignment of the material Cantilever2 18 z B Cantilever1 u B Cantilever2 Figure 2 12 Display of the assigned material groups A composite material for the second part of the structure named as Cantilever2 can be defined in a similar way where the only difference is in the value of reinforcement ratio Figure 2 11 2 1 4 2 Bar reinforcement From the menu Data Materials we select the material Reinforcement which is designated for discrete bars There we choose from the list the ATENA model CCReinforcement and then click on the button New reinforcement and enter the name for the reinforcement material After confirmation by OK a dialog for material parameters appears The parameters include initial elastic modulus yield strength and optionally points on the stress strain curve The last parameter is the bar cross sectional area see Figure 2 14 The material is then assigned to the geometry by pressing the button Assign and selecting line geometric entities by the mouse The selected bars are marked by red color Figure 2 15 Applying the command Draw at the bottom of reinforcement material dialog see Figure 2 16 can check a correct assign
4. Reinf 01 f3 Reinf 01 eps4 Reinf 01 f4 Reinf 01 eps5 Reint 01 f5 Iv Calculator Profile Number of Profiles R01 To recalculate click Update hanges next to material box 2x please Area 201 06192982 mm Assign Unassign Exchange Figure 2 14 Material parameters for the Reinforcement model 20 Figure 2 15 Assigning material to the geometry of bars Reinforcement CC1DElastlsotropic Basic Miscellaneous Element Geometry Material Prototype CC1DElastlsotropic Young s Modulus E 2 1E 5 MPa Poisson s Ratio MU 0 3 Calculator R01 To recalculate click Update TTT box 2x please changes next to material box 2x please Area 0 000201061 m Assign Draw Unassign Exchange CC1DElastlsotropic All materials A Figure 2 16 Display of the reinforcement material assignment 21 2 1 5 Supports and loading The supports and loading can be a specified using the menu Data Conditions We define the fixed nodes by checking X Y Z Constrains and the type of geometry Surface Using the command Assign we select the end face of the cantilever and finish the assignment of support conditions In a similar way we assign the Point displacement at the node of load application The load is applied as a vertical imposed displacement Consequently the force value is a reaction at this node Conditions Constraint for Surface Basic Coordinate System GLOBAL iw Constraint
5. Draw output z A ELEM TEMPERATURE INCR ELEM TOTAL TEMPERATURE Max U x 576 006 ELEMENT ORIENTATION Location cus AN EQ PLASTIC STRAIN muy 5 FRACTURE STRAIN Global nodes MmUy 0 Max U z 1e 010 Mm U z 1e 010 ae ob PERFORMANCE INDEX C Elements PLASTIC_STRAIN 4 4 PRINCIPAL_FRACTURE_STRAIN Elements IPs m Mu Y 12 PRINCIPAL_PLASTIC_STRAIN ars PRINCIPAL STRAIN Bm Y 0 PRINCIPAL STRESS Mex Zo 1e 010 RATE FACTOR Item Min Z le010 RATE FACTORS ET SOFT H RD PARAMETER STR L TENSILE_STRENGTH Cancel TOTAL_ELEM_BODY_LOAD v vi DINE E M NECS Apply Hi gt Filter DK mn F PipeBStatic msg ECTS AJ EIX 1 1 1 0 21 0 052 0 21 NR 2 1 0 014 0 017 0 0041 0 00023 NR 3 1 0 0011 0 0013 0 00032 1 4e 006 NR Step 1 completed Elapsed CPU sec this step 3 282 all steps 3 282 Job Step 2 Log start 26 2 2009 12 28 11 Iter Eta Disp Err Resid Err Res Abs E Energy Err HR Iter Eta Unbalanced Energy Ratio Current Required L3 1 1 0 5 0 11 0 026 0 054 NR m Ready Back substitution BEE Dof Blk 500 Time 2 2 OVR Total Commander P cc seminar 2008 taj Tutorial Atena Eng GiD Atenav4 Stat E Calculator AtenaWin JM CCSt Figure 3 13 Execution of static analysis in AtenaWin and the selection of crack opening display 46 sy Be W z z 44 Ce Es WU Gp EE d N CAM Oe u e Le ED E Set 1 C
6. GID T utorial T emperature2D PipeB Static gid amp tenaR esults inp File written OK Command tram amp Total Commander M cc seminar 2008 m Tutorial Atena Eng GiD tenav4 Stat E Calculator cx CHWINDOWSISyS Figure 3 16 Importing results for postprocessing in GiD 49 London Tokyo Moscow Su VES V 4 Dil Versions g EBU Ein ON Ne By S yk X So MW ES I I 4 V Ux a Postprocess Read Directory Cx AtenaCalculation E AtenaResults flavia msh NF GENS O IO I P fs a Eevee FIND File name AtenaResults flavia res Files of type GiD postprocess res msh bin w Cancel y b File written OK Al Enter name of file to read E Command Total Commander 7 0 P cc seminar 2008 09 ta Tutorial Atena Eng Te GiD AtenaV4 Static FE Calculator Figure 3 17 Opening results for postprocessing in GiD The results can be then postprocessed Figure 3 18 shows crack width as contour lines which can be selected by the menu command View results Contour lines CRACK WIDTH COD1 The command can also be accessed from the S icon 50 H M o9 gt 1 t amp ersion w d Qo anf D LT Oi KM ino Me J LED amp RR FFE HE IO ZIP II eu za E o oc BAD zn O O onh 00O 3 gt a a a U tep 50 Contour Lines of CRACK WIDTH CO
7. Search Method Line Search With Iterations Line Search With Iterations Unbalanced Energy Limit 0 8 Line Search Iteration Limit 3 Mirun Eta 0 1 Maximum Eta 1 Conditional Break Criteria Close Problem Data Global Settings Global Options Transport Restart Calculation from Calculated Step iw Import Transport Results Import From Results PipeB He Import From Geometry FipeE Get Close Figure 3 11 Problem data dialog including the definition of temperature exchange files The loading history 1s specified in a single interval The interval is divided into 50 load steps In each step the temperature difference of 720 seconds from the thermal analysis 44 is applied Figure 3 12 So the interval spans the period of 10 hours 1 e 1t only covers the heating phase The Transport Import switch set to Interval Beginning means the thermal analysis results are only imported once and the temperature values are interpolated for each static analysis step For complex temperature histories not well approximated by a linear interpolation throughout the interval e g fire analysis this should be changed to Each Step Then the thermal results are imported in each load step and the temperature fields are interpolated from the 2 nearest transport analysis steps Interval Data n z fo Basic Parameters Eigenvalue Analysis iw Interval ls Active Load Name temp load Interval Multiplier 1 0 Number of L
8. iw Constraint iw Z Constraint Assign Entities Unassign Figure 2 17 Definition of the surface support in all directions Conditions Displacement for Point USE decimal peint DO NOT use comma ent 0 0 m A Displacem Y Displacement 0 0 m Displacement 4 0005 m Assign Entities Draw Unassign Figure 2 18 Definition of prescribed displacement in vertical direction The conditions dialog of GiD can be also used to define ATENA monitors These are special type of conditions that does not affect the analysis results They are merely used to monitor certain quantities during the analysis In this example the following monitors will be specified e Maximal crack width e Displacement at the point of load application e Reaction at the point of load application The definition process of the above conditions and monitors 1s described in Figure 2 20 The resulting assignment of the boundary conditions can be checked using the command Draw All Conditions Exclude local axis which can be located at the bottom of the Conditions dialog It should be noted that it is also possible to apply these conditions directly on the 22 generated finite element model but then the regenerated Conditions MaxMonitor for Volume Data Attribute CRACK WIDTH ltem t all Global MM MAXIMUM 4 Location NODES Draw Each Iteration IdentificationByName Monitor ame M axCragssl Assign Entities Un
