linear static analysis of a simply-supported stiffened...

WORKSHOP 15

Linear Static Analysis of a Simply-Supported

Stiffened Plate

MSC.Nastran 105 Exercise Workbook 15-1

Objectives:

■ Create a geometric representation of a stiffened plate.

■ Use the geometry model to define a MSC.Nastran analysis model comprised of CQUAD4 & CBAR elements.

■ Prepare a MSC.Nastran input file for a Linear Static analysis.

■ Visualize analysis results.

■ Understand the differences in PSHELL and PSHEAR.

15-2 MSC.Nastran 105 Exercise Workbook

WORKSHOP 15 Stiffened Plate (Sol 101)


Model Description:Below is a finite element representation of the stiffened plate shownon page 15-1. The plate is 0.2 inches thick; therefore, thin-shell theoryapplies. I-beam stiffeners are mounted as shown. The structure issimply supported at eight specified locations and a uniform pressureof 2.0 psi is applied to the surface of the plate.

When MSC.Patran creates a 2D Shell for a plate, a PSHELL card iscreated in MSC.Nastran with 3 MIDs. The first MID is the materialused to resist membrane (in plane) forces. The second MID is thematerial used to resist bending forces (moments). The third MID isthe material used to resist transverse shear (normal) forces on theelements. If any of these three materials are not supplied toMSC.Nastran, the solver then does not allow that element to take anyforces in the corresponding directions. For the first example, we willcreate a 2D Shell (PSHELL with all 3 MIDs given as same material).We will look at the maximum forces and stresses in the bars and quadelements, and also look at the maximum displacement.

Hint: Because the centroidal axes of the stiffeners do not coincidewith the mid-plane of the plate, you will need to account for this whenyou define the element properties for the stiffeners.

Figure 15.1- Dimensions and Specifications

a a

b

b

0.1

0.15

2.0

Stiffener

2.0 psi

50.0

60.0

1.0

A

A

View A-A

10.0

YZ

X

F E

C D

ze

ye


Table 5.1 - Material Properties

Elastic Modulus: 10E6 psiPoisson Ratio: 0.3Density: 0.101 lbs/in3

Plate Thickness: 0.2 inBar cross sectional area: 0.47 in2

Iaa: 0.2982 in4

Ibb: 0.0251 in4

J: 0.0028 in4



Suggested Exercise Steps:

■ Open a new database.

■ Define a geometric representation of the stiffened plate using a surface.

■ Define an analysis model by meshing the geometry model with shell (CQUAD4) and bar (CBAR) elements.

■ Define material (MAT1) and element properties (PSHELL and PBAR).

■ Verify XY-orientation and offset vectors for the bar elements.

■ Define simply-supported boundary constraints (SPC1) and apply a uniform pressure load to the plate (PLOAD2/PLOAD4).

■ Use the load and boundary condition sets to define a loadcase (SUBCASE).

■ Prepare the model for a Linear Static analysis (SOL 101 and PARAMs).

■ Generate and submit input file for MSC.Nastran.

■ Post-process results.


Exercise Procedure:1. Users who are not utilizing MSC.Patran for generating an input file

should go to Step 13, otherwise, proceed to Step 2.

2. Create a new database called lesson15.db.

In the New Model Preference form set the following:

3. Create a 10 x 50 inch surface.

4. Create the other five sections of the plate by transforming Surface 1.

File/New...

New Database Name: lesson15

OK

Tolerance: ◆ Default

Analysis Code: MSC/NASTRAN

Analysis Type: Structural

OK

◆ Geometry

Action: Create

Object: Surface

Method: XYZ

Vector Coordinates List: < 10 50 0 >

Apply

◆ Geometry

Action: Transform

Object: Surface

Method: Translate

Translation Vector: < 10 0 0 >

Repeat Count: 5



5. Activate the entity labels by selecting the Show Labels icon on thetoolbar

Figure 15.2 - Completed Geometry Model

6. Proceed with meshing the geometry model.

6a. First, discretize the surface into quad4 elements:

Surface List: Surface 1

Apply

◆ Finite Elements

Action: Create

Object: Mesh

Type: Surface

Global Edge Length: 10

Element Topology: Quad4

Show Labels

1

2 3

4

5

6

7

8

9

10

11

12

13

14

1 2 3 4 5 61

X

Y

Z


6b. To represent the stiffeners, generate bar elements along thelongitudinal edges of the surfaces. There is no need to specify a GlobalEdge Length since the mesher will utilize existing nodes generatedwhen you meshed the plate geometry with quad elements.

Note: The stiffener centroidal offsets are NOT taken into accountduring the discretization step. These offsets are specifiedwhen you define the Element Properties for the bar elements.

7. Equivalence the model to remove duplicate nodes at common sur-face edges.

Confirm deletion of 96 nodes in command line

Verify that there are no duplicate elements in the model.

Mesher: ◆ IsoMesh

Surface List:(select the entire model)

Surface 1:6

Apply

◆ Finite Elements

Action: Create

Object: Mesh

Type: Curve

Element Topology: Bar2

Curve List:(Select the entire model)

Apply

◆ Finite Elements

Action: Equivalence

Object: All

Method: Tolerance Cube

Apply

◆ Finite Elements



Confirm results of test in the command line.

Note: Confirming the test results in the command line is notnecessary. It is simply added to show you that MSC.Patranwill not create duplicate elements.

For clarity, hide the entity labels by selecting the Hide Labels icon onthe Top Menu Bar.

