BasRock Trajec3D Manual
Contents
1. 8 Figure 3 Trajec3D Version 1 6 2 1 user IMera Cuad aria 9 Foures Steps to pud a CUSTOMS CCU sta e eE ace coa 10 Figure 5 Trajec3D trajectory strings loaded with GEMAD ooooccccocccnncccccncconcconnnnconcnonnnccnnonononncnncnnnnnncnnnnnnnos 11 Figure 6 Fall body snapshots indicating trajectory paths at different resolutiOnS ooocoooonncnncccnncccnncnnnns 12 Figure 7 Trajectory paths colour coding and resolution impact on the OUtCOME ceceeeeeeneeeeeeeeeeeeees 12 Figure 8 Custom fall body shape simplifications done by the physics engine cccccccooccnncccnnoccnncnononcconononnns 16 Figure 9 Extracting information from trajectory pathS ooccccccococncnncconnoncnnncnnnanennnnononnnnnnnnnnnnnnnnnonanncanenonnns 17 Rock Fall Modelling with Trajec3D 1 INTRODUCTION Falling rock can experience four types of motion along its path free fall rolling bouncing and sliding A typical rock fall consists of more than one of these motions during a single event No interaction takes place between the fall body and slope during free fall but interaction does take place for all other types of motion during which the rock may also fracture into smaller pieces During interaction of the fall body with the slope surface rolling bouncing and sliding the behavior is largely governed by the geometries and mechanical characteristics of the slope surface and fall body Basson 2012 Free fall Bouncing ys2. 4 5 2 Energy chart Provides three energy lines 1 Green line Rotational Energy due to the rotation of the fall body and a function of the angular velocity and moment of inertia 2 Purple line Translational Energy due to the linear movement of the fall body and a function of mass and velocity 3 Blue line Total Kinetic Energy Translational Energy Rotational Energy 4 5 3 mRL Provides the vertical displacement of the fall body with time The centre of the fall body is tracked and there will thus always be a discrepancy between the vertical displacement and the surface elevation of the topography 4 5 4 Grid Provides all the data for the selected trajectory path in a data grid Right click in the grid and select Copy to clipboard to copy all the information to the clipboard 17 Rock Fall Modelling with Trajec3D 4 5 9 Histogram The histogram divides the ditance between the highest and lowest fall body into equal intervals and counts the number of fall bodies in each bin The number of bins can be changed in the top right corner of the chart from 1 and 25 4 6 Physics material interactions Material properties are not assigned to each material individually but the physics interaction between two materials is specified As all fall bodies of an evaluation is assumed to have the same properties the differentiation between the materials is coloured on the topography Currently two materials can be assi
3. m gt f Sliding Figure 1 Types of motion during a rock fall Lo et al 2008 Although computer simulations are used for many reasons the most relevant to rock falls are 1 Visualise potential rock fall patterns 2 Quantify potential outcomes for example 1 in 5 rocks from a specific bench face will end up on a ramp Comparative and sensitivity studies with different variables Exposing surprise events overlooked by visual inspection Educational tool toy that opens the imagination to potential outcomes 2 OVERVIEW OF ROCK FALL MODELS Three approaches could be used to simulate rock falls lumped mass rigid body dynamics and discrete elements Each approach has advantages and disadvantages that are briefly discussed 2 1 Lumped mass models Lumped mass or stereo mechanical models represent falling bodies as point masses and ignore the fall object shape and size The fall body mass does also not affect the overall fall body trajectory but is only used to compute energy Lumped mass models can only represent sliding motion and mimics rotation with a zero friction angle Rock Fall Modelling with Trajec3D Two fictitious input parameters the normal and tangential coefficients of restitution are required for lumped mass models to compensate for the lack of physics in these simplified models In reality the coefficient of restitution depends on factors such as the incident angle frictional characteristics of the fall bo