9. terms of intervals in GiD In the first interval the supports are defined as well as the two vertical forces The first interval should represent the application of the permanent load In the subsequent interval this load will be kept constant and the material will creep causing the deflections as well as cracking increase The application of the permanent load is expected to cause some cracking therefore it is subdivided in 20 steps The application of the permanent load will start at the time of 63 days and it will be completed at 63 02 days In the second interval no additional forces are applied therefore only supports are defined for this interval The interval starts at 63 02 days and continues up to the stop time i e 365 days defined in Data Problem Data This interval is represented in ATENA by only a single step ATENA automatically inserts substeps if it determines that one load step would not be sufficient for such a long time period Monitoring points Monitoring points are chosen in order to describe a load displacement response as well as the long term behavior In ATENA GiD interface the monitoring is defined as conditions Data Conditions The monitoring defined in this way is considered only if specified in the first interval The definition of monitoring points in subsequent intervals is ignored In this example always the applied force is monitored as well as the mid span deflection Run Analysis can be started eith
10. this dialog various variables can be selected for 40 display The temperature fields can be displayed by selecting CURRENT_PSI_VALUES Temper File Edit fe Toms pot UTE a Propet es ppt zia zd 488 0 16 B z mg S U A HH N TB PARBWITN SESE SH L AA S e Le 25x B E Set 1 ConvergenceMonitor Seg E Geometry PE Convergence criteria 1 4 5 9963132 4 4372343 2 9981566 m Available data m General CURRENT NODAL COORDINATES Draw output CURRENT PSI VALUES DISPLACEMENTS EXTERNAL_FORCES Location INTERNAL FORCES Uy NODAL_DEGREES_OF_FREEDOM Global nodes Uy 0 1 4990783 NODAL_SETTING C Max U z 1e 010 NONE Element nodes Mn U z 1e 010 PARTIAL EXTERN L FORCES c l PARTIAL_INTERNAL_FORCES Eee Mer 12 PARTIAL REACTIONS Elements IPs x 0 PARTIAL_RESIDUAL_FORCES F gt T A Relative error 0 0 0 REAL le 010 REACTIONS Item 0 REFERENCE_NODAL_COORDINATES RESIDUAL_FORCES v START PSI VALUES 21600 000 64800 000 86400 000 Cancel Apply Filter OK F PipeBTemp msg OVX Iter Rel Humid Rel Temper Abs Humid Abs Temper i 0 1 7 0 6 2 0 9 1e 015 0 5 2e 014 Step 13 completed Elapsed CPU sec this step 1 672 all steps 20 857 Ready Completed Time 8 6e 004 2 OVR Figure 3 8 The selection of temperature display in AtenaWin 41 S for item Temper File Edi VICW VY LIUIUS JU UL LI LT quy Prue MALI Jui C
11. with totally different meshes 35 b Figure 3 1 Geometry and material properties of the axisymmetrical pipe model PES ELLE EER III IR III R BOK BK S O R Z x DOM RIA 6 X SN RER SN RLY VERY ROK SORIA KKK SA OK Say ceu Coen dur e ER gui A HH mE S Figure 3 2 Numerical model finite element mesh The loading is subdivided in 3 intervals In the first interval 12 load steps are defined with boundary conditions as described in Figure 3 3 In each step the temperature on the outer surface is increased by 1 C see Figure 3 3 The temperature in the exterior is 36 increased up to 37 C starting from the initial uniform 25 C Each step in this interval represents 3000 seconds thus the whole interval covers the period 0 36000 seconds 0 10 hours b Figure 3 3 Boundary conditions for the interval 1 In the subsequent interval 2 the temperature at the outer surface is kept constant This interval contains 10 steps 2880 seconds long This means the whole interval spans the time period from 36000 64800 seconds 10 hours 18 hours b Figure 3 4 Boundary conditions for the interval 2 37 In the last interval 3 the outer surface is cooled back to 25 degrees This interval contains 12 steps 1800 seconds long This means the whole interval spans the time period from 64800 86400 seconds 18 hours 24 hours b Figure 3 5 Boundary conditions for the interval 3 38 Problem Data EJ k
12. 2666 HU 6 2 6 Figure 2 34 Deleting materials in interval 2 In the next step we need to create the lining with non linear concrete material We switch the current interval to No 3 In menu Data gt Conditions gt Conditions for surface we choose Elements Activity for Surface and select Construction Elements Activity CREATE WITH NEW MAT Figure 2 35 and choose the CC3DNonLinCementitious2 material We can create specific material for this case and assign to surfaces which we want to create Figure 2 36 33 Conditions Elements Activity for Surface Using for Construction State for 30 Geometries without Shell L anstruction E lements Activity CREATE WITH NEW MAT Assign material material for linning Entities Unassign Figure 2 35 Condition for surface create new material M CREATE WITH NEW HA T CC3DNonLinCement itious E 34266 Figure 2 36 Creating concerete lining In the last step Interval No 4 we will only add load to top of the model Data Conditions Conditions for line Load for line 2 2 3 Running analysis Analysis can be run by selecting button in menu Calculate Calculate or clicking on the EE button E ATENA Calculate and in AtenaWin by clicking on button Execute 34 3 TRANSPORT ANALYSIS 3 1 Combination of Thermal and Static Analysis An example demonstrating the coupling of thermal and stress analyses 3 1 1 Introduction This document describes an example of r
13. 52 Dir of pl flow BETA 0 0 MN RHO Density 0 023 m mE B m Assign Unassign Exchange Figure 2 7 Concrete component in the Reinforced concrete material Reinforced Concrete BON Basic Concrete Comp 0 CCSmearedReinf 01 CCSmearedReinf 02 Element Geometry Reinf 02 Material Prototype CCSmearedReinf Reinf 02 Young s Modulus E 2 1E 5 MPa Reinf 02 Reinforcing RATIO p s c 0 0025 Reinf 02 Dir X of the smeared reinf D Reinf 02 Dir Y of the smeared reinf 1 Reinf 02 Dir Z of the smeared reinf Jo Reinf 02 Yield Strength YS 400 MPa Reinf 02 Number of Multilinear values 2 Reinf 02 eps2 0 2 Reint 02 f2 400 MPa Reif 02ep30 Reint 023 0 MPa Reinf O eps4 Rein 02 0 MPa Reinf 2eps5 D Reint 025 0 MPa MN Reinf 02 RHO Density 0 0785 m m Reinf 02 Thermal Expansion Alpha 0 000012 Assign Unassign Exchange Figure 2 8 Components of smeared reinforcement in the composite material 16 Reinforced Concrete EJ OE 75 v 8 Basic Concrete Comp CCSmearedR eint 01 CCS mearedBeinf DZ Element Geometry Material Prototype CCCombinedM aterial W Activate SmearedReinf 01 Wo Activate SmearedReinf 02 Activate SmearedReinf 03 Assign Draw Unassign Exchange Paints Close Lines Surfaces Volumes Figure 2 9 Menu item Assign Volumes f V Y n V pe 7 A M XN A
14. AL STRAIN STRESS PRINCIPAL STRESS TENSILE STRENGTH FRACTURE STRAIN PRINCIPAL FRACTURE STRAIN MAXIMAL FRALT STRAIN CRACK WIDTH PERFORMANCE INDEX PLASTIC STRAIN PRINCIPAL PLASTIC STRAIN SOFT HARD PARAMETER EQ PLASTIC STRAIN REFERENCE NODAL COORDINATES amp 1 tt 10 1101 d 8 amp 8 sl a s S I Il s sla Llose Figure 3 15 Selecting results for postprocessing in GiD 48 The menu command ATENA GiD Post processing or the lt gt icon toggles GiD between pre and postprocessing A warning about non existent res file may appear then a console windows 1s started and the results are converted into a format readable by GiD see Figure 3 16 The conversion can take a few minutes depending on model size number of load steps and the number of quantities selected for postprocessing The results are stored into the AtenaResults flavia res file in the AtenaCalculation respectively AtenaTransportCalculation directory for static analysis respectively transport analysis This file can be opened in GiD by the File Open command see Figure 3 17 Local LA N Y London Tokyo Moscow Delhi Singapore Sydney UTE a x E SGI OSS 4 bil Versions WSO eB ine a ff v 9 Iw E SNE SNE EO DI b 4 ca C WINDOWS system32 cmd exe ENA RABEN Im S TR Ez S Dm x pem w I oni 9 Ame E Si y b File written to C X amp tenaE amp amplessAtena