Figure 15.3 - The Completed Model with all Entity Labels Hidden

Action: Verify

Object: Element

Test: Duplicates

Apply

Hide Labels

X

Y

Z


8. Define a material using the specified modulus of elasticity, poissonratio and density.

In the Current Constitutive Models data box, you will see LinearElastic - [,,,,] - [Active] appear. Click on Cancel to close the form.

9. Reference the material you just defined when you specify elementproperties for your analysis model.

9a. First define properties for the quad4 elements which represent theplate.

◆ Materials

Action: Create

Object: Isotropic

Method: Manual Input

Material Name: alum

Input Properties ...

Constitutive Model: Linear Elastic

Elastic Modulus = 10E6

Poisson Ratio = 0.3

Density = 0.101

Apply

Cancel

◆ Properties

Action: Create

Dimension: 2D

Type: Shell

Property Set Name: plate


Material Name: m:alum

Thickness: 0.2



9b. Next, define properties for the bar2 elements which represent thestiffeners. For this model, in addition to bar orientation, area, areamoments of inertia, torsional constant and appropriate stress recoverycoefficients, we need to define offsets (See Hint on page 15-3).

Click on the Beam Library icon.

OK

Select Members:(Select the entire model)

Surface 1:6

Add

Apply

◆ Properties

Action: Create

Object: 1D

Method: Beam

Property Set Name: bar



(Use scroll bar on the right)

Bar Orientation: <0, 0, 1>

[Offset @ Node 1] <0, 0, -1.1>

[Offset @ Node 2] <0, 0, -1.1>


Confirm that the I-Beam cross-section is selected and then enter in thefollowing dimensions:

To change the view, click on the Iso 2 View button in the toolbar.

10. To view the three dimensional attributes of the stiffeners, proceed asfollows:

New Section Name: stiffener

H: 2.0

W1: 1.0

W2: 1.0

t: 0.1

t1: 0.15

t2: 0.15

OK

OK

Select Members:(Select the entire model)

Add

Apply

Display/Load/BC/Elem. Props...

Beam Display: 3D: Full-Span+Offsets

Apply

Cancel

I Section

Iso 2 View



Figure 15.4 - Viewport Display

Before defining loads & boundary conditions, modify your display asfollows:

11. Define displacement constraints and apply it to the geometry model.

Display/Load/BC/Elem. Props...

Beam Display: 1D: Line

Apply

Cancel

Display/Entity Color/Label/Render

Point: ■ Label

Apply

Cancel

X

Y

Z


11a. This boundary condition represents the simply supported corners ofthe stiffened plate structure.

◆ Loads/BCs

Action: Create

Object: Displacement

Method: Nodal

New Set Name: simply_support

Input Data...

Translation < T1 T2 T3 > < 0 0 0 >

OK

Select Application Region...

Geometry Filter: ◆ Geometry

Select Geometry Entities: Point 1 2 5 6 9 10 13 14

Add

OK

Apply



Figure 15.5 - Boundary Conditions

For clarity, hide the entity labels by selecting the Hide Labels icon onthe Top Menu Bar.

Reset the display by selecting the broom icon on the Top Menu Bar.

11b.Apply a uniform pressure load to the surface of the plate on which thestiffeners are mounted.

◆ Loads/BCs

Action: Create

Object: Pressure

123

123

123

123

123

123

123

123

X

Y

Z

Hide Labels

Reset Graphics


Note: Because the pressure loads are applied to the geometry modelinstead of the analysis model, it may appear as if the load wasnot applied correctly.

Figure 15.6 - Applied Pressure Loads

Method: Element Uniform

New Set Name: pressure

Target Element Type: 2D

Input Data...

Top Surf Pressure: 2.0

OK

Select Application Region...

Geometry Filter: ◆ Geometry

Select Surfaces or Edges: Surface 1:6

Add

OK

Apply

X

Y

Z 2.000

2.000

2.000

2.000

2.000

2.000

2.000

2.000

2.000

2.000

2.000

2.000

2.000

2.000

2.000

2.000

2.000

2.000

2.000

2.000

2.000

2.000

2.000

2.000

X

Y

Z




12. Now you are ready to generate an input file for analysis.

Click on the Analysis radio button on the Top Menu Bar and completethe entries as shown here.

An input file called lesson15_a.bdf will be generated. This processof translating your model into an input file is called the ForwardTranslation. The Forward Translation is complete when the Heartbeatturns green. MSC.Patran Users should proceed to Step 14.

◆ Analysis

Action: Analyze

Object: Entire Model

Method: Analysis Deck

Job Name: lesson15_a

Solution Type...

Solution Type: ◆ Linear Static

OK

Subcase Create...

Available Subcases:(highlight)

Default

Subcase Options: Output Requests

Select Result Type:(highlight)

Element Forces

OK

Apply

Cancel

Apply

Reset Graphics


Generating an input file for MSC.Nastran Users:MSC.Nastran users can generate an input file using the data fromTable 15.1. The result should be similar to the output below.