4. press the Create fenches button after completion of each fence Build 13 Rock Fall Modelling with Trajec3D continuous fences by pressing the Shift button on the keyboard during building A rigth mouse button click in the scene cancels the action The button also functions as a toggle switch and turns green when fence building is active Create markers Pressing this button bring up a pop up form where the shape colour and size can be changed Markers Sphere Marker Cylinder Cone u Shape Cone down Colour Purple Diameter Height 7 Visible After pressing Accept to confirm the selections the markers are created at each clicking point until the Create markers button is pressed again or the right mouse button is pressed 2 Measuring tool After pressing this button select two points to measure The result is shown at the start of the measurement as the distance and dip angle between the points KN Sectioning tool The sectioning tool cuts away sections of the scene Define the cut away with two points and if done from left to right the closest part will be hidden Selecting any other function will unhide the hidden part or unhide by selecting the sectioning tool again and right clicking in the scene di 7 Create fall bodies on a regular grid The Rain button allows the creation of a regular grid of fall bodies across the full footprint of the triangulation belo
5. tab provides options for changing the global properties physics modes and interaction types Environment Simulation Engine Gravity m s2 Density t m3 Body rotation Body interaction Mouse collision Vertical paths 9 8 27 0 Disable Disable Disable Enable Enable Enable 18 Rock Fall Modelling with Trajec3D Gravity m s Gravitational acceleration with the sign indicating the vertical direction A negative number forces gravity downwards and is the default and a positive number will pull fall bodies vertically upwards This number will normally be left as the default value Density t m select the fall body density which determines the size of the fall body with the body weight Higher densities will result in smaller fall bodies Body rotation Rotates the fall body around the Z axis before release This is not often used but can be useful if the straight edge of a fall body needs to allign with a topography surface Body interaction Determines if fall bodies interact with one another with Disabled as the default Interaction between fall bodies could be usefull when tracking the accumulation of fall bodies in a small volume For example when useing Trajec3D to monitor water flows and an indication of the amount of accumulation at a particular location is required Mouse collision Determines where mouse cursor collisions will be registred during placement of fall bodies The default is Di
6. LES The parameters that influence rock fall behaviour in rigid body dynamics physics engines are the coefficient of restitution friction angles fall body size fall body shape and the topography surface 3 1 Coefficient of restitution Cr The elasticity or bounciness is defined by the coefficient of restitution a fractional value representing the ratio of speeds after and before impact taken along the line of impact A coefficient of restitution of 1 indicates a perfectly elastic collision with no loss in velocity and thus no loss in energy A value of O implies a perfectly plastic collision where all the velocity along the line of impact is absorbed If such a fall body impacts a surface at an angle the fall body will not be brought to rest but the velocity component along the line of impact will be absorbed Rock Fall Modelling with Trajec3D The velocity coefficient of restitution for an object bouncing from a stationary object is defined as where v is the scalar velocity of the fall body after impact and V is the scalar velocity of the fall body before impact Whe rocks are dropped from a known height onto a horizontal surface the COR can also be calculated with C H where h is the rebound height and H the drop height This is an easy way to determine CR values for different surfaces in the field Basson 2013 3 2 Friction angles Both a static and dynamic friction angles can be specified in rigid body dynamics p
7. SRMS Golden Rocks 2006 41st U S Symposium on Rock Mechanics 50 Years of Rock Mechanics Landmarks and Future Challenges Lo C M Lin M L and Lee W C 2008 Talus Deposition Pattern of Rockfall through Mechanical Model and Remote Sensing technology presentation Geophysical Research Abstracts Vol 10 5th EGU General Assembly 21