15. CERVENKA CONSULTING Cervenka Consulting s r o Na Hrebenkach 55 150 00 Prague Czech Republic Phone 420 220 610 018 E mail cervenka cervenka cz Web http www cervenka cz C ATENA Program Documentation Part 3 2 Example Manual ATENA Science Written by Vladim r ervenka Jan ervenka and Zden k Janda Prague April 10 2014 Trademarks ATENA is registered trademark of Vladimir Cervenka GiD is registered trademark of CIMNE of Barcelona Spain Microsoft and Microsoft Windows are registered trademarks of Microsoft Corporation Other names may be trademarks of their respective owners Copyright 2000 2014 Cervenka Consulting s r o CONTENTS 1 CREEP ANALYSIS 1 1 1 1 1 1 1 2 1 1 3 1 1 4 Long term deflection of a reinforced concrete beam Introduction Comments on FE model preparation Results References 2 STATIC ANALYSIS 2 1 2 1 1 2 1 2 21 3 2 1 4 21 5 2 1 6 2 3 2 1 8 2 1 9 2 2 22 1 22 2 2 3 Example of a static analysis with reinforcement Reinforcement modelling Problem type and data Geometry Materials Supports and loading Meshing Monitoring points Load history Analysis and post processing Tutorial for Construction Process Introduction Geometry boundary conditions and load Running analysis 3 TRANSPORT ANALYSIS 3 1 3 1 1 3 1 2 3 1 3 3 1 4 3 1 5 3 2 Combination of Thermal and Static Analysis Introduction Thermal Analysis Stress Analysis Postproc
16. D1 Contour Lines ICRACK_WIDTHI Min 0 Max 1 88e 005 Contour Lines COD1 Min 0 Max 1 88e 005 Figure 3 18 Displaying crack opening displacement isolines in GiD 3 1 4 2 Postprocessing in ATENA 3D The highest user comfort for post processing 1s provided by ATENA 3D After executing ATENA 3D the result file for each increment can be loaded into the program by using the menu File Open other Results by step This command activates a dialog that can be used to load ATENA binary files with results to ATENA 3D postprocessor When the user finishes loading the needed result file and closes the dialog ATENA 3D postprocessor is automatically started It should be noted that it 1s possible to open only binary result files that come from the same analysis For further details about post processing the user should consult the Part 2 2 of ATENA user s manual 2 3 1 5 Conclusions This tutorial provided a step by step introduction to performing combined thermal and stress analysis using ATENA software with GiD preprocessor The tutorial involves an example of an axisymmetric pipe heated from the outside from 25 to 37 C in 10 hours Then the heating remains constant for another 8 hours and 1s afterwards cooled back to 25 C in 6 hours 51 The objective of this tutorial 1s to provide the user with basic understanding of the program behavior and usage For more information the user should consult the user s manual 2 or co
17. Elastic modulus 210 Yield strength perfectly plastic Table 1 1 3 Finite element mesh Finite element type CCIsoQuad CCIsoBrick Quadrilateral Hexahedral isoparametric isoparametric Element shape smoothing N A Gibbs Poole Gibbs Poole Table 1 1 4 Solution parameters Number of iterations PD Prost nosn k AaB Pohled V ztu 4x610 mm 10505 R Kryt 30 mm Zat en F 6 9 kN Figure 1 1 Geometry of the reinforced concrete beam Figure 1 2 Two dimensional geometrical model with reinforcement loading and boundary conditions in GiD Figure 1 4 Three dimensional geometrical model with reinforcement loading and boundary conditions in GiD Figure 1 5 Three dimensional finite element model 10 UJ DJ U NO Cn Vitek2D Vitek3D Experiment A Experiment B Total middle deflection mm U 0 60 90 120 150 180 210 240 270 300 330 360 Time days Figure 1 6 Long term mid span deflection Comparison of two and three dimensional analysis with experimental data 2 STATIC ANALYSIS This chapter contains examples of static analysis using the program ATENA Currently some commands required for static analysis are not supported by the native ATENA graphical environment and therefore the necessary commands must be entered manually or by using the ATENA GID interface
18. GiD see the Internet address http gid cimne upc es 1s a general purpose finite element pre and post processor that can be used for data preparation for ATENA See the README TXT file in the ATENA installation for the instructions how to install the ATENA interface to GiD In order to activate the creep analysis option an appropriate problem type must be selected Data Problem type AtenaV4 Static 2 1 Example of a static analysis with reinforcement In this example we demonstrate the usage of GiD for data generation of a simple structure The structure is a reinforced concrete L shaped cantilever It has fixed supports on one end and is loaded by vertical force near the free end See Figure 2 1 The first beam adjacent to the fixed end 1s subjected to a simultaneous action of bending and torsion while the second beam 1s only under bending A complex three dimensional behaviour can be well analysed by ATENA and for this purpose the input data can be prepared in GiD 2 1 1 Reinforcement modelling The longitudinal reinforcement is by bars 4028 that are located long the edges and by stirrups 612 with spacing 100mm in the first beam section A and with spacing 200mm in the second beam section B 11 Since there are different possibilities to model reinforced concrete we make first a decision about the modelling approach Concrete shall be modelled by 3D brick elements For this we chose the hexahedra elements The longitudinal reinf
19. IL SU 1888 0 18 2 Beste a 5x B Sw nM Eg OL aa cO e Le ET E Set 1 ConvergenceMonitor X E CURRENT PSI VALUES at location NODES for item Temper Convergence criteria 14 CURRENT PSI VALL 5 9963132 Temper 33817 33688 33558 33429 44972348 333 33 17 33041 32912 32782 2 9981566 Relative error Max U_x 0 Min U x 0 Max U_y 0 Min U y 0 1 4990783 Max U z 1e 010 Mm U z 1e 010 Max X 21600 000 64800 000 86400 000 lt F PipeBTemp msg a Ele Iter Rel Humid Rel Temper Abs Humid Abs Temper Step 13 completed Elapsed CPU sec this step 1 672 all steps 20 857 I Ready Completed TE Time 8 6e 004 2 OVR 16 m Mob O win 8 Sky S Inb Sof GID a te ore oy ca Tut GID Figure 3 9 The runtime display of temperature field during the thermal analysis in ATENA After the thermal analysis s completed AtenaWin can be closed All resulting files are stored in the subdirectory AtenaTransportCalculation of the PipeBTemp gid directory In this subdirectory the following files will exist after the completion of the thermal analysis PipeBTemp inp ATENA input file created by GiD and used by AtenaWin PipeB 00xx Binary result files created by ATENA during the thermal analysis These two files are created in the Tutorial Temperature2D directory PipeB Results thw Saved temperatures to be used by stress analysis PipeB Geometry bin Saved geomet
20. acement Monitor Displacement component is selected by checking the appropriate box 27 a NARA PC Es PTS SSS VSE BEL PSESTRIN 11 1 511 5 STRES SIS PS S TAJ KRJ S Er m ERN V ASSA Ta rn m rn 4 x E E E Pul P waco R IO OSS ERT O E y VOSK R AO S OSE MBAR SV KA N A LO Z je T MA BAARIA x 9 l mene NN x E REACTIONS Finish to end selection AL I Meet pike eee A Wannen sh Fress Finish ta end selection Figure 2 26 Definition of a monitor for reaction at node Output Data DISPLACEMENTS mi T Draw Each Iteration 2 B Z u i LI B CI Monitor far Paint Output Data Monitor for Paint Figure 2 27 Definition of monitor for displacement at node node An inspection of monitors can be done by the command Draw in the same manner as in For analysis in ATENA a load history as a sequence of load steps must be defined The load steps can be proportional or non proportional In this example the load history is simple We other conditions The monitoring points must be included within Conditions of the first load interval in GiD Figure 2 26 and Figure 2 27 show definition of force reaction and displacement monitors at a Monitors included in other intervals will not be active in ATENA analysis 2 1 8 Load history 28 define first interval which includes a set of conditions for supports at the f
21. allation Figure 2 3 The model of the discrete bars Since the smeared model of stirrups does not exactly represent their geometry it is alternatively possible to use discrete bars as well This 1s case 1s not described in this manual but it can be found in the data file Demo L Bars finite element model with supports and loading Figure 2 4 Final the problem definition starts by choosing an appropriate problem type by selecting in Data Problem Data Both steps were already described in Chapter 4 However the the menu item Data Problem type Atena V4 Static and then the general solution data parameters of Problem Data can be also changed later 2 1 2 Problem type and data Typically 2 1 3 Geometry The geometry is created by using the GiD graphical tools from elementary objects sequentially starting from points lines and finally surfaces and volumes We start with the definition of points Points are connected to lines From lines we can form surfaces and from surfaces we can form volumes solid objects Details of this input shall be skipped since it belongs to standard GiD functions The final geometrical model is shown in Figure 2 5 Note that it contains two types of objects volumes for concrete and reinforced concrete and lines for the discrete reinforcement In GiD it is also possible to create volumes directly from predefined primitives as shown in the figure on the right which indicates the ava
22. applied in the L7 transport material model in ATENA GiD The main problem of casting arches of the bridge was development of considerable hydration heat Therefore at early times the arch s segments had to be cooled down by circulating water in six Steel pipes The cooling to mitigate temperature gradients in the segment was turned off after roughly 40 hours after casting Figure 3 20 shows the temperature field at 0 20 40 100 hours of the hydration time The heat transfer coefficient was estimated as 10 W m K on the surface of the beam and air temperature was assumed constant at 25 C The casting occurred during summer season when high ambient air temperatures contribute to excessive temperatures in the beam Prescribed temperature 17 C was imposed on all inner nodes which were in contact with a cooling pipe After approximately 40 hours the cooling nodes were incorporated in a vector of unknown temperature field and computed The results of the analysis show that due to the cooling it was possible to keep the concrete temperature well below 90 C This value is considered to be the critical temperature after which the concrete properties may start to deteriorate and may impair the quality and durability of the structure Figure 3 19 Arches of the bridge over Oparno valley The simulated segment is approximately above the scaffolding 53 Temperature 65 60 639 51918 Oh 20h 40 h 100 h Figure 3 20 Temperature field
23. assign Conditions Monitor for Point Output Data DISPLACEMENTS M Dix DirY Iv DirZ Draw Each Iteration MonitorN ame Disp2 LH s LONE LIN Assign Entities Draw Unassign IN N Conditions Monitor for Point REACTIONS Output Data Di DirY Iv Diz Draw Each Iteration MonitorName A X NJ S Ll applied conditions are lost every time the mesh 1s Assign the crack width monitor to all volumes z P Assign the displacement monitor to this point Hl Na S DISS DN L4 O LE i S M N 3 L TERN NY NA TE AW Assign the reaction monitor to this point Assign Entities Unassign Figure 2 19 Definition of the ATENA monitors 23 gt GiD Atena 3 Static 3D Interface ODB Ro a S PV 9 amp 4 Dil Versio Applied displacement and two monitors for deflection and reaction monitoring N I p Dip Use Draw All Conditions Exclude local axis to display conditions E NA N axMonitor for Volume IN NE A Figure 2 20 Display of assigned conditions In certain cas
24. er directly from GiD or by typing the following command AtenaWin M CCStructuresCreep It is important to specify the M option in the command line when invoking the AtenaWin program This activates the creep module and various creep commands If the M option is not used various syntax messages are obtained 1 1 3 Results The results from the analysis are documented in Figure 1 6 where the calculated long term mid span deflection is compared with the experimental data obtained by Dr Vitek It shows that without any specific calibration the model predicts well the long term deflections 1 1 4 References 1 ATENA Documentation Part 1 ATENA Theory Manual Cervenka Consulting 2003 2 ATENA Documentation Part 6 ATENA Input File Format Cervenka Consulting 2003 3 ATENA Documentation Part 8 User s Manual for ATENA GiD Interface Cervenka Consulting 2003 Table 1 1 1 Material properties of concrete Material type a Creep material CCModelB3 pm d Lu Thickness i e ratio of volume m to 0 05138 surface area m of cross section Cylindrical compressive strength f 46 75 after 26 days MPa Density kg m 2 370 kg Base material CC3DNonLinCementitious2 Elastic modulus GPa 34 200 MPa Compressive strength MPa 46 75 Tensile strength MPa 3 257 Fracture energy N m Compressive plast def m 0 0005 Table 1 1 2 Material properties of reinforcement Material type Reinforcement 11
25. es it may be advisable to manually identify which line entities represent reinforcement By default the ATENA GiD interface attempts to treat all lines that are not connected to any surface or volume as reinforcement This default behavior is activated by the corresponding check box in the Problem Data dialog In certain cases the automatic identification does not work properly In this case it is advisable to deactivate this default behavior un assign all reinforcement node and element identification and then assign it again manually These two conditions should be manually assigned to all reinforcement line entities 1f Conditions Renforcement Modes Identification eight for Reint Line Temperature for Heinf Line Initial Strain for Heinf Line Initial Stress for Heinf Line Fixed Contact for Line Reinforcement Hodes Identification Reinforcement Elem Identification Entities Figure 2 21 Manual identification of reinforcement nod Unassign error messages about reinforcement identification appear during mesh generation or during the generation of the ATENA input file Prior to that the automatic reinforcement identification check box should be deselected and all reinforcement identif Conditions unassigned 24 2 1 6 Meshing In the preceding description the geometry was defined and all properties material supports loading were assigned to geometry Now we shall generate a finite element mesh For this we must s