13. MSC.Nastran input file: lesson15_a.dat

SOL 101TIME 600CENDTITLE = lesson15_aECHO = NONEMAXLINES = 999999999SUBCASE 1 SUBTITLE=Default SPC = 2 LOAD = 2 DISPLACEMENT(SORT1,REAL)=ALL SPCFORCES(SORT1,REAL)=ALL STRESS(SORT1,REAL,VONMISES,BILIN)=ALL FORCE(SORT1,REAL,BILIN)=ALLBEGIN BULKPARAM POST -1PARAM PATVER 3.PARAM AUTOSPC YESPARAM INREL 0PARAM ALTRED NOPARAM COUPMASS -1PARAM K6ROT 0.PARAM WTMASS 1.PARAM,NOCOMPS,-1PARAM PRTMAXIM YES$ Elements and Element Properties for region : platePSHELL 1 1 .2 1 1CQUAD4 1 1 1 2 4 3CQUAD4 2 1 3 4 6 5CQUAD4 3 1 5 6 8 7CQUAD4 4 1 7 8 10 9CQUAD4 5 1 9 10 12 11CQUAD4 6 1 2 14 16 4CQUAD4 7 1 4 16 18 6CQUAD4 8 1 6 18 20 8CQUAD4 9 1 8 20 22 10CQUAD4 10 1 10 22 24 12CQUAD4 11 1 14 26 28 16CQUAD4 12 1 16 28 30 18CQUAD4 13 1 18 30 32 20CQUAD4 14 1 20 32 34 22CQUAD4 15 1 22 34 36 24CQUAD4 16 1 26 38 40 28CQUAD4 17 1 28 40 42 30CQUAD4 18 1 30 42 44 32CQUAD4 19 1 32 44 46 34CQUAD4 20 1 34 46 48 36CQUAD4 21 1 38 50 52 40CQUAD4 22 1 40 52 54 42CQUAD4 23 1 42 54 56 44CQUAD4 24 1 44 56 58 46



CQUAD4 25 1 46 58 60 48CQUAD4 26 1 50 62 64 52CQUAD4 27 1 52 64 66 54CQUAD4 28 1 54 66 68 56CQUAD4 29 1 56 68 70 58CQUAD4 30 1 58 70 72 60$ Elements and Element Properties for region : barPBARL 2 1 I + A+ A 2. 1. 1. .1 .15 .15CBAR 31 2 1 3 0. 0. 1. + B+ B 0. 0. -1.1 0. 0. -1.1CBAR 32 2 3 5 0. 0. 1. + C+ C 0. 0. -1.1 0. 0. -1.1CBAR 33 2 5 7 0. 0. 1. + D+ D 0. 0. -1.1 0. 0. -1.1CBAR 34 2 7 9 0. 0. 1. + E+ E 0. 0. -1.1 0. 0. -1.1CBAR 35 2 9 11 0. 0. 1. + F+ F 0. 0. -1.1 0. 0. -1.1CBAR 36 2 11 12 0. 0. 1. + G+ G 0. 0. -1.1 0. 0. -1.1CBAR 37 2 2 4 0. 0. 1. + H+ H 0. 0. -1.1 0. 0. -1.1CBAR 38 2 4 6 0. 0. 1. + I+ I 0. 0. -1.1 0. 0. -1.1CBAR 39 2 6 8 0. 0. 1. + J+ J 0. 0. -1.1 0. 0. -1.1CBAR 40 2 8 10 0. 0. 1. + K+ K 0. 0. -1.1 0. 0. -1.1CBAR 41 2 10 12 0. 0. 1. + L+ L 0. 0. -1.1 0. 0. -1.1CBAR 42 2 1 2 0. 0. 1. + M+ M 0. 0. -1.1 0. 0. -1.1CBAR 43 2 12 24 0. 0. 1. + N+ N 0. 0. -1.1 0. 0. -1.1CBAR 44 2 14 16 0. 0. 1. + O+ O 0. 0. -1.1 0. 0. -1.1CBAR 45 2 16 18 0. 0. 1. + P+ P 0. 0. -1.1 0. 0. -1.1CBAR 46 2 18 20 0. 0. 1. + Q+ Q 0. 0. -1.1 0. 0. -1.1CBAR 47 2 20 22 0. 0. 1. + R+ R 0. 0. -1.1 0. 0. -1.1CBAR 48 2 22 24 0. 0. 1. + S+ S 0. 0. -1.1 0. 0. -1.1CBAR 49 2 2 14 0. 0. 1. + T+ T 0. 0. -1.1 0. 0. -1.1CBAR 50 2 24 36 0. 0. 1. + U+ U 0. 0. -1.1 0. 0. -1.1CBAR 51 2 26 28 0. 0. 1. + V+ V 0. 0. -1.1 0. 0. -1.1CBAR 52 2 28 30 0. 0. 1. + W+ W 0. 0. -1.1 0. 0. -1.1CBAR 53 2 30 32 0. 0. 1. + X+ X 0. 0. -1.1 0. 0. -1.1CBAR 54 2 32 34 0. 0. 1. + Y