8. Trajec3D Manual BasRock Software for Geotechs Frans Basson 8 6 O be IO MOS x 0609 Pah Chart Delete Fence Marker Lengh Secion Ran Smooh Flip mae 2 Trajec3D Scene A Velocity Energy mRL_ Grid Energy kJ vs Time s 8 75 5584 8kJ 10 15 20 25 30 35 Time s Physics material interactions a Int00 intO1_ Into2_ New Material description Soft with high friction Coefficient of restitution CR 0 01 Environmental settings ES Friction angles Time interval between physics calculation updates s Trajectory path Static ij 4 lu j Mesh Distance 2 m Higher Lower A i gt A None Scale 1 ROTATION POINT Easting 59437 9 Northing 9505 6 mRL 1290 ia Trajec3D Beta contact Frans Basson at mail basrock com for support e ESO ee a 2 6 6 O ai JO mee Xx at 2 Pah oa Delera Fence Marker Lengh Secon Ran Smooh Fip Colour Help hoe a Trajec3D Scene Zz Ei Energy mRL Grid 8 75 5584 8KJ y 0 15 20 25 30 35 Time s Physics material interactions a intOO int int02 New Material description Soft with high friction Coefficient of restitution Environmental settings _ CA a l o 2 5 un Simulation Makers Friction angles gt Mass ton Time interval
9. between physics calculation updates s Trajectory path Static 45 Body mass 004 Ly E Real time Mesh Distance 2 m 2 gt 1000 Higher Lower A 7 a Dynamic 40 onay 5 a Stop time None Scale 1 ROTATION POINT Easting 59437 9 Northing 9505 6 mRL 1290 Version 1 April 2015 http basrock com http www facebook com basrock4u Rock Fall Modelling with Trajec3D Foreword This is a working document that will be expanded and adjusted in future Numerical modelling is not a static discipline and the knowledge relating to the subject in a constant state of flux The subject is also vast and impossible to cover in a single booklet The author incorporated only the essential knowledge required to equip engineers to assess simple rock fall incidents The target group for this guideline is site based geotechnical engineers with the purpose to provide an introductory manual to rockfall modelling with Trajec3D Only basic concepts are covered and further reading is recommended for engineers who want to pursue the subject in detail This guideline aims to provide a basic understanding of the principals involved in rock fall modelling show the working of Trajec3D and demonsirate potential ways to utilise Trajec3D modelling in a production environment Rock Fall Modelling with Trajec3D TABLE OF CONTENTS Ll INTRODUCTION siii 5 2 OVERVIEW OF ROCK FALL MODELS 0ccooccococcncccnccconcconcnonccon
10. cnonanas 5 2 1 LUmpbed mass Models ssie E a 5 22 FRIGIG DOG AYNAMICS acia 6 Zo WDIScCrele elemen luna E 6 3 ROCK PALL VARIA BEES iia Ss 6 3 1 Coefficient of restitution Cria aaa 6 Dic o O 7 3 3 FRAN Dody SiZ atico till ls iii 7 SA ooo lo AA o e anenceuracces nea ht assaeeasaevcue otevecurnscos nen does eucncnuseeasesen 7 39 DIODE HCOE yV ani iii nie 8 4 TRAJEC3D USER MANUAL Loccoocconcconccncconoconccnnnonononnnnanenanonnnnanenanos 8 Ast USE INGE AC Goa secre uncesceumee seo A 8 AZ A A 9 A loo Ae tent cunmesdeouvevenaimccr stand 10 A Side 1OOND al 15 49 Resu CIVAIUS sos tacceccn toes esa tecc a a ica pecans Gagan eieanecanteandenticamecaneonneaane 16 4 5 1 VOC ENa te criado id iacbcbas 17 4 5 2 ENCON C A e a aid 17 4 5 3 aA a esata Sees ete o ado 17 4 5 4 A peat EEE E ie tetera ttt Seatac nse E Vorsteces ian bee ia anne aes A A E E ta eee E T 17 4 5 5 tN UO CI ANA ct cold 18 4 6 Physics material Itaca aid 18 4 7 Information amp Environmental SettidgS oomcconncconncnnnnconnnnnncnonnncnanenanrnonnrnnarenanrnnanennans 18 4 7 1 MONA ia a ren em ee eee 18 4 7 2 ENVIO MEN le 18 4 7 3 SIMAO da iia 19 4 7 4 ENOIMCraai aaa a 20 REFERENCE Ono 21 Rock Fall Modelling with Trajec3D FIGURES Figure 1 Types of motion during a rock fall Lo et al 2008 o cccoconnnccconncncononcnnononcnnononcnnnonanonnonanennnnanons 5 Figure 2 Examples where slope geometry impacts on out of plane fall body trajectories
11. ctivate a tooltip with a short description of the functionality of that particular object 4 1 User interface The Trajec3D Version 1 6 2 1 user interface is shown and marked in Figure 3 1 User interface Graphics scene Top toolbar Side toolbar Result charts Material properties ao ot o e RN Information box Rock Fall Modelling with Trajec3D Each area is discussed in detail in the following sections 1 User interface gt be 3 2 ia Top toolbar Colour Help Result charts Traje I 7 120 0 5 10 15 20 25 30 35 Soft high friction Coefficient of restitution CR 0 01 i ras 7 Environmental settings icim angles Select chart Mass ton Time interval between physics calculations Trajectory path Static 45 _J Body mass 004 s 4 lag gt E Realtime Mesh Distance 2 w m Dynamic TR 10 4 a Posta E Stoptime None Scale 1 ue ROTATION POINT Easting 135 7 Northing 61 4 mRL 102 7 Figure 3 Trajec3D Version 1 6 2 1 user interface 4 2 Graphics scene The area displays the graphics and makes use of the Microsoft DirectX 9 graphics library set All interactions in the graphics scene are mouse driven where e Left mouse button press Rotate the objects in the scene by moving the mouse e Right mouse button press Cancel all selected actions and zoom towards or away from the objects when moving the mouse When the physics mode i