26. ese files are used for exchanging the temperature fields with the subsequent stress analysis By default the files would be stored in the AtenaTransportCalculation subdirectory of the main problem directory inserting before the names writes them into the Tutorial Temperature2D directory The ATENA calculation is started from the menu ATENA ATENA analysis or by clicking the calculator icon CI This will start AtenaWin program which is a graphical interactive environment for the execution control of ATENA finite element core module More details about the usage of this program can be found in the corresponding ATENA manual 5 After executing ATENA analysis the following window appears on the user s computer see Figure 3 7 zy 468e 8e m J5 jm z 34 TE m ww n BE NOC AB a 4 U e Le b x A E Set 1 ConvergenceMonitor 0 mE E Geometry Convergence criteria 1 4 Relative error ll F PipeBTemp err mE ATENA Version 4 1 3 2241 c Cervenka Consulting 1998 2008 Ready Assembling Stiffness Internal Forces Group 463 Elem 204 Time 6e 003 1 OYR Figure 3 7 The main AtenaWin window after its activation from GiD The ATENA analys s s started automatically or by clicking the button This starts the thermal analys s n AtenaW n environment In order to visualize the development of the temperature field the button S can be selected and this will open a dialog that 1s shown in Figure 3 8 In
27. essing Conclusions Heat and Moisture Transport Analysis incl Hydration 4 LITERATURE ii SINAN Ul 10 10 10 17 13 14 21 24 26 21 28 29 29 30 34 34 34 34 42 46 50 52 55 1 CREEP ANALYSIS This chapter contains examples of creep analysis using the program ATENA Currently the commands required for creep analysis are not supported by the native ATENA graphical environment and therefore the necessary commands must be entered manually or by using the ATENA GID interface GiD see the Internet address http gid cimne upc es 1s a general purpose finite element pre and post processor that can be used for data preparation for ATENA See the README TXT file in the ATENA installation for the instructions how to install the ATENA interface to GiD In order to activate the creep analysis option an appropriate problem type must be selected Data Problem type AtenaV4 Creep 1 1 Long term deflection of a reinforced concrete beam Keywords reinforced concrete discrete reinforcement creep Input files EXAMPLES GID CREEP2D VITEK2D GID EXAMPLES GID CREEP3D VITEK3D GID 1 1 1 Introduction This example demonstrates the application of ATENA system to the creep analysis of a reinforced concrete beam The analyzed beam was tested by Dr Jan Vitek from Metrostav corp Czech Republic 1 1 2 Comments on FE model preparation General data The problem is modeled by two models two dimensional one and t
28. et up appropriate parameters in the menu Meshing Meshing w Mormal Quadratic Quadratic Quadratic elements Assign unstuck sizes Structured Mesh criteria Element type Boundaries r Fr F F Da Draw sizes d Reset mesh data Cancel mesh Generate Ctrl g Mesh view Ltrl m Mesh quality Edit mesh d Figure 2 22 Meshing menu 2 1 6 1 Mesh definition for volumes concrete First we shall deal with the meshing of volumes concrete There are many ways how to define mesh In this case we use a simple method in which divisions on all lines are defined If opposite lines have the same division we can create a regular mesh e In the item Quadratic elements we define low order elements by checking Normal e In Structured we define division on all lines It is always sufficient to select one line GiD automatically assigns the same division to all opposite edges e In Mesh criteria we select lines e In Element types select Hexahedra 2 1 6 2 Mesh definition for lines reinforcement It is important to realize that lines of reinforcement in GiD serve only to export geometry to ATENA The embedded reinforcement will be generated in ATENA This means that we should make the line elements of reinforcement as large as possible If we use division into a single element then this single element is then passed to ATENA for the generation of the individual bar segments Finding the intersections of the reinforcement bar
29. hree dimensional In both cases the geometrical model Figure 1 2 and Figure 1 4 is created in such a way to facilitate the generation of purely structural meshes 1 e meshes that are composed of only quadrilateral and hexahedral elements in 2D and 3D respectively 1 1 2 1 Reinforcement If program GiD is used for pre processing the reinforcement can be modeled in two ways smeared reinforcement can be modeled by Reinforced Concrete material or by discrete bars Discrete reinforcement bars are modeled as line curves These lines should be meshed by as few elements as possible Typically one truss element per line is sufficient ATENA then automatically determines the intersection of these lines with the 3D model and places reinforcement embedded elements into each segment that is created by this process 1 1 2 2 Materials When creep analysis is requested the material for which creep should be taken into account must be modeled by one of the creep materials see the ATENA Theory Manual 1 or ATENA Input File Format 2 Within the creep material a base concrete material is defined which is one of the standard ATENA materials Currently only following materials are supported as creep base materials CC3DNonLinCementitious2 CC3DbiLinearSteelVonMises or CC3DDruckerPragerPlasticity Material properties used in this example are listed in Table 1 1 1 and Table 1 1 2 1 1 2 3 Topology and loading The loading history 1s defined in
30. ilable list of predefined primitives such as rectangle circle sphere etc The volumes can be also created by extrusion which is activated from the GiD menu Utilities Move or Copy In this dialog various copy operations can be selected such as rotation translation sweep There is also a check box which activates the extrusion Figure 2 5 Geometrical model amp S le AA Noeea0 e 13 14 2 1 4 Materials The materials can be defined and assigned to the geometry using the menu item Data Materials Recommended procedure is to keep the default material unchanged for later reference and create any number of user defined materials Since we intend to model the vertical stirrups by smeared reinforcement we shall use the material type Reinforced concrete CCCombinedMaterial is a default material and Cantileverl Cantilever2 are user defined composite materials that are created from the default material by pressing the button Li This command creates a new material of the same type which can be assigned a suitable user defined name see Figure 2 6 Reinforced Concrete x Cantilever hd i CS s k a Basic Concrete Comp U CCSmearedR eint 01 LCS mearedB einf U Element Geometry Material Prototype CCCombinedM aterial r i Activate SmearedReinf 01 i Activate SmearedReinf 02 Activate SmearedReinf 03 The smeared reinforcement components are activated using these checkboxes When selected new prope
31. in the left symmetric part of the beam The dimensions of displayed cross section are 3 5x2 17 m The beam is cooled down by water Figure 3 21validates the simulation and shows relatively good match between calculated and measured temperature at particular times Nevertheless one has to mention that several details regarding conditions of casting process and other important data were unknown and they were just estimated in the analysis This applies particularly to a detail description of sequence of the casting procedure 80 70 60 50 40 30 Concrete temperature C 10 Simulation Experiment 0 20 40 60 80 100 Hydration time h Figure 3 21 Validation of multiscale model on the segment 4B of the Oparno bridge The cooling was turned off at 40 hours in the simulation The above paragraphs brings description of the presented problem of the Oparno bridge from the engineering point of view including a brief validation of the calculated results The next part of this Section explains the sample analysis from the point of ATENA GiD modelling It concentrates mainly on input of transport material parameters used by the L7 material model 54 popis zadam ulohy modelovam okraj podminek vcetne casoveho prubehu vlastn material popis integrace v case integrace alpha maturity factor popis chlazen behem betonaze atd sample input data info o narocich a cene vypoctu CPU time 55 4 LITERATURE 1 ATENA Program Docume
32. is 3 1 4 Postprocessing Postprocessing can be done either in AtenaWin GiD or ATENA 3D Normally AtenaWin displays the current step that is analysed After the analysis 1s finished the last step remains in AtenaWin memory and can be visualized and further post processed In case the user wants to post process results from other load step the corresponding step results file is to be opened using the command Application Restore FE Model From The step data file name is task name 00xx where task name 1s the name of the current task as given in the problem data dialog see Figure 3 11 and 00xx represents the load step number which 1s to be post processed 47 Alternatively the new text window is to be opened using the menu item File New Please note that a text window must be highlighted in order to another text window If graphical window is the active one a new graphical window will be opened Into the new text window the following command shall be written RESTORE FROM task name 00xx 3 1 4 1 Postprocessing in GiD To be able to postprocess the results in GiD the result quantities must first be made available by selecting them in the Data Problem Data Post Data dialog see Figure 3 15 Post data x DISPLACEMENTS PARTIAL INTERNAL FORCES INTERNAL FORCES PARTIAL E amp TERNAL FORCES EXTERNAL FORCES PARTIAL REACTIONS REACTIONS PARTIAL RESIDUAL FORCES RESIDUAL FORCES PHYSICAL PARAMETERS STRAIN PRINCIP
33. ixed end and point displacement This can be checked and changed in the menu item Data Interval Data Next load steps can be done in two ways The simplest way is to enter the number of repeated load steps and multipliers in the window of Interval Data Figure 2 28 which is a proportional load history In case of a non proportional history for example first a vertical load followed by a horizontal load we can use Data Interval Data Default settings of calculation method and global settings are in Data Problem Data All conditions will be multiplied by a factor Interval Dat i S 1 MERE ae 1 0 in all load steps generated in this interval ai LOAD NAME Load LOAD STEP Muliiplier 0 Results from all steps will be saved Each step Store data for this IntervalSteps SAVE ALL is saved in a Separate file which is named l TaskName xxx where xxx denotes the step W Generate Multiple Steps Number of LOAD STEP 50 number 50 load steps will be generated All with the INTERVAL STARTING TIME 0 0 day same conditions INTERVAL END TIME 0 04 day 50 These data fields are editable only the import User Solution Parameters of transport data 1s requested in Problem Data dialog Close Figure 2 28 Interval data definition 2 1 9 Analysis and post processing The non linear analysis is started by the menu item Calculate or icon Ci This causes the data from GiD to be written into an input file for ATENA INP a
34. lus This gives a bi linear elastic plastic law with unlimited ductility A general multi linear function can be defined by additional points Maximum 4 additional points can by given Up to three smeared reinforcements can be defined in one composite material This limit exists only in the GiD interface ATENA can define unlimited number of components for a single composite material in this case it is necessary to manually edit the ATENA input which is generated by GiD 15 After the parameter definition the material can be assigned to the structure This is done by the button Assign and following the appropriate selection by mouse The process of selection is a general operation and it allows for selecting of points lines surfaces and volumes In this case the material should be assigned to volumes of geometry Figure 2 9 Figure 2 10 Reinforced Concrete Cantievert z e X Basic Concrete Comp 0 CCSmearedReinf 01 CCSmearedReinf 02 Element Geometry Base Material Prototype CC3DNonLinCementitious2 YoungsModulusE 14E 4 MPa Poisson s Ratio MU 02 TensionstrenghFT 218 MPa Compresion strenath FC 34 0 MPa N M Fracture energy GF 7 018e 5 pa Fixed Crack 0 7 jv Activate Crack spacing Crack spacing 0 2 m IV Activate Tension stiffening Tension stiffening 0 4 Plastic strain EPS CP 0 0009968 Onset of crushing FCO 7 0 MPa Critical comp disp wD 0 0005 m Excentricity EXC 0
35. ment which shows the geometry in this case lines with the currently assigned material In case of pre stressed bars each bar cable must have a distinct material even if its values are identical with other bars The reason for this is to distinguish among groups of elements for pre stressing The pre stressing is defined in Conditions Lines Initial strains and is assigned to the lines that model the pre stressing reinforcement New reinforcement x Enter new reinforcement name Main reinf Figure 2 13 New material for bar reinforcement o Reinforcement Main reinf 020 Basic Miscellaneous Element Geometry Material Prototype CCReinforcement Reinf 01 Young s Modulus E 2 1E 5 MPa Reinf 01 Yield Strength YS 400 MPa Reinf 01 Number of Multilinear values 2 Reinf 01 eps2 0 2 Reinf 01 f2 400 MPa Reinf 01 eps3 T Reinf 01 f3 0 Reinf 01 eps4 0 Reinf 01 f4 0 Reinf 01 eps5 0 Reinf 01 f5 0 MPa MPa MPa Calculator Profile 20 mm Number of Profiles 1 R01 To recalculate click Update hanges next to material box 2x please Area 314 159265358 mm Assign Unassign Exchange Reinforcement Main reinf 016 v ZB ES aX Basic Miscellaneous Element Geometry Material Prototype CCReinforcement Reinf 01 Young s Modulus E 2 1E 5 MPa Reinf 01 Yield Strength YS 400 MPa Reinf 01 Number of Multilinear values Reinf 01 eps2 Reinf 01 f2 Reinf 01 eps3
36. nd the program AtenaWin is started During the execution of AtenaWin variety of intermediate results can be viewed and inspected The results of analysis can be presented in the program ATENA 3D The Post processing in ATENA 3D is started via menu ATENA ATENA 3D post processing Then it is necessary to import the binary result files TaskName xxx from the required load steps into ATENA 3D This is accomplished through the ATENA 3D menu File Open other Results by step For operation of AtenaWin ATENA 3D or any other details of ATENA software see the ATENA Documentation 29 2 2 Tutorial for Construction Process 2 2 1 Introduction The objective of this tutorial is to show how the graphical environment of GiD can be used to model the construction process The finite element solution core of ATENA supports the possibility to add or remove groups of finite elements This feature can be used to model the construction process in GiD The ATENA GiD extension of the GiD graphical environment includes direct support for this feature This feature can be modeled using the conditions for surface and it will be demonstrated n this manual on the example of a tunnel see Figure 2 29 Soil Lining Soil Air Figure 2 29 Model with three macro elements The basic idea of the construction process modeling in ATENA is the following It is possible to add or remove finite element groups at any time 30 2 2 2 Geometry boundary conditi