+ Y 0. 0. -1.1 0. 0. -1.1CBAR 55 2 34 36 0. 0. 1. + Z+ Z 0. 0. -1.1 0. 0. -1.1CBAR 56 2 14 26 0. 0. 1. + AA+ AA 0. 0. -1.1 0. 0. -1.1CBAR 57 2 36 48 0. 0. 1. + AB+ AB 0. 0. -1.1 0. 0. -1.1CBAR 58 2 38 40 0. 0. 1. + AC+ AC 0. 0. -1.1 0. 0. -1.1CBAR 59 2 40 42 0. 0. 1. + AD+ AD 0. 0. -1.1 0. 0. -1.1CBAR 60 2 42 44 0. 0. 1. + AE+ AE 0. 0. -1.1 0. 0. -1.1CBAR 61 2 44 46 0. 0. 1. + AF+ AF 0. 0. -1.1 0. 0. -1.1CBAR 62 2 46 48 0. 0. 1. + AG+ AG 0. 0. -1.1 0. 0. -1.1CBAR 63 2 26 38 0. 0. 1. + AH+ AH 0. 0. -1.1 0. 0. -1.1CBAR 64 2 48 60 0. 0. 1. + AI+ AI 0. 0. -1.1 0. 0. -1.1CBAR 65 2 50 52 0. 0. 1. + AJ+ AJ 0. 0. -1.1 0. 0. -1.1CBAR 66 2 52 54 0. 0. 1. + AK+ AK 0. 0. -1.1 0. 0. -1.1CBAR 67 2 54 56 0. 0. 1. + AL+ AL 0. 0. -1.1 0. 0. -1.1CBAR 68 2 56 58 0. 0. 1. + AM+ AM 0. 0. -1.1 0. 0. -1.1CBAR 69 2 58 60 0. 0. 1. + AN+ AN 0. 0. -1.1 0. 0. -1.1CBAR 70 2 38 50 0. 0. 1. + AO+ AO 0. 0. -1.1 0. 0. -1.1CBAR 71 2 60 72 0. 0. 1. + AP+ AP 0. 0. -1.1 0. 0. -1.1CBAR 72 2 62 64 0. 0. 1. + AQ+ AQ 0. 0. -1.1 0. 0. -1.1CBAR 73 2 64 66 0. 0. 1. + AR+ AR 0. 0. -1.1 0. 0. -1.1CBAR 74 2 66 68 0. 0. 1. + AS+ AS 0. 0. -1.1 0. 0. -1.1CBAR 75 2 68 70 0. 0. 1. + AT+ AT 0. 0. -1.1 0. 0. -1.1CBAR 76 2 70 72 0. 0. 1. + AU+ AU 0. 0. -1.1 0. 0. -1.1CBAR 77 2 50 62 0. 0. 1. + AV+ AV 0. 0. -1.1 0. 0. -1.1$ Material Record : alumMAT1 1 1.+7 .3 .101$ Nodes of the Entire ModelGRID 1 0. 0. 0.GRID 2 10. 0. 0.GRID 3 0. 10. 0.GRID 4 10. 10. 0.GRID 5 0. 20. 0.GRID 6 10. 20. 0.GRID 7 0. 30. 0.GRID 8 10. 30. 0.GRID 9 0. 39.9999 0.



GRID 10 10. 39.9999 0.GRID 11 0. 50. 0.GRID 12 10. 50. 0.GRID 14 20. 0. 0.GRID 16 20. 9.99999 0.GRID 18 20. 19.9999 0.GRID 20 20. 29.9999 0.GRID 22 20. 39.9999 0.GRID 24 20. 50. 0.GRID 26 30. 0. 0.GRID 28 30. 9.99999 0.GRID 30 30. 19.9999 0.GRID 32 30. 29.9999 0.GRID 34 30. 39.9999 0.GRID 36 30. 50. 0.GRID 38 40. 0. 0.GRID 40 40. 9.99999 0.GRID 42 40. 19.9999 0.GRID 44 40. 29.9999 0.GRID 46 40. 39.9999 0.GRID 48 40. 50. 0.GRID 50 50. 0. 0.GRID 52 50. 9.99999 0.GRID 54 50. 19.9999 0.GRID 56 50. 29.9999 0.GRID 58 50. 39.9999 0.GRID 60 50. 50. 0.GRID 62 60. 0. 0.GRID 64 60. 9.99999 0.GRID 66 60. 19.9999 0.GRID 68 60. 29.9999 0.GRID 70 60. 39.9999 0.GRID 72 60. 50. 0.$ Loads for Load Case : DefaultSPCADD 2 1LOAD 2 1. 1. 1$ Displacement Constraints of Load Set : simply_supportSPC1 1 123 1 11 14 24 38 48 + AW+ AW 62 72$ Pressure Loads of Load Set : pressurePLOAD4 1 1 -2. THRU 30ENDDATA


Submit the input file for analysis:

14. Submit the input file to MSC.Nastran for analysis.

14a. To submit the MSC.Patran .bdf file for analysis, find anavailable UNIX shell window. At the command promptenter: nastran lesson15_a.bdf scr=yes. Monitor the runusing the UNIX ps command.

14b. To submit the MSC.Nastran .dat file for analysis, find anavailable UNIX shell window. At the command promptenter: nastran lesson15_a.dat scr=yes. Monitor the runusing the UNIX ps command.

15. When the run is completed, edit the lesson15_a.f06 file and search for the word FATAL. If no matches exist, search for the word WARNING. Determine whether existing WARNING messages indicate modeling errors.



16. MSC.Nastran Users should proceed to Step 28. MSC.Patran Usersshould proceed to the next step.

17. Proceed with the Reverse Translation process, that is importing thelesson15_a.op2 results file into MSC.Patran. To do this, return to theAnalysis form and proceed as follows.

18. When the translation is complete bring up the Results form

Select Deformation to view physical changes of the model.

To select results, click on the Select Results icon.

Max Displacement = ____________________

◆ Analysis

Action: Read Output2

Object: Result Entities

Method: Translate

Select Results File...

Selected Results File: lesson15_a.op2

OK

Apply

◆ Results

Action: Create

Object: Deformation

Select Result Case(s): Default, Static Subcase

Select Deformation Result: Displacements, Translational

Apply

Select Result



To change the view, click on the Front View button in the toolbar.

19. Select Fringe to view the maximum bar forces.


To change the display attributes of the plot, click on the DisplayAttributes icon.

To display different options for the plot, click on the PlotOptions icon.