12. dy and slope contact and the collision point on a fall body shape with non spherical shape Curran et al 2006 2 2 Rigid body dynamics Rigid body dynamics modelling is a less sophisticated approach than discrete elements but still captures the essence of fall body behavior This approach uses the equations of motion and kinematics assumes an instantaneous period of contact and the contact region between colliding bodies are very small This method is fast enough for real time simulation of multiple fall bodies and even for probabilistic analysis Curran et al 2006 The input parameters for rigid body mechanics are few measureable and intuitive In addition to shape mass and velocity rigid body dynamic models only require the static and dynamic friction angles and elasticity of the contacting surfaces Rigid body dynamics models consider the fall body shape and volume and can solve for all the types of motion including rotation 2 3 Discrete element The discrete element method DEM code can accurately model rock slope interactions and even simulate breakup Curren et al 2006 but 1 Are time consuming to set up Require many input parameters with some not observable and difficult to estimate Require an expert user as the software is not user friendly Are reasonably expensive Could require high end hardware Oy ON a 2a ES Have slow computational speeds due to the extremely small time steps required 3 ROCK FALL VARIAB
13. e acts similar to a spinning wheel a Mathematical perfect square box shape This shape is useful for actual rock fall analysis but should only be used when the actual potential fall bodies are reasonably square This shape could start to topple and roll below the friction angle of the interaction surface which does not occur with flat shapes which will rather slide Mathematical perfect flat box shape This shape is very useful for actual rock fall analysis as fall bodies are often flat slabs that preferentially slide rather than roll a Mathematical perfect elongated box shape Use this shape if the actual fall bodies are flat and elongated Q Angular rough cylinder shape This could be a useful shape for near spherical fall bodies This shape tends to roll substantially further than flat fall bodies and will typically give very conservative results o Angular rough smartie shape This shape tends to continue further than the angulat flat cylinder shape as it rolls more easily over the rounded edge e Angular rough flat cylinder shape This could be a useful shape for actual rock fall analysis Multiple bodies for simultaneous release This option shows a form where the number of fall bodies of a particular type could be selected and the selected fall bodies are simultaneously released to create a large number of fall bodies 15 Rock Fall Modelling with Trajec3D 4 Custom fall body shape f
14. e trajectory paths as coloured cylinders The Distance value set the approximate distance between result captures with smaller values resulting in a higher resolution of captured results The Scale value scale the captured fall body mesh to make a very small fall body trajectory path more pronounced 4 7 4 Engine This tab hosts a few options that are seldom used and of little importance Environment Simulation Engine Anti aliasing Multithreading Digable Disable Enable Enable 20 Rock Fall Modelling with Trajec3D Anti aliasing is a smoothening filter to reduce the ragged effect from screen pixelation Anti aliasing is enabled by default and should not markedly impact performance on modern computers Multi threading could accellerate some simulations but could also cause numerical instability and is disabled by default REFERENCES Basson F R P 2012 Rigid body dynamics for rock fall trajectory simulation ARMA 12 267 46 US Rock Mechanics Association held in Chicago June 2012 Basson F R P 2013 Coefficient of restitution for rigid body dynamics modelling from on site experimental data Slope Stability 2013 International Symposium on Slope Stability in Open Pit Mining and Civil Engineering held in Brisbane September 2012 Curran J H and Hammah R E 2006 Keynote Lecture Seven Lessons of Geomechanics Software Development ARMA U
15. elp 0 60 a 20 60 PS ee Step 2 90 0 Empty scene Load the default pat shell Matt Build a custom slope Matl Load a custom slope TWM le Mati Load a senes of XA Y Z coordinate i Figure 4 Steps to buid a custom section 10 Rock Fall Modelling with Trajec3D E Physics interaction Material 2 Pressing this button opens a form where the second physics interaction material properties are defined The cut off angle is the only aspect not yet discussed and defines the polygon angle that differentiates the two interaction materials For example if the default angle of 20 is accepted e Polygons with a dip angle of greater than 20 will be assigned the Physics Interaction Material 1 properties defined in the Material properties section and coloured golden brown e Polygons with a dip angle smaller or equal to 20 will be assigned Physics Interaction Material 2 and coloured blue green teal Various save options Screenshot to clipboard Saves a screenshot of the graphics scene to the clipboard but only works when Trajec3D is displayed on the main computer screen When Trajec3D is running on multiple monitors and Trajec3D displayed on a secondary or tertiary monitor a Clipboard error message will be displayed Trajectory paths as DXF strings All trajectory paths will be saved as strings coloured on velocity similar to the output from the Path button see below These DXF files can be acc
16. f similar behaviour e Delete all bodies paths lines markers and fence Delete all fall bodies Hide all meshes of all paths Delete all measure lines with text Delete all markers and Delete all fences are all single actions that execute on the button press e Delete a single fall body Hide meshes of a single path Hide a single path mesh Delete a single measure line with text and Delete a single marker all require the following actions o Select the menu option o Move the mouse cursor over the object or object set such as a trajectory path to be hidden or deleted the object s will be highlighted o Press the Delete button on the keyboard If the delete button is held in all the object s the mouse cursor touches will be affected This is a usefull to quickly delete or hide a large number of objects un fm Create fenches The first time this button is pressed after a pit shell was loaded brings up a form with the physics interaction properties between the fall body and fence and the fence heigth and angle from vertical Catchment fence E Coefficient of Restitution Fench properties CR 001 Height 20 m Angle 1h Friction angles Static 65 When the button is pressed thereafter the properties are used and the form not shown again A single or multiple fenches could be build and it can be done as individual objects or as a continuous string of fences To build individual fences
17. gned in Trajec3D with the main material interaction called Mati and shown in golden brown and the second material Mat2 is shown as blue green teal When a triangulation is loaded it is always done as Mati The second material can then be defined based on the angle from horizontal as discussed in section 4 3 under Physics interaction Material 2 The logic behind this approach is that steep surfaces are assumed to be solid rock and flat surfaces the accumulation of rock fragments The steeper Mat1 material interaction thus typically has a higher Coeffient of Restitution than the softer Mat2 interaction The softer Mat2 will typically have a higher Friction Angle than the solid rock as the soft broken fragments will resist the ploughing movement with a friction angle far exceeding the intact friction angle as discussed in Section 3 2 4 7 Information amp Environmental settings The Information amp Environmental settings are at the bottom of the Trajec3D interface Information amp Environmental settings q a Environment Simulation Engine Gravity m s2 Density t m3 Body rotation Body interaction Mouse collision Vertical paths 9 8 v 27 y 0 e Disable Disable Disable Enable Enable Enable 4 7 1 Information The information box keeps record of actions that were taken during a session Most button presses will result in the addition of new lines to the information box 4 7 2 Environment The Environment
18. hysics engines The Static friction angle is only applicable when fall bodies are set to interact and a body that came to rest is impacted by another moving body In a typcial rock fall analysis where fall bodies are not interacting the Static friction angle has no importance and can be set to the same value as the dynamic friction angle Determining the dynamic friction angle for a rock fall is not trivial as the number is typically not the friction angle of the intact rock Imagine a large fall body ploughing through a catch berm covered with small broken fragments of rock The soft broken fragments will resist the ploughing movement with a friction angle far exceeding the intact friction angle This is important to consider during analysis as a low friction angle will allow sliding on the catch berm and the fall could then contue to following benches in the analysis 3 3 Fall body size Large blocks are not as easily caught by catch berms as small blocks The larger blocks tend to fall further and are less affected by the catch benches typically resulting in greater maximum velocities than the smaller blocks By comparison to the fall body size a catch berm is thus a smaller obstacle for a larger fall body 3 4 Fall body shape Rounded shapes fall further down a slope than angular bodies Flat and angular fall bodies are typically the easiest to arrest by catch benches as they tend to slide and do not easily topple and roll down slope
19. imulation accuracy or to the left to increase the number of calculations per second for a more accurate result Time interval between physics calculations 004 s 4 Real time Higher AAA lower ars 25 S sccuracy Default accuracy C Stop time In the screenshot above 0 04s is the time between consequtive culculations and 25 s thus the number of calculations per second By checking Real time the calculation rate will automatically adjust to provide a simulation close to actual time and useful to obtain an understanding of the time required for a particular rockfall event This option is not recommended for accurate analysis as the time between calculations could vary Checking Stop time will stop a simulation until the box is unticked This is useful to set up a scene with multiple types of fall bodies and then let them go simultabeously by unchecking the checkbox Trajectory path Trajectory path Mesh Distance 2 m None Scale 1 This frame encapsulates the parameters that impact on the resolution of capturing and displaying trajectory results Checking the Mesh radio button will result in capturing of fall body meshes along the trajectory path and None will not capture any fall body meshes but the results will still be captured To display the results when the fall body meshes were not captured press the Path button on the top toolbar to display the trajectorues as coloured cylinders see Section 4 3 Creat
20. rajectory paths as coloured cylinders This button changes the trajectory paths to cylinders coloured on the velocity between Om s blue and 25m s red A colour scale legend is not shown in Trajec3D and the Figure 7A could be used if a scale is required 7A Colour scale 7B Example result with Figure 6 trajectories shown as coloured cylinders nn E _ lt E gt 2 oO O v gt Figure 7 Trajectory paths colour coding and resolution impact on the outcome 12 Rock Fall Modelling with Trajec3D This action is irreversable so the fall body snapshots are lost after this selection is made and cannot be regained for this particular analysis a Ts Create charts of the selected trajectory path This button activates the chart mode where the mouse cursor changes to a cross the trajectory path below the cursor is highlighted and the information of the trajectory path is displayed in the Results Chart area see Figure 3 The specific value applicable to the segment directly below the cursor is displayed on the chart as a number and dynamically changed as the cursor moves across the path The button also functions as a toggle switch and turns green when the charts mode is active Delete selected or all entities This button allows the deletion of fall bodies paths measuirng lines markers and fenches The options are self explanatory and will not be individually covered The options can be divided into two groups o
21. rom a DXF file Any triangulated shape could be loaded as a DXF file and used as fall body The physics engine will simplify the triangulation to a concave shape see Figure 8 but the triangulation will be visually unchanged 8A Triangulation vs Physics body 8B Android Man as fall body in Trajec3D z ee VIVE HO pa Sn a IRMA Vy A MY t Ya Fiz E 1 TE tam If the fall body triangulation is Android Man The fall body is represented by the detail wireframe but white Trajec3D will simplify the physics shape to the physics engine does the calculations on the the convex blue translucent shape simplified convex shape shown to the left Figure 8 Custom fall body shape simplifications done by the physics engine A detail representation could be made of the fall body by taking multiple photographs from different angles and then creating a fall object with free software such as 123Catch http www 123dapp com catch This shape can then be loaded into Trajec3D and scaled by entering the appropriate density and fall body mass see the section on Environment seitings 4 5 Result charts The result charts area contains data charts and grids of selected trajectory paths When the Chart button is pressed and the mouse cursor moves across the trajectory paths the path underneath the cursor will be highlighted as shown in Figure 9 The information of the trajectory directly below the cursor is di
22. s Rounded volumetric shapes typically runs out substantially further than other shapes as they easily start to topple and roll down slopes The anticipated shape of fall bodies in a particular area should thus be carefully considered Rock Fall Modelling with Trajec3D 3 5 Slope geometry The slope geometry can have a huge impact on fall body trajectories as shown in Figures 2A and 2B Two dimensional rock fall models do not capture these impacts and care has to be taken to account for this variability when two dimensional analyses are performed 2A Out of plane bouncing 2B Out of plane rolling and sliding LAS AS Figure 2 Examples where slope geometry impacts on out of plane fall body trajectories 4 TRAJEC3D USER MANUAL Trajec3D was developed with a games graphics and physics engine which are used in commercial games but also applications The physics engine implements a deterministic solver that makes it suitable for real time physics simulations The physics interaction between materials is a function of the combined properties of the fall body and the impact surface and only three parameters are required coefficient of restitution static and dynamic friction angles As discussed in Section 3 the static friction angle is only applicable when fall bodies are set to interact and has no importance in a typcial rock fall analysis Keeping the mouse cursor stationary on any interface object button check box etc will a
23. s activated and the mouse cursor over a triangulation this button generates fall bodies close to the triangulation e Middle mouse wheel press Pan the scene across the screen when moving the mouse e Middle mouse wheel scroll Zoom towards and away from the objects e Left mouse button double click Centre the mouse on the selected point or centre the scene if clicking occurs in empty space e Moving over objects In some modes moving the mouse over objects wil provide information as discussion in later sections The vertical scroll bar to the right of the graphics display area makes the pit transparent to enable inspection of fall paths obscured by the pit triangulation Rock Fall Modelling with Trajec3D 4 3 Top toolbar The top toolbar accesses the main functionality within Trajec3D and each item is discussed separately Q Physics Interaction Material 1 Empty scene Reset the program and clear the scene Load the default pit shell Mat1 Load the pit shell automatically loaded when opening Trajec3D Build a custom slope Matt Build a slope triangulation from the design parameters and save as a TVM file Load a custom section CSV Extrude a comma delimited section to a triangulation with the required steps shown in Figure 4 Load a custom slopeT VM file Matt Load a previously build custom slope Load a DXF pit triangulation Matt Load a pit triangulation from a DXF file 0 60 File Edit Format View H
24. sabled which only creates new fall bodies when picking on the topography surface Selecting Enabled will create new fall bodies whe picking on the topography surface as well as other fall bodies Vertical paths The default is Enabled except when the Rain toggle is on see Section 4 3 under Create fall bodies on a regular grid This selection determines if perfectly vertical paths are recorded When a fall body bounces from a topography vertical paths will not occur but they do occur during the initial free fall when the Rain option is selected When Disabled the vertical lines do not obstruct the view and the redundant information does not consume memory 4 7 3 Simulation The Simulation tab provides options for changing the simulation parameters and recorded results Mass ton Time interval between physics calculations Trajectory path Body mass 004 s 4 j Feal time Mesh Distance m 10 z 25 ofS call Default oxic Stop time None Scale 1 Mass ton Body mass select the mass of the fall body in tonnes This value is combination with the Density under the Environment tab determine the volume size of the fall body 19 Rock Fall Modelling with Trajec3D Time interval between physics calculations This frame encapsulates the parameters that impact on the physics engine accuracy The sliding bar can be dragged to the right for quicker run times at the cost of s
25. splayed as text on the graph to the left This text changes as the cursor is moved across the trajectory path The interval distance between sample points for the graph can be changed in the Distance textbox of the Trajectory path frame of the Simulation tab as discussed in Section 4 7 under Environment 16 Rock Fall Modelling with Trajec3D Trajec3D Beta contact Frans Basson at PI com for support o O fee 2 6 O A 0 MO lt gt 9 Matt Start Pah Fence Marker Length Secon Rain Flip Colour Result charts A Trajec3D Scene Velocity Energy mRL Grid afo Velocity m s vs Time 0 012345678910 IntOO Material description Soft high friction Coefficient of restitution pan T7 Information amp Environmental settings g Enable charts Environment Simulation Markers Engine Fricti Select fall body a anges ConvexHullCylinder Mass ton Time interval between physics calculations Trajectory path Static 45 a oe Body mass 004 s 4 gt Fl Real time Mesh Distance 2 vm Dynamic an y Select fall body BoxS 10 X sa Higher Lower lt e oi jox Square Sens cones Baan Stop time None Scale 1 ue ROTATION POINT Easting 1906 9 Northing 1744 7 mRL 1093 5 Figure 9 Extracting information from trajectory paths 4 5 1 Velocity chart Provides the velocity graph of the selected path in m s
26. ummuated from different runs and simulataneously opened in GEM4D as show in Figure 5 me AY gy ee so gt s e e oS le AG mie yee r ll LA Figure 5 Trajec3D trajectory strings loaded with GEM4D All trajectory path information Trajecty information from all paths are saved as a comma delimited CSV file as shown below This allows manual manipulation of the data in Excel when required BER Time s Easting whee es mRL Vel m s LinEnergy kI RotEnergy kI 9 5 58 6 36 3 0 0 0 0 0 0 a Pda Ln un a o a 5 34 4 5 7 163 9 4 4 1 1 0 258 9 58 5 32 1 8 5 358 8 8 9 1 1 2 258 6 58 4 29 8 10 5 553 9 13 2 1 1 4 258 3 58 3 27 6 12 2 748 6 17 5 1 1 6 258 0 58 3 25 5 13 6 925 5 21 3 1 1 8 257 7 58 2 23 2 15 0 1121 2 25 5 1 1 9 257 3 58 1 20 7 16 4 1337 7 30 1 1 2 0 257 1 58 1 18 7 17 4 1511 0 33 8 1 2 2 256 8 58 0 16 6 18 4 1694 7 37 7 1 2 3 256 5 57 9 14 3 19 4 1889 2 41 8 11 Rock Fall Modelling with Trajec3D CS Start the physics engine This is the main button in Trajec3D and starts the physics engine and change the behaviour of the right mouse button from zoom to fall body creation To stop the creation of fall bodies press the Start button again or select any other function The button functions as a toggle switch and turns green when the physics engine is active a LULL a id Figure 6 Fall body snapshots indicating trajectory paths at different resolutions e Create t
27. w Different density grids can be created and the triangulation paths saved with Save Trajectory paths as DXF strings These files can then be loaded simultaneously with GEM4D to create surface flow patterns as shown in Figure 5 vw Flip polygons Flip the polygons to assist with data inspection The triangulation can also be made transparent with the slider bar to the right of the scene sur Change background colour 14 Rock Fall Modelling with Trajec3D The background colour can be changed to any colour in the available palette To change back to the default graded background press the Colour button and then press Cancel instead of OK or close the colour selection form with the top right red cross gt r e Help and About Options to check for program updates and activate the About screen If Decline is pressed on the About Form the program will exit 4 4 Side toolbar The toolbar to the left of the scene contans the different fall bodies that could be selected Q Mathematical perfect sphere shape This shape should not be used for actual rock fall analysis as a sphere will continue to roll on a flat surface This shape is useful for theorical analysis though as the behaviour of a bounce is predictable and only a function of the topography o Mathematical perfect flat cylinder shape This shape could be used for actual rock fall analysis but rolling could still be an issue where the shap
Download Pdf Manuals
Related Search