37. ntact the program distributor or developer Our team 1s ready to answer your questions and help you to solve your problems The theoretical derivations and formulations that are used 1n the program are described in the theory manual 1 Experienced users can also find useful information in the manual for the analysis module only 4 52 3 2 Heat and Moisture Transport Analysis incl Hydration This Section brings an example of heat and moisture analysis within ATENA GiD framework Its primary goal is to demonstrate how concrete hydration can be considered in the analysis Both development of hydration heat and moisture consumption due to hydration are accounted for The analysis also shows use of FIRE BOUNDARY load condition It is employed to simulate radiation of generated heat within the structure to the ambient air Heat and moisture transport analysis is carried out to analyze a segment 4B of the bridge over the Oparno valley see Figure 3 19 The bridge is located on the highway between Prague and Dresden The segment length is 5 6 m width 7 0 m and height 2 2 m and falls in the category of mass concrete element That s why the interest in hydration heat The casting took place during August 2009 The multiscale model is used The microscale analysis of the evolution of hydration heat was accomplieshed by CEMHYD3D model Having the results the affinity hydration model has been calibrated and the calculated material parameters were
38. ntation Part 1 ATENA Theory Manual CERVENKA CONSULTING 2009 2 ATENA Program Documentation Part 2 1 and 2 2 ATENA 2D and 3D User s Manual CERVENKA CONSULTING 2008 3 ATENA Program Documentation Part 3 ATENA 2D Examples of Application CERVENKA CONSULTING 2005 4 ATENA Program Documentation Part 6 ATENA Input File Format CERVENKA CONSULTING 2009 5 ATENA Program Documentation Part 7 AtenaWin Manual CERVENKA CONSULTING 2008 6 ATENA Program Documentation Part 8 User s Manual for ATENA GiD Interface CERVENKA CONSULTING 2008
39. oad Steps 50 Store Data for this Interval Steps SAVE ALL Fatigue Interval ML iw Read Transport Data Transport Import INTERVAL BEGINNING Interval Starting Time 0 hour Interval End Time 10 hour Iv Delete BC Data After Calculation User Solution Parameters Close Figure 3 12 Interval data for the interval 1 The stress analysis is again started by selecting the menu item ATENA ATENA analysis or the icon This starts the AtenaWin program The analysis 1s started automatically or by clicking the button This starts the stress analysis in AtenaWin environment In order to visualize the development of the various data fields the button j can be selected and this will open a dialog that 1s shown in Figure 3 13 In this dialog various variables can be selected for display The contour areas of crack width can be displayed by selecting Elements CRACK ATTRIBUTES COD1 The resulting computer screen in shown in Figure 3 14 45 The imported temperature values can be displayed as ELEM_TOTAL_TEMPERATURE TotalTemp Please note that only the difference from the reference initial temperature is displayed in static analysis A be London Moscow sd 884880 88 9 AB si 317 eo dg xb EB 9 9 59 0x EE SF OL a 4 U Pl x m E Set 1 ConvergenceMonitor Seg E Geometry LEGEND Geometry 5 re Post processor data v gt s Available data M General z 3 Iv
40. ons and load We need to analyze a structure of a tunnel Around the tunnel there is concrete lining Boundary conditions are seen in Figure 2 30 Monitor for Point Monitor points Conditions Constraint for Point Dead Load Basic Coordinate System GLOBAL Iv X Constraint jw Y Constraint Z Constraint Assign Entities Draw Unassign Constraint for Point Colors Exclude local axes Only local axes Field s color gt Include local axes All conditions Field s value gt Figure 2 30 Draw all conditons on model The construction should proceed as follows l excavation of a circular hole in the soil 2 adding lining ring 3 adding load First it 1s necessary to construct the model of the whole structure Three separate macro elements will be created for all four intervals For each of these macro elements it is necessary to have one separate material Interval 1 this interval is used to define the basic boundary conditions to support the model from the bottom and both sides Interval 2 this interval is used for excavation of a circular hole in the soil by deleting two centered macroelements Interval 3 this interval is used to add lining ring shape with concrete material characteristics around the hole Interval 4 this interval is used to add load to top face of the model At the beginning the whole area consists of soil however we must define separate mac
41. onvergenceMonitor EX E CRACK WIDTH at location ELEMENT NODES for item COD1 EIER LEGEND Convergence criteria 1 4 1 0000000 al 2 7094e 007 23708e 007 2 0321e 007 16934e 007 0 7500000 13547e 007 1016 007 6 7736e 008 3 3868e 008 L e 0 u v 2 05000000 x 5 3 v9 Z n Max U x 12e 005 Mn U x Max U 12e 005 Mn U_y 0 0 2500000 Max U z 16 010 Mm U z 1e 010 Wx 12 Min X 0 Mm 12 Min Y 0 Max Z 1e 010 Mm Z le 010 s s s Mux Val 2 7e 007 e e e s s s Min Wl 0 e e e e e e M lt gt BEES Job Step 4 Log start 26 2 2009 12 30 50 Iter Eta Disp Err Resid Err Res Abs E Energy Err HR Iter Eta Unbalanced Energy Ratio Current Required L3 1 1 0 26 0 39 0 13 0 099 NR 1 1 0 82 0 8 LS 2 1 0 0076 0 32 0 11 0 0024 NR 1 1 0 85 0 8 L5 3 1 0 0095 0 27 0 094 0 0026 NR 1 1 0 86 0 8 LS 4 l 0 0079 0 23 0 082 0 0018 NR 1 1 0 86 0 8 LS 3 5 1 0 0068 0 2 0 072 0 0014 NR Ready Assembling Group 233 Elem 492 Time 4 6 OVR Sasa SSS BYR I I Z K I TG 1L 1LCA Figure 3 14 Execution process of stress analysis in AtenaWin showing the crack opening displacements After the completion of the analysis the AtenaCalculation subdirectory of PipeBStatic gid contains the following files PipeBStatic inp ATENA input file created by GiD and used by AtenaWin PipeBStatic 00xx Binary result files created by ATENA during the stress analys
42. orcement shall be modelled by discrete bars The stirrups shall be modelled as a smeared reinforcement within the reinforced concrete composite material This is a simplified method by which we avoid an input of detail geometry of stirrups In smeared model the exact position of individual stirrups is not captured and only their average effect 1s taken into account The resulting model is shown in Figure 2 2 The colours of elements show two types of materials used the composite material named Cantileverl in the short beam and Cantilever2 in the longer beam The discrete bars are modelled by linear elements as shown in Figure 2 3 In the following we shall treat the generation of the model in more details A data file with this example can be found in the ATENA installation under the name SmallCantileverWithTorsion DiscreteBars gidTutorial Static3D in the subdirectory Atena Examples Tutorial Static3D Section A Section B Figure 2 1 L shaped cantilever beam Dimensions in mm E Cantilever1 Cantilever2 H Hain Reinf Figure 2 2 The model with two composite materials Cantilever 1 and Cantilever 2 12 J ASRS Ao P PEN S Zl u k i 11T pm Bd STK RUSSIAN SS STN M EI 1 d u a Earn y E RM SL LESE RANK r I 1 pei fe UNTAN NA AAAS d SU NTN SECTEUR a ue o ee SK Al dl SA NE CLES E gid enclosed in the ATENA inst
43. otationally symmetrical vessel subjected to thermal loading The analysis is performed using the programs ATENA and GiD ATENA 1s used for thermal and static analysis and the program GiD 1s used for data preparation and mesh generation The programs GiD and ATENA can be installed using the standard ATENA installation At the end of the installation the user must select the installation of GiD and ATENA GiD interface After that your computer should be ready to run the example problem described n this document 3 1 2 Thermal Analysis First the program GiD 1s started The recommended version 1s 9 0 4 or newer the oldest supported version is 7 7 2b After starting GiD the user should open the example analysis ATENA Science ATENA G1D Tutorial Temperature2D PipeBTemp gid This 1s an existing model demonstrating the combination of thermal and stress analysis This problem is using the problem type AtenaV4 Transport It represents a section of a pipe wall with thickness of 0 23 m and internal diameter of 1 m Taking advantage of the symmetry only a quarter of the whole cross section is modeled The geometry of the model is shown Figure 3 1 and the numerical model 1s shown in Figure 3 2 Details about ATENA GiD interface and associated problem types for ATENA can be found in the manual 6 The same mesh size 1s used for thermal and static analysis This 1s however not a strong requirement The thermal loading can be exchanged also between models
44. roelements for future changes soil lining air We assign the soil material to all these macroelements for the first interval Figure 2 31 The additional intervals will be needed for the subsequent phases of the construction process 3l Figure 2 31 Material for interval 1 In next step excavation we need to remove both circles from the center It can be made using conditions for surface In menu Data Interval Current we switch to interval No 2 which we want to edit Figure 2 32 In menu Data Conditions Conditions for surface we choose Elements Activity for Surface and select Construction Elements Activity DELETE Figure 2 33 Next we can Assign areas which we want to excavate Figure 2 34 We can draw all macroelements which have assigned some conditions by choosing Draw Colors Figure 2 34 Enter value window Figure 2 32 Switching current interval 32 Conditions Elements Activity for Surface Using for Construction State for 2D Geometry except Shell L anstructien E lements Activity DELETE Assign Entities Unassign Figure 2 33 Conditions for surfaces Conditions Elements Activity for Surface Using for Construction State for 2D Geometry except Shell Construction Elements Activity DELETE Assign Entities Draw Unassign cl Elements Activity for Surface Colors All conditions Field s value Field s color a DELETE CC3DNonLinC ementitious2 E 3
45. rty sheets appear in the dialog Assign Unassign Exchange Figure 2 6 Reinforced concrete material Two composite materials created 2 1 4 1 Reinforced concrete as composite material First we define parameters of concrete component This can be done by selecting the tab Concrete Component 0 and modifying its parameters There are several choices available for the basic material It is recommended to select the material CC3DNonLinCementitious2 which is identical to the same material from the group Concrete The dialog window is extended to allow additional reinforcement components The buttons ol ol allow changing adding new and deleting of materials When adding a new material with the button e the default material 1s first copied then re named and edited The stirrups are modelled by smeared reinforcement as Component 1 of the composite material The first 5 parameters describe the initial elastic modulus reinforcing ratio and direction The reinforcing ratio of smeared reinforcement is calculated as p A A where As A are the section areas of bars and concrete respectively in the considered volume This ratio is different in each part of cantilever due to different stirrup spacing The direction of the smeared reinforcement 1s defined as a unit vector The constitutive law of the reinforcement is defined as multi linear by a sequence of points stress strain pairs The first point is defined by yield strength and elastic modu
46. ry to be used for the interpolation of temperatures 1n the stress analysis 42 3 1 3 Stress Analysis After the thermal analys s is completed AtenaWin can be closed and the stress analys s can be performed using the calculated thermal fields A new GiD problem must be created or the existing problem PipeBStatic gid can be used This model defines the input for stress analysis of the same pipe wall as was used in the thermal analysis The geometrical model and boundary conditions are shown in Figure 3 10 e Figure 3 10 Geometrical model and boundary conditions for stress analysis In order to be able to utilize the thermal fields calculated during the thermal analysis the appropriate import files must be specified in the problem data dialog that 1s activated from the menu Data Problem data and is shown in Figure 3 11 This information is located in the bottom 2 input fields where appropriate file names are specified including their path 43 Problem Data Ed k 47 Global Settings Global Uptians Transport Restart Calculation from Calculated Step Title demo default title for Static analysis T askMame PipeB5tatic Method Mewtan Haphson Displacement Error 0 01 Residual Error 0 01 Absolute Residual Error 0 01 Energy Error 0 000 Iteration Lirit BU Optimize Band width Sloan Stiffness Type Tangent Predictor Assemble Stiffness Matix Each iteration solver LU Extend Accuracy Factor iw Line
47. with the solid elements generates the segments In case the reinforcement in GiD is modelled using curved lines then it 1s recommended to prescribe a certain division to finite elements such that the curved geometry of the bar 1s properly represented 25 Enter value window X Enter number of cells to assign to lines Figure 2 23 One division in lines of reinforcement n the item Quadratic elements we define low order elements by checking Normal n Structured define 1 division on lines Figure 2 23 In Mesh criteria select lines In Element types select Linear Lines 2 1 6 3 Mesh generation By selecting the item Generate the mesh is automatically generated The mesh can be inspected in the items Mesh view Mesh quality To change the mesh the whole process can be repeated GiD allows also changes by editing the mesh dimensions and properties 2 1 6 4 Assign conditions to mesh nodes Now if needed it is possible to assign additional conditions or materials directly to finite elements of nodes Select Data Conditions as shown in Figure 2 24 For this we must select by mouse the node where condition should be applied It is however recommended to assign the material properties and boundary conditions on the geometric entities rather then on the mesh otherwise it is necessary to reassign such properties every time the mesh is regenerated NE Displacement bo Y Diplacement 0 0 Displacement 0 001
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