◆ Results

Action: Create

Object: Fringe


Select Fringe Result: Bar Forces, Translational

Style: Continuous

Style:

Width:

Domain: None

Apply

Reset Graphics

Front View

Select Result

Display Attributes

Plot Options



Max Bar Force = _______________

20. Now, determine the maximum shell force in the X-direction.


Max Shell Force, X-component = _______________

21. Now, determine the maximum shell force in the Y-direction.

Max Shell Force, Y-component = _______________

22. Now, determine the maximum bar stress.


◆ Results


Select Fringe Result: Shell Forces, Force Resultant

Quantity: X Component

Apply

◆ Results

Quantity: Y Component

Apply

◆ Results


Select Fringe Result: Bar Stress, Maximum Axial

Select Result

Select Result


Max Bar Stress = ____________________

23. Now, determine the maximum stress tensor in the X-direction.


Note: Selecting two positions by default will cause MSC.Patran to getonly the maximum value. There are choices for average/minimum, but we are searching for maximum.

Max Stress Tensor, X-component = ________________

24. Now, determine the maximum stress tensor in the Y-direction.

Max Stress Tensor, Y-component = _______________

Apply

◆ Results


Select Fringe Result: Stress Tensor

Position...(At Center)

Positions:(highlight both)

At Z1At Z2

Close


Apply

◆ Results


Apply

Select Result




Reset Graphics


25. Users who are not utilizing MSC.Patran for generating an input fileshould go to Step 28, otherwise, proceed to Step 26.

26. Now, let’s modify our 2D shell. In order to remove the bendingmaterial and corresponding forces, we need to simply make it aMembrane in MSC.Patran.


MSC.Patran will not modify the properties of the plate unless you firstverify that the properties are correct.

27. Click on the Analysis radio button on the Top Menu Bar and com-plete the entries as shown here.

◆ Properties

Select Property Set to Modify: plate

OK

Action: Modify

Dimension: 2D

Type: Membrane

Modify Properties ...


Thickness: 0.2

OK

Apply

◆ Analysis

Action: Analyze



Iso 2 View



An input file called lesson15_b.bdf will be generated. This processof translating your model into an input file is called the ForwardTranslation. The Forward Translation is complete when the Heartbeatturns green. MSC.Patran Users should proceed to Step 29.

Job Name: lesson15_b

Apply



28. MSC.Nastran input file: lesson15_b.dat

SOL 101TIME 600CENDTITLE = lesson15_bECHO = NONEMAXLINES = 999999999SUBCASE 1 SUBTITLE=Default SPC = 2 LOAD = 2 DISPLACEMENT(SORT1,REAL)=ALL SPCFORCES(SORT1,REAL)=ALL STRESS(SORT1,REAL,VONMISES,BILIN)=ALL FORCE(SORT1,REAL,BILIN)=ALLBEGIN BULKPARAM POST -1PARAM PATVER 3.PARAM AUTOSPC YESPARAM INREL 0PARAM ALTRED NOPARAM COUPMASS -1PARAM K6ROT 0.PARAM WTMASS 1.PARAM,NOCOMPS,-1PARAM PRTMAXIM YES$ Elements and Element Properties for region : platePSHELL 1 1 .2CQUAD4 1 1 1 2 4 3CQUAD4 2 1 3 4 6 5CQUAD4 3 1 5 6 8 7CQUAD4 4 1 7 8 10 9CQUAD4 5 1 9 10 12 11CQUAD4 6 1 2 14 16 4CQUAD4 7 1 4 16 18 6CQUAD4 8 1 6 18 20 8CQUAD4 9 1 8 20 22 10CQUAD4 10 1 10 22 24 12CQUAD4 11 1 14 26 28 16CQUAD4 12 1 16 28 30 18CQUAD4 13 1 18 30 32 20CQUAD4 14 1 20 32 34 22CQUAD4 15 1 22 34 36 24CQUAD4 16 1 26 38 40 28CQUAD4 17 1 28 40 42 30CQUAD4 18 1 30 42 44 32CQUAD4 19 1 32 44 46 34CQUAD4 20 1 34 46 48 36CQUAD4 21 1 38 50 52 40CQUAD4 22 1 40 52 54 42CQUAD4 23 1 42 54 56 44



CQUAD4 24 1 44 56 58 46CQUAD4 25 1 46 58 60 48CQUAD4 26 1 50 62 64 52CQUAD4 27 1 52 64 66 54CQUAD4 28 1 54 66 68 56CQUAD4 29 1 56 68 70 58CQUAD4 30 1 58 70 72 60$ Elements and Element Properties for region : barPBARL 2 1 I + A+ A 2. 1. 1. .1 .15 .15CBAR 31 2 1 3 0. 0. 1. + B+ B 0. 0. -1.1 0. 0. -1.1CBAR 32 2 3 5 0. 0. 1. + C+ C 0. 0. -1.1 0. 0. -1.1CBAR 33 2 5 7 0. 0. 1. + D+ D 0. 0. -1.1 0. 0. -1.1CBAR 34 2 7 9 0. 0. 1. + E+ E 0. 0. -1.1 0. 0. -1.1CBAR 35 2 9 11 0. 0. 1. + F+ F 0. 0. -1.1 0. 0. -1.1CBAR 36 2 11 12 0. 0. 1. + G+ G 0. 0. -1.1 0. 0. -1.1CBAR 37 2 2 4 0. 0. 1. + H+ H 0. 0. -1.1 0. 0. -1.1CBAR 38 2 4 6 0. 0. 1. + I+ I 0. 0. -1.1 0. 0. -1.1CBAR 39 2 6 8 0. 0. 1. + J+ J 0. 0. -1.1 0. 0. -1.1CBAR 40 2 8 10 0. 0. 1. + K+ K 0. 0. -1.1 0. 0. -1.1CBAR 41 2 10 12 0. 0. 1. + L+ L 0. 0. -1.1 0. 0. -1.1CBAR 42 2 1 2 0. 0. 1. + M+ M 0. 0. -1.1 0. 0. -1.1CBAR 43 2 12 24 0. 0. 1. + N+ N 0. 0. -1.1 0. 0. -1.1CBAR 44 2 14 16 0. 0. 1. + O+ O 0. 0. -1.1 0. 0. -1.1CBAR 45 2 16 18 0. 0. 1. + P+ P 0. 0. -1.1 0. 0. -1.1CBAR 46 2 18 20 0. 0. 1. + Q+ Q 0. 0. -1.1 0. 0. -1.1CBAR 47 2 20 22 0. 0. 1. + R+ R 0. 0. -1.1 0. 0. -1.1CBAR 48 2 22 24 0. 0. 1. + S+ S 0. 0. -1.1 0. 0. -1.1CBAR 49 2 2 14 0. 0. 1. + T+ T 0. 0. -1.1 0. 0. -1.1CBAR 50 2 24 36 0. 0. 1. + U+ U 0. 0. -1.1 0. 0. -1.1CBAR 51 2 26 28 0. 0. 1. + V+ V 0. 0. -1.1 0. 0. -1.1CBAR 52 2 28 30 0. 0. 1. + W+ W 0. 0. -1.1 0. 0. -1.1CBAR 53 2 30 32 0. 0. 1. + X+ X 0. 0. -1.1 0. 0. -1.1


CBAR 54 2 32 34 0. 0. 1. + Y+ Y 0. 0. -1.1 0. 0. -1.1CBAR 55 2 34 36 0. 0. 1. + Z+ Z 0. 0. -1.1 0. 0. -1.1CBAR 56 2 14 26 0. 0. 1. + AA+ AA 0. 0. -1.1 0. 0. -1.1CBAR 57 2 36 48 0. 0. 1. + AB+ AB 0. 0. -1.1 0. 0. -1.1CBAR 58 2 38 40 0. 0. 1. + AC+ AC 0. 0. -1.1 0. 0. -1.1CBAR 59 2 40 42 0. 0. 1. + AD+ AD 0. 0. -1.1 0. 0. -1.1CBAR 60 2 42 44 0. 0. 1. + AE+ AE 0. 0. -1.1 0. 0. -1.1CBAR 61 2 44 46 0. 0. 1. + AF+ AF 0. 0. -1.1 0. 0. -1.1CBAR 62 2 46 48 0. 0. 1. + AG+ AG 0. 0. -1.1 0. 0. -1.1CBAR 63 2 26 38 0. 0. 1. + AH+ AH 0. 0. -1.1 0. 0. -1.1CBAR 64 2 48 60 0. 0. 1. + AI+ AI 0. 0. -1.1 0. 0. -1.1CBAR 65 2 50 52 0. 0. 1. + AJ+ AJ 0. 0. -1.1 0. 0. -1.1CBAR 66 2 52 54 0. 0. 1. + AK+ AK 0. 0. -1.1 0. 0. -1.1CBAR 67 2 54 56 0. 0. 1. + AL+ AL 0. 0. -1.1 0. 0. -1.1CBAR 68 2 56 58 0. 0. 1. + AM+ AM 0. 0. -1.1 0. 0. -1.1CBAR 69 2 58 60 0. 0. 1. + AN+ AN 0. 0. -1.1 0. 0. -1.1CBAR 70 2 38 50 0. 0. 1. + AO+ AO 0. 0. -1.1 0. 0. -1.1CBAR 71 2 60 72 0. 0. 1. + AP+ AP 0. 0. -1.1 0. 0. -1.1CBAR 72 2 62 64 0. 0. 1. + AQ+ AQ 0. 0. -1.1 0. 0. -1.1CBAR 73 2 64 66 0. 0. 1. + AR+ AR 0. 0. -1.1 0. 0. -1.1CBAR 74 2 66 68 0. 0. 1. + AS+ AS 0. 0. -1.1 0. 0. -1.1CBAR 75 2 68 70 0. 0. 1. + AT+ AT 0. 0. -1.1 0. 0. -1.1CBAR 76 2 70 72 0. 0. 1. + AU+ AU 0. 0. -1.1 0. 0. -1.1CBAR 77 2 50 62 0. 0. 1. + AV+ AV 0. 0. -1.1 0. 0. -1.1$ Material Record : alumMAT1 1 1.+7 .3 .101$ Nodes of the Entire ModelGRID 1 0. 0. 0.GRID 2 10. 0. 0.GRID 3 0. 10. 0.GRID 4 10. 10. 0.GRID 5 0. 20. 0.GRID 6 10. 20. 0.GRID 7 0. 30. 0.GRID 8 10. 30. 0.



GRID 9 0. 39.9999 0.GRID 10 10. 39.9999 0.GRID 11 0. 50. 0.GRID 12 10. 50. 0.GRID 14 20. 0. 0.GRID 16 20. 9.99999 0.GRID 18 20. 19.9999 0.GRID 20 20. 29.9999 0.GRID 22 20. 39.9999 0.GRID 24 20. 50. 0.GRID 26 30. 0. 0.GRID 28 30. 9.99999 0.GRID 30 30. 19.9999 0.GRID 32 30. 29.9999 0.GRID 34 30. 39.9999 0.GRID 36 30. 50. 0.GRID 38 40. 0. 0.GRID 40 40. 9.99999 0.GRID 42 40. 19.9999 0.GRID 44 40. 29.9999 0.GRID 46 40. 39.9999 0.GRID 48 40. 50. 0.GRID 50 50. 0. 0.GRID 52 50. 9.99999 0.GRID 54 50. 19.9999 0.GRID 56 50. 29.9999 0.GRID 58 50. 39.9999 0.GRID 60 50. 50. 0.GRID 62 60. 0. 0.GRID 64 60. 9.99999 0.GRID 66 60. 19.9999 0.GRID 68 60. 29.9999 0.GRID 70 60. 39.9999 0.GRID 72 60. 50. 0.$ Loads for Load Case : DefaultSPCADD 2 1LOAD 2 1. 1. 1$ Displacement Constraints of Load Set : simply_supportSPC1 1 123 1 11 14 24 38 48 + AW+ AW 62 72$ Pressure Loads of Load Set : pressurePLOAD4 1 1 -2. THRU 30ENDDATA




29a. To submit the MSC.Patran .bdf file for analysis, find anavailable UNIX shell window. At the command promptenter: nastran lesson15_b.bdf scr=yes. Monitor the runusing the UNIX ps command.

29b. To submit the MSC.Nastran .dat file for analysis, find anavailable UNIX shell window. At the command promptenter: nastran lesson15_b.dat scr=yes. Monitor the runusing the UNIX ps command.

30. When the run is completed, edit the lesson15_b.f06 file and search for the word FATAL. If no matches exist, search for the word WARNING. Determine whether existing WARNING messages indicate modeling errors.



31. MSC.Nastran Users have finished this section. MSC.Patran Usersshould proceed to the next step.

32. Proceed with the Reverse Translation process, that is, importing thelesson15_b.op2 results file into MSC.Patran.

To do this, return to the Analysis form and proceed as follows:





◆ Analysis



Method: Translate


Selected Results File: lesson15_b.op2

OK

Apply

◆ Results

Action: Create

Object: Deformation

Select Result Case(s): Default, Static Subcase_2


Apply

Select Result






Note: The Domain under Plot Options does not need to be set toNone again because it was previously set in Step 12.

Max Bar Force = ____________________

35. Now, determine the maximum shell force in X-direction.


◆ Results

Action: Create

Object: Fringe



Apply

◆ Results


Select Fringe Result: Shell Forces, Force Resultant


Reset Graphics

Front View

Select Result

Select Result



Max Shell Force, X-component = ____________________

36. Now, determine the maximum shell force in Y-direction.

Max Shell Force, Y-component = ____________________



Max Bar Stress = _________________________

38. Now, determine the maximum stress tensor in the X-direction.


Apply

◆ Results


Apply

◆ Results



Apply

◆ Results


Select Result

Select Result


Note: Selecting two positions by default will cause MSC.Patran to getonly the maximum value. There are choices for average/minimum, but we are searching for maximum.

Max Stress Tensor, X-component = ____________________

39. Now, determine the maximum stress tensor in the Y-direction.

Max Stress Tensor, Y-component = ____________________

40. Now, determine the moment in each quad in the X-direction.

What value do you expect?


Select Fringe Result: Stress Tensor

Position...(At Center)

Positions:(highlight both)

At Z1At Z2

Close


Apply

◆ Results


Apply

◆ Results


Select Fringe Result: Shell Forces, Moment Resultant


Apply

Select Result



Moment in quad, X-component= ____________________

41. Now, determine the moment in each quad in the Y-direction.

Moment in quad, Y-component = ____________________

Note: Do the values for the moments in each quad make sense?



◆ Results


Apply

Reset Graphics

Iso 2 View


42. Users who are not utilizing MSC.Patran for generating an input fileshould go to Step 45, otherwise, proceed to Step 43.

43. Now, let’s modify our 2D membrane. In order to remove the mem-brane material and corresponding forces, we need to simply make ita Shear in MSC.Patran.

MSC.Patran will not modify the properties of the plate unless you firstverify that the properties are correct in the Modify Properties ... icon.

44. Click on the Analysis radio button on the Top Menu Bar and com-plete the entries as shown here.

◆ Properties

Select Property Set to Modify: plate

OK

Action: Modify

Dimension: 2D

Type: Shear Panel

Modify Properties ...


Thickness: 0.2

OK

Apply

◆ Analysis

Action: Analyze



Job Name: lesson15_c

Apply



An input file called lesson15_c.bdf will be generated. This process oftranslating your model into an input file is called the ForwardTranslation. The Forward Translation is complete when the Heartbeatturns green. MSC.Patran Users should proceed to Step 46.



45. MSC.Nastran input file: lesson15_c.dat

SOL 101TIME 600CENDTITLE = lesson15_cECHO = NONEMAXLINES = 999999999SUBCASE 1 SUBTITLE=Default SPC = 2 LOAD = 2 DISPLACEMENT(SORT1,REAL)=ALL SPCFORCES(SORT1,REAL)=ALL STRESS(SORT1,REAL,VONMISES,BILIN)=ALL FORCE(SORT1,REAL,BILIN)=ALLBEGIN BULKPARAM POST -1PARAM PATVER 3.PARAM AUTOSPC YESPARAM INREL 0PARAM ALTRED NOPARAM COUPMASS -1PARAM K6ROT 0.PARAM WTMASS 1.PARAM,NOCOMPS,-1PARAM PRTMAXIM YES$ Elements and Element Properties for region : platePSHEAR 1 1 .2CSHEAR 1 1 1 2 4 3CSHEAR 2 1 3 4 6 5CSHEAR 3 1 5 6 8 7CSHEAR 4 1 7 8 10 9CSHEAR 5 1 9 10 12 11CSHEAR 6 1 2 14 16 4CSHEAR 7 1 4 16 18 6CSHEAR 8 1 6 18 20 8CSHEAR 9 1 8 20 22 10CSHEAR 10 1 10 22 24 12CSHEAR 11 1 14 26 28 16CSHEAR 12 1 16 28 30 18CSHEAR 13 1 18 30 32 20CSHEAR 14 1 20 32 34 22CSHEAR 15 1 22 34 36 24CSHEAR 16 1 26 38 40 28CSHEAR 17 1 28 40 42 30CSHEAR 18 1 30 42 44 32CSHEAR 19 1 32 44 46 34CSHEAR 20 1 34 46 48 36CSHEAR 21 1 38 50 52 40CSHEAR 22 1 40 52 54 42CSHEAR 23 1 42 54 56 44



CSHEAR 24 1 44 56 58 46CSHEAR 25 1 46 58 60 48CSHEAR 26 1 50 62 64 52CSHEAR 27 1 52 64 66 54CSHEAR 28 1 54 66 68 56CSHEAR 29 1 56 68 70 58CSHEAR 30 1 58 70 72 60$ Elements and Element Properties for region : barPBARL 2 1 I + A+ A 2. 1. 1. .1 .15 .15CBAR 31 2 1 3 0. 0. 1. + B+ B 0. 0. -1.1 0. 0. -1.1CBAR 32 2 3 5 0. 0. 1. + C+ C 0. 0. -1.1 0. 0. -1.1CBAR 33 2 5 7 0. 0. 1. + D+ D 0. 0. -1.1 0. 0. -1.1CBAR 34 2 7 9 0. 0. 1. + E+ E 0. 0. -1.1 0. 0. -1.1CBAR 35 2 9 11 0. 0. 1. + F+ F 0. 0. -1.1 0. 0. -1.1CBAR 36 2 11 12 0. 0. 1. + G+ G 0. 0. -1.1 0. 0. -1.1CBAR 37 2 2 4 0. 0. 1. + H+ H 0. 0. -1.1 0. 0. -1.1CBAR 38 2 4 6 0. 0. 1. + I+ I 0. 0. -1.1 0. 0. -1.1CBAR 39 2 6 8 0. 0. 1. + J+ J 0. 0. -1.1 0. 0. -1.1CBAR 40 2 8 10 0. 0. 1. + K+ K 0. 0. -1.1 0. 0. -1.1CBAR 41 2 10 12 0. 0. 1. + L+ L 0. 0. -1.1 0. 0. -1.1CBAR 42 2 1 2 0. 0. 1. + M+ M 0. 0. -1.1 0. 0. -1.1CBAR 43 2 12 24 0. 0. 1. + N+ N 0. 0. -1.1 0. 0. -1.1CBAR 44 2 14 16 0. 0. 1. + O+ O 0. 0. -1.1 0. 0. -1.1CBAR 45 2 16 18 0. 0. 1. + P+ P 0. 0. -1.1 0. 0. -1.1CBAR 46 2 18 20 0. 0. 1. + Q+ Q 0. 0. -1.1 0. 0. -1.1CBAR 47 2 20 22 0. 0. 1. + R+ R 0. 0. -1.1 0. 0. -1.1CBAR 48 2 22 24 0. 0. 1. + S+ S 0. 0. -1.1 0. 0. -1.1CBAR 49 2 2 14 0. 0. 1. + T+ T 0. 0. -1.1 0. 0. -1.1CBAR 50 2 24 36 0. 0. 1. + U+ U 0. 0. -1.1 0. 0. -1.1CBAR 51 2 26 28 0. 0. 1. + V+ V 0. 0. -1.1 0. 0. -1.1CBAR 52 2 28 30 0. 0. 1. + W+ W 0. 0. -1.1 0. 0. -1.1CBAR 53 2 30 32 0. 0. 1. + X+ X 0. 0. -1.1 0. 0. -1.1


CBAR 54 2 32 34 0. 0. 1. + Y+ Y 0. 0. -1.1 0. 0. -1.1CBAR 55 2 34 36 0. 0. 1. + Z+ Z 0. 0. -1.1 0. 0. -1.1CBAR 56 2 14 26 0. 0. 1. + AA+ AA 0. 0. -1.1 0. 0. -1.1CBAR 57 2 36 48 0. 0. 1. + AB+ AB 0. 0. -1.1 0. 0. -1.1CBAR 58 2 38 40 0. 0. 1. + AC+ AC 0. 0. -1.1 0. 0. -1.1CBAR 59 2 40 42 0. 0. 1. + AD+ AD 0. 0. -1.1 0. 0. -1.1CBAR 60 2 42 44 0. 0. 1. + AE+ AE 0. 0. -1.1 0. 0. -1.1CBAR 61 2 44 46 0. 0. 1. + AF+ AF 0. 0. -1.1 0. 0. -1.1CBAR 62 2 46 48 0. 0. 1. + AG+ AG 0. 0. -1.1 0. 0. -1.1CBAR 63 2 26 38 0. 0. 1. + AH+ AH 0. 0. -1.1 0. 0. -1.1CBAR 64 2 48 60 0. 0. 1. + AI+ AI 0. 0. -1.1 0. 0. -1.1CBAR 65 2 50 52 0. 0. 1. