Form Selection Action / Object / Method Input Data Notes

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Form Selection Action / Object / Method Input Data Notes

APPENDIX B: Instructions to run PATRAN/ABAQUS: Part 1 (Year 2007/8) – (revised 28 Jan 2008) 1. INTRODUCTION This document provides detailed step-by-step instructions for completing the four parts of the analysis required for module 4D6 coursework. Before using these instructions, please read sections 1 to 3 of ‘PATRAN Beginner’s Guide’.

2. STARTING A PATRAN SESSION Login:... Log-in to the cluster timetabled for this lab. (Clusters 4 , 6 and 5B) Then click the RMB in any clear area and from the menu which appears choose the Open Terminal option. In the X-term window type slogin  substituting for from the list shown below depending on which bench you are at : for 4A : scimitar 4B : kukri 5B : tanto 6A : khopesh 6B : tachi Example if you on 4A type : slogin scimitar In the new window enter your Password. Check that the x-term prompt has the appropriate server name. This is to ensure the session loads are equally divided between the different servers. df -k /homes Make sure you have enough diskspace. You will need around 50000 Kb to run PATRAN. Your quota should have been increased to allow this, but if there are any problems, email [email protected].

export PATH=$PATH:./  Set the current directory to be included in the current path . You need to type this every time you login to run this lab. echo $PATH  Type this and check the PATH name has :./ (dot followed by forward slash) at the end. If not re-type the export above command again and repeat the echo command. start 4D6  Start the lab. This command first creates a working directory called pat4D6 and copies the necessary files and then starts the PATRAN program. This is the only command you need to use throughout. DO NOT USE the patran COMMAND for this labs. ALWAYS USE start 4D6. In the following pages under the heading Form Selection (First column) the following symbols have the following interpretation :

B1 ______Form______Selection Action / Object / Method Input Data Notes This represents Menu selection from the TOP line. (eg FILE, GROUP). This refers to forms below the menu level (eg. GEOMETRY, ELEMENTS). Click on this to open the form next to it. Click on it again to close the currently open form or click on of another form to close the current form.

WHEREVER THIS SYMBOL APPEARS FURTER USER ACTION IS REQUIRED (IN THE INSTRUCTIONS WHICH FOLLOW ).

NODE SIZE

CYCLE SHOW LABELS PLOT/ERASE FORM LABELS POINT SIZE

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B2 ______Form______Selection Action / Object / Method Input Data Notes 3. CREATE A NEW DATABASE File/New ... Change Template ... Create a new model database Select: 4D6_template.db ... from the Database Template list OK ... in the Database Template form New Database Name: quake ... in the New Database form OK ... in the New Database form Approx. Max Model Dimension: 60 ... in the New Model Preferences form Analysis code: ABAQUS Analysis type: Structural OK ... in New Model Preferences form

4. CREATE GEOMETRY OF STRUCTURE This section creates the geometry of your structure — the nodes and elements used by the finite element analysis will be created later by PATRAN. Cycle Show Labels First click on the Cycle Show Labels Icon which will display the Point labels as these are created. Note : It is important to follow the instructions given below precisely and check the resulting geometry at every stage to make sure that any mistakes made are corrected before moving to the next stage. Main reason for errors (a) incorrect choice of options. (b) Incorrect entry of data. (c) Failing to unset AUTO EXECUTE where indicated (d) Duplicate entities (points/curves). (d) could be a result of (c). This is when PATRAN puts up a message saying that Do you want to Create a Duplicate Entity. This should act as a warning to indicate that the task has already been carried out. Choose the option NO and check. Any mistakes which remains undetected at the end of section 4 will give wrong results at a later stage. If this happens then you will have to re-do the labs from the beginning. Therefore take your time and carry out each step only when you have understood the action and the result of that step (From step 4.1 to 4.10). The Entity (Point/Curve) count in the Create form always refers to the NEXT entity to be created. So the last entity created would be 1 less than this number. When you start, this will display 1. (SET . Some of the useful icons are shown on the right of this. UNDO icon is the most ) the t useful at the early stages. Also useful are the Repaint and Clear icons. . . While inputting the Geometry the AutoExecute button has to be unset.where Repaint Clear STOP UNDO P Point indicated. . In order to be able to tell set and unset positions apart both positions are shown on the right. Node . When selecting entities from the viewport (Points/ Curves) the select menu ON (SET) /Picking Filter, (consisting of a set of icons) will pop up next to the form. These icons act as a filter and it is important to choose the correct icon when making selections. If the program is not recognizing the selection you are making then check the current choice of icon on the select menu. 3

B3 ______Form______Selection Action / Object / Method Input Data Notes

OFF (UNSET) Pickiing Filter n.b. When you are using PATRAN, the Backspace key may not work In that case try using the delete key instead. 4.1 CHANGE VIEWPORT BACKGROUND COLOR Viewport/Modify… Background Color Click on the Blue and change it to Black Apply, Cancel Click on these buttons in turn. 4.2 CREATE THE POINTS at SUPPORT Geometry Create / Point / XYZ Point Co-ordinates List: [0 0 0] Create first point at ground level Apply Refer to Fig. 4 in Page 5 of handout. Point Co-ordinates List: [5.6 0 0] Create second point at ground level Apply Calculate the co-ordinates from Fig.4

Continue to create all 5 points at ground level If you make a mistake then click on the UNDO icon. This will undo the last action. 4.3 COPY THESE POINTS TO FIRST FLOOR LEVEL Geometry Transform / Point / Translate Translation Vector Change the Action from Create toTransform Direction Vector: <0 3.65 0> Translate these points by 3.65m in y-direction. Repeat Count: 1 Do this once for the first storey. . Auto Execute Make sure this is UNSET. See previous page to tell the set and unset positions apart. Point List: Point 1:5 Click on Point List box, then draw a rectangle Apply around the Points 1:5.

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B4 ______Form______Selection Action / Object / Method Input Data Notes If heartbeat is pulsating Red continuously while you are trying to create the geometry and it is also taking too long, then try click and drag the MMB (Middle Mouse Button) in the viewport area. This should turn the heartbeat to Green. If this does not happen ask for help from a Demonstrator. . 4.4 CREATE THE CURVES AT FIRST FLOOR LEVEL Geometry Create / Curve / Point Auto Execute Check and make sure this is UNSET . Pickiing Filter: Point icon Click on the ‘point’ icon in the tool bar Starting Point List: Point 6 Click on the Starting Point List Box and And then click on point 6. Ending Point List: Point 7 Click on the Ending Point List box and Apply then click on point 7. Then APPLY. Starting Point List: Point 7 Click on point 7. Follow the above procedure. Ending Point List: Point 8 Click on point 8. Apply Continue with 8 & 9 and 9 & 10. Continue to create the 4 horizontal beams, which form the first storey (4 in total) Curves 1 to 4. Confirm this.

4.5 COPY THE CURVES TO THE OTHER 3 LEVELS Geometry Transform / Curve/ Translate Translation Vector: <0 3.65 0> Copy the 4 horizontal curves (1-4) 3.65m in the y-direction Auto Execute Make sure this is UNSET. Repeat Count: 3 Repeat for the remaining storeys. Curve List: Curve 1:4 Click on Curve List box, then draw a rectangle Apply around curves 1–4 in the input box.

This should create all the horizontal beams (12 in total) Curves 5 to 16. Confirm this.

4.6 CREATE THE CURVES FORMING THE FIRST COLUMN

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B5 ______Form______Selection Action / Object / Method Input Data Notes Geometry Create / Curve / Point Auto Execute Make sure this is still UNSET Pickiing Filter: Point icon Click on the ‘point’ icon in the tool bar Starting Point List: Point 1 Click on point 1. % Ending Point List: Point 6 Click on point 6. Apply Creates curve 17 Starting Point List: Point 6 Click on point 6. Ending Point List: Point 11 Click on point 11. Apply Creates curve 18 Starting Point List: Point 11 Click on point 11. Ending Point List: Point 16 Click on point 16. Apply Creates curve 19. Starting Point List: Point 16 Click on point 16. Ending Point List: Point 21 Click on point 21. Apply Creates curve 20 Create the curves which form the first column (4 in total). Curves 17 to 20. Check these numbers.

% When it says click on a point it means click on the marker for the point. This is a circle which is slightly to the left and below the label. This marker can be made visible by clicking on the icon (point size, 3rd from right on the icons in the main window). It is also the 3rd icon shown in Page B9. This marker also becomes visible when the cursor is over it.

4.7 COPY THE FRST COLUMN INTO THE SECOND COLUMN Geometry Transform / Curve/ Translate Translation Vector Translate these 4 curves Direction Vector: <5.6 0 0> by 5.6 m in x-direction Repeat Count: 1 Do this once to create the second column. Auto Execute Click on this to UNSET it. Curve List: Curve 17:20  Click on Curve List box, then on curve 17 and then HOLD DOWN the SHIFT key

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B6 ______Form______Selection Action / Object / Method Input Data Notes and click on curves 18 to 20. Apply Then Click on APPLY. This should create all the curves in second column(4 in total). Curves 21 to 24. If you make a mistake then click on the UNDO icon. This will undo the last action. Check these. 4.8 FROM THE SECOND COLUMN. Geometry Transform / Curve/ Translate Translation Vector Copy for the remaining columns Direction Vector: <12.3 0 0> Translate the 4 curves by12.3 m in x-direction Repeat Count: 3 repeated thrice for the remaining columns. Auto Execute Make sure this is still UNSET . Curve List: Curve 21:24  Click on Curve List box, then on curve 21 and then HOLD DOWN the SHIFT key and click on curves 22 to 24. Apply Then Click on APPLY This should create all the remaining beams in columns(12 in total). Curves 25 to 36. Check and confirm these.

4.9 DELETE THE CURVES NOT REQUIRED Geometry Delete / Curve Curve List: Curve 13 20 Click on Curve List box, then HOLD DOWN the SHIFT key and click on curves 13 and 20. Apply Delete the extra curves not required. 4.10 DELETE THE POINT NOT REQUIRED (IF THIS POINT DID NOT GET DELETED IN THE PREVIOUS , THEN PROCEED, OTHERWISE SKTP) Geometry Delete / Point Point List: Point 21 Place cursor in input box. Click on point 21.

Apply Delete the extra point not required. Check the Points and Curves numbers match the ones shown in Figure 1.1 Only then proceed. NB : If in doubt check with a demonstrator. Any errors detected at this stage can be corrected easily. Also avoids later re-doing the labs from the beginning.

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B7 ______Form______Selection Action / Object / Method Input Data Notes 5A CREATE THE BOUNDARY CONDITIONS Loads/BCs Modify / Displacement / Nodal Current Load Case: xxx If xxx is not static loading then click on it Existing Load Cases: static loading and select it from the existing list. OK ... in the Change Current Load Case form Select Set to Modify: fixed Click on this to select it. Modify Application Region ...... in the Loads/Boundary Conditions form Select : Geometry Pickiing Filter: Point icon Click on the ‘point’ (2nd ) icon in the tool bar Select Geometry Entities: Point 2 Click on point 2 Add . .. in the Select Application Regions form Select Geometry Entities: Point 5 HOLD DOWN the SHIFT key for Add making multiple selection. OK ... in the Select Application Regions form Apply  ... in the Loads/Boundary Conditions form Select Set to Modify: pinned Select pinned boundary condition Modify Application Region ...... in the Loads/Boundary Conditions form

Select the remaining points at ground level (1,3 and 4) and repeat the above procedure. These should then appear in the Application Region box, as above OK ... in the Select Application Regions form Apply  ... in the Loads/Boundary Conditions form

 The Blue cones should be displayed pointing to the directions which are fixed along with labels of variables fixed. 1 & 2 for pinned and 1, 2 & 6 for fixed. If these icons are not displayed then try clicking on the Apply button again. … Note :nnbb` If If the APPLY or any box referred to in the script cannot be seen in the form, the form needs extending. Click the LMB on the Top RHS corner and when the cursor changes into the icon shown drag it in the . vertical direction and then release it. Repeat until APPLy is visible.

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B8 ______Form______Selection Action / Object / Method Input Data Notes 5B CREATE THE LOADS Loads/BCs Modify / Force / Nodal Current load case: : xxx If xxx is not static loading then click on it Existing Load Cases: static loading and select it from the existing list. OK ... in the Change Current Load Case form Select Set to Modify: static load floor 1 Apply a force to the first floor Modify Data ... Click on this. Force < F1 F2 F3 >: < w1, 0, 0> Where w1 is the static equivalent load in to be applied to the first floor OK ... in the Input Data form Modify Application Region ... Pickiing Filter: Point icon Click on the ‘point’ icon in the tool bar Select Geometry Entities: Point x Click on point x, x is the point where the load is applied (first floor of lift shaft, RHS end). Add Click on this. OK ... in the Select Application Regions form Apply ... in the Loads/Boundary Conditions form

Add the appropriate static loads to all four floors, remembering to click on Apply before continuing with the next load. Yellow arrows would be displayed indicating the ______direction of the loading along with the magnitude of the load applied. Repeat for all 4. 6. DEFINE PROPERTIES OF ELEMENTS Properties Modify / 1D / Beam in XY Plane Select Prop. Set to Modify: beam_A Define which curves are beams of type A OK ... in the Input Properties form (properties are pre-defined) Select Application Region Click on this. Click in the Select Members input field Refer to Figure 4 in Page 5 of the handout Pickiing Filter: Select curve element icon to get the curves for this category. Select Members: Curve x y Click on the first curve and then HOLD DOWN the SHIFT key and click on Add other curves one at a time. This allows for Apply multiple selection to be made. No visible effect when this is assigned except for message in the PATRAN message window. Assign properties for every beam and column, remembering to always click on Apply ______before continuing with the next beam or column type until the last column K. 9

B9 ______Form______Selection Action / Object / Method Input Data Notes 7. CREATE FINITE ELEMENTS FROM BEAM GEOMETRY Elements Create / Mesh Seed / Uniform Number: 5 Assign 5 mesh seeds to each beam or column ______Curve List: Curve 1:12 14:19 21:36 Draw a box around the entire model Create / Mesh / Curve Element Topology: Bar 2 Choose standard beam elements Curve List: Curve 1:12 14:19 21:36 Draw a box around the entire model. Apply This generates the mesh. ______Node 205 Element 171 is displayed Equivalence / All / Tolerance Cube Apply Connect all the beam elements together

______Message in the PATRAN window : Geometric equivalencing complete. 44 nodes deleted. Optimize / Nodes / Cuthill-McKee Minimization Criterion: RMS Wavefront Optimize node numbering Apply OK ... in the Bandwidth Optimization Parameters ______dialogue box. 8.A IMPROVE DISPLAY OF MODEL Click on the Reset Graphics icon for cleaning up the the display. Display/Entity Color/Label/Render Hide all Entity Labels Get rid of superfluous information Curve: Label Replace Curve labels. Node: Label Replace Node labels. Apply Curve labels are in Yellow and Node labels are Cancel in Red. ______8B. CHECK THE FE MODEL Elements Show/ Node / Location Total in Model : 160 Check that the last ID is also 160

Show/ Element/ Attributes Total in Model : 170 Check that the last ID is also 170 Check that the node number of the top of the RHS column is 1 . Also check that the nodes at the support points 1 to 5 have the numbers 160, 123, 95, 63 and 31 respectively. If not DO NOT PROCEED until finding the mistakes and making corrections. The Finite Element Mesh with Node numbers is shown in Figure 1.2. It is possible that these node numbers could be different even though no mistakes may have been made. In that case note down the nodes at ground level on the Figure in page E1. Use the corressponding numbers instead of the above in appendix E. For now carry on with the next section. ______

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B10 ______Form______Selection Action / Object / Method Input Data Notes 8C. CHECK THE MODEL PROPERTES Display/Entity Color/Label/Render Hide all Entity Labels Get rid of superfluous informa Apply, Cancel Properties Show Existing Properties: Material name Select this. Display Method : Scalar Plot Apply This will display the colours for each property Viewing/Scale Factors… Model X : 1.2 This will re-scale it to show Model Y : 1.5 the labels clearly. ______Apply, Cancel Click on Apply and then on Cancel 8D. CHECK THE MODEL PROPERTES Utilities/Display… Property/Material Names… Select Element : Elm 1:170 Draw a box around the mesh. . Apply Click on APPLY. This will display the curves in colour ______Reset Graphics, Cancel Click on Reset Graphics and then CANCEL Properties Show Existing Property: Property Set Name Select this. Display Method : Table This gives a table to check that the curves ______Apply are assigned the correct properties. Viewing/Scale Factors… Model X : 1.0 Reset these to original values Model Y : 1.0 Apply ______8E. CHECK THE FINITE ELEMENT MESH

Click on the left most icon (Plot/Erase Form) shown and in the form, which appears, click on the ERASE button under Geometry(Posted Entities) Properties Show Existing Properties: Material name Select this. Display Method : Scalar Plot Fringe Attributes… Click on this. Element Shrinking factor : 0.5 Set this value using the slider. OK Apply This will display the f.e.mesh to be checked.. Elements will be shown shrunken. Now restore the view by resetting the shrink factor and click on the Plot/Erase icon and click on PLOT under the Geometry heading. 11

B11 ______Form______Selection Action / Object / Method Input Data Notes 9. DO STATIC ANALYSIS Analysis Analyze / Entire Model / Full Run Available Jobs: static_analysis Apply [The jobname (static_analysis) is already defined in the database. Do you wish to overwrite?]: Yes The viewport will be closed and the message Generating input for ABAQUS is displayed in a separate window. The ABAQUS job starts to run (in the background). The viewport should be back in display. Now move the viewport aside and look in the xterm window from which PATRAN was started. Look for the message nohup : appending output to `nohup.out` in that window. In the absence of any other error message this would in general means that the analysis was successful (continue with next section). However in case of errors the following message may appear in the same window Error detected … Aborting AbaqusExecute ______( In case of error locate and correct it. Look in the file nohup.out and static_analysis.dat for clues. Then skip to Step 15 & 16). 10. GET RESULTS Analysis Read Results/Result Entities/Attach Job Name: static_analysis Select Job Select Results File ... Selected Results File: static_analysis.odb Click on ‘static_analysis.odb’ in Available Files list box. If this file is not in the Available Files list your analysis had an error and didn’t run. See 15, below OK ... in Select File Apply ... in Analysis form ______Wait until green light (approx. 1 minute) 11. VIEW DEFORMED SHAPE Results Create/Quick Plot Select Result Cases: step 1,A1 Frame 1… Choose results just obtained Select Deformation Result: Spatial Displacements, U Choose displacements for plot n.b. do not select a Fringe Result, as they make the plot difficult to interpret. You can always clean up the plot with the broom icon ______Apply Plot deformed shape 12

B12 ______Form______Selection Action / Object / Method Input Data Notes 12. HARD COPY OF PLOT File / Print ... Current Viewport Available Printers: DPO Postscript Printer Apply Send plot to ljmr1 ______Cancel Remove Print window 13. READ OUTPUT Click on a free xterm window This step performed outside PATRAN. emacs static_analysis.dat &  View contents of Abaqus output file The results are at the end of the file. The node at the top of the lift shaft is usually Node 1, but you can check this as the node numbers are plotted in ______Red by PATRAN. 14. EXIT FROM PATRAN ______File / Quit In case this is the end of session then Quit. Otherwise ignore this and continue with the next step (step 17) 15. IF YOUR ANALYSIS HAD AN ERROR Try looking at the following files using emacs to track down the error:

Use one of the other xterm Type emacs& and choose File/Open. make sure that the current directory is pat4D6. nohup.out This should tell you which file (a) dat (b) msg file the error occurred. After viewing this file can be deleted by typing rm nohup.out. It will be re-created. static_analysis.msg.0? The latest file in this series (type ls in xterm window to see a list of files) will contain the steps taken by PATRAN to prepare the ABAQUS job

static_analysis.dat (a) This is the ABAQUS printed output file. This will list all the errors in the input data. static_analysis.msg (b) This file contains messages from ABAQUS about the analysis and run time errors.

If there are no errors in the geometry then the following are some of the common errors : (1) Boundary conditions and Loading not correctly specified. Repeat Steps 5A and 5B. (2) some of the curves had not been assigned properties. Identify the curves using Steps 8C/D/E.. Repeat Step 6 for the curves missing properties. (3) Mesh created is incorrect. Delete the FE Mesh. Using The Elements Form. Action/Object/Type:Delete/Mesh/Curve. Select all the curves. Redo Step 7. After making the necessary corrections repeat the Step 9. 13

B13 ______Form______Selection Action / Object / Method Input Data Notes 16 .DELETE THE ATTACHMENT TO THE OUTPUT DATABASE (CARRY OUT THIS STEP IF NECESSARY $} Analysis Delete / Result Attachment Existing Files: static_analysis.odb Select the file if it is listed. When you have to Apply re-run an analysis due to errors you need to first delete the attachment to the results file. If the file is not listed then skip this step.

$ This step is redundant with the latest version of PATRAN (Version 2005 R2). Howeverincluded in case of older versions of PATRAN * TROUBLESHOOTING NOTES o PATRAN session crashing This can happen for any number of reasons.In general except for the data you were working on when the crash occurred, data is rarely lost from the database. One possible reason for a crash is running out of disk space. Check your disk quota before starting PATRAN again. Restart PATRAN and choose File /Open and select the quake.db and continue. o PATRAN session becoming a runaway process O If the heartbeat pulsates Red continuously and if the viewport is visible then hold and drag MMB in the viewport. This might restore the heartbeat to Green. Then the database is usable, Proceed with the next step. O The absence of the viewport could indicate a problem. Check its CPU usage by typing top in a separate x-term window. Check the process p3 against your user-ID. If this is more than 90% then this would confirm it is a looping process. Wait a few minutes to make sure that it is not busy doing computation. Check the time the files were created. If files for the current analysis are not being updated this probably confirms the runaway theory. Ask a demonstrator for confirmation before proceeding with the next step.

Note the process-ID and kill it using kill -9 . Type q to quit from top. Resume the session by typing start 4D6 and when PATRAN has started re-open the Database again. If instead of getting the Green light it is continuous Red then kill the process again. That database is now unusable. Follow the procedure below : o How to recover an unusable database (a) Importing it into a new database after changing the template to 4D6_template. (b) Rename the unusable db and then try rebuilding the database using the journal file. (a) Type start 4D6 again and this time create a new database and add a number after the name example quake1 and change the template to 4D6_template and then choose File/Import and set source : MSc PATRAN DB. Choose the Old unuable database from the list of PATRAN databases. Then click on APPLY. The database should have all the data the previous database had. Continue using the new database.

______(b) Type : mv quake.db quake.db.err Type Start 4D6 . Seledt File/Rebuild… and select the quake.db.jou APPLY

B5 APPENDIX C: Instructions to run PATRAN/ABAQUS: Part 2(a)

______Form______Selection Action / Object / Method Input Data Notes 17. RELOAD DATABASE Skip this if continuing from previous section and the database is already open. File / Open ... Existing Database Name: quake.db Click on ‘quake.db’ in Database List ______OK ... in the Open Database form 18. CALCULATE MODES OF STRUCTURE Analysis Analyze / Entire Model / Full Run Available Jobs: eigenvalue_analysis Apply [The jobname (eigenvalue_analysis) is already defined in the database. Do you wish to overwrite]: Yes The viewport will be closed and the message Generating input for ABAQUS is displayed in a separate window. ______Refer to section 9 to remind what happens and what to do in case of errors. 19. GET RESULTS Analysis Read Results/Result Entities/Attach Job Name: eigenvalue_analysis Select Job Select Results File ... Selected Results File: eigenvalue_analysis.odb If ‘eigenvalue_analysis.odb’ isn’t in the right hand column, ABAQUS may not have completed its analysis. Wait a short while, thenclickon Filter. If ‘eigenvalue_analysis. odb’ still doesn't appear, your analysis had an error didn’t run. OK Apply ... in Analysis form ______Wait until green light (approx. 2 mins).

C1 ______Form______Selection Action / Object / Method Input Data Notes 20. PLOT MODE SHAPES Results Create/Quick Plot Select Result Cases: Step 1, Freq=1.7571, Md 1 Choose first (or other) mode Select Deformation Result: Spatial displacement, U Choose to show displacements ______Apply Plot mode. 21. HARD COPY PLOT File / Print ... Current Viewport Available Printers: DPO Postscript Printer In general to print it on ljmr1 one would click on Apply. However to reduce the the number of printouts ABAQUS/Viewer will be used instead. ______Cancel Remove Print window 22. EXIT FROM PATRAN File / Quit If this is the end of the timetabled session then Quit. ______Read the instructions given in a separate sheet to start up ABAQUS/Viewer and plot the mode shapes 23. READ OUTPUT Click on xterm window This step performed outside Patran emacs eigenvalue_analysis.dat &  View contents of Abaqus output file.

C2 APPENDIX D: Instructions to run PATRAN/ABAQUS: Part 2(b)

______Form______Selection Action / Object / Method Input Data Notes 24. RELOAD DATABASE File / Open Database ... Existing Database Name: quake.db Click on ‘quake.db’ in Database List ______OK ... in the Open Database form 25. CALCULATE RESPONSE TO THE EARTHQUAKE Analysis Analyze / Entire Model / Analysis Deck $ Method : Analysis Deck Change this Job Name : transient_analysis Choose the transient-analysis Direct Text Input ... *AMPLITUDE, VALUE=ABSOLUTE, TIME=STEP TIME, INPUT=QUAKE.AMP, NAME=EQ  Type this in the Additional Model Definition form as a SINGLE line. All in UPPER CASE and press the RETURN key at the end. This points ABAQUS to the earthquake file. Apply ... In the Additional Model Definition form Step Creation ... Available Job Step: modal transient Click on this. Solution Parameters... Delta-T: 0.01 Make sure the solution will be suitable for Time Duration of Step: 7.0 the problem Define Damping ... Lower: 1 Apply 5% damping to the analysis Upper: 10 Coeff: 0.05 OK ... in the Damping Table form OK ... in the Solution Parameters form Select Load Cases ... transient Select this if it is not highlighted. OK ... in the Select Loadcases form

D1 ______Form______Selection Action / Object / Method Input Data Notes Output Requests ... Increment between outputs: 5 Displacements ON Make sure the output file isn't too big Everything else OFF OK ... in the Output Requests form Direct Text Input ... *BASE MOTION, AMPLITUDE=EQ, DOF=1, SCALE=9.81  Type this in the Additional History Definition form as a SINGLE line. All in UPPER CASE and press the RETURN key at the end. This is to tell ABAQUS to apply the earthquake to the base OK ... in the Additional History Definition form Apply ... in the Step Create form [The stepname (modal transient) is already defined in the database. Do you wish to overwrite]: Yes

Cancel Step Selection… .. in the Step Select form Selected Job Step: eigenvalue (pe-modal ) Make sure these two appear modal transient in the order shown. Apply ... in the Analysis form

[The jobname (transient_analysis) is already defined in the database. Do you wish to overwrite]: Yes

$ Due to incompatibility between the ABAQUS and PATRAN the input file created for this analysis has to be edited before The analysis could be run. This process has been automated. To edit the input file and run this analysis you need to enter a command in the PATRAN command window. PATRAN command window (this is the last line in the main PATRAN form ie below the Message/History window which is below the Tool Bar (Icons)).

First click the left mouse button on the command line to indicate input and then type run_trans()  After typing run_trans() make sure to press the RETURN key. This will edit the input file and submit the analysis.

Move the PATRAN viewport aside and look at the comments which appear in the x-term window from which PATRAN was started. Messages will appear about progress of the ABAQUS job. This job requires a lot of processing, and ABAQUS may take a few minutes to finish its analysis. While the analysis ______Is running PATRAN heartbeat will be Blue. When this ______turns Green the analysis is complete. Proceed with the next step.

D2 ______Form______Selection Action / Object / Method Input Data Notes 26. GET RESULTS Analysis Read Results/Result Entities/Attach Job Name: transient_analysis Select Job Select Results File ... Selected Results File: transient_analysis.odb OK Apply ... in Analysis form Wait until green light (approx. 3 mins). 27. PLOT DEFORMATION RESPONSE This section will plot the displacement of the top of the lift shaft against time during the earthquake. Results Create/Graph/Y vs X Select Result Case(s): Step-2, 0 of 141 subcases Choose the transient analysis to open the Select Results Case(s) form Select Result Case(s): Step-2, 141 subcases … in the Select Results Case(s) form Filter Method: All Choose all of the results Filter Display all 141 increments Apply Close … in the Select Results Case(s) form Select Result Cases: Step-2, 141 of 141 subcases This change is made automatically --but make sure that it is highlighted. Y: Result Plot displacement on the Y-axis Select Y result: Spatial Displacements, U Quantity: X Component Plot time on the X-axis X: Global variable variable: Total Time Change this to Total Time. Target Entities Click on the 2nd icon in the row Select Nodes: Node 1 Plot the displacement of node 1 Display Attributes Click on the 3rd icon in the row X-axis label: Time (second) Y-axis label: Node 1, x displacement Labels for the graph Append Curve in XYWindow ______Apply

D2 ______Form______Selection Action / Object / Method Input Data Notes 28A. HARD COPY OF PLOT File / Print ... Current XY Window Available Printers: DPO Postscript Printer n.b. ensure you are not plotting Current Viewport Apply Send plot to ljmr1 Cancel Remove Print window ______28B. WRITING XYPLOT RESULTS TO AN ASCII FILE XYPlot Modify/Curve Existing Curve(s): Default_Graph 30 Data From Keyboard… Click on this Data Type: ◊ XY pairs Write XYData to File In Curve Data Keyboard form Apply Write to File:nospring Enter this file name OK In write curve Data form ______29. EXIT FROM PATRAN File / Quit ______

Note : In case of errors if your are repeating the analysis always check whether the Direct Input text in Section 25 ( 2 places) is still in place . PATRAN has the tendency of unsetting these and this will avoid having to re-run the analysis un-necessarily.

S.D. Guest January 19, 1999 MODIFIED JANUARY 2008 ` S.P.G.MADABHUSI

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D1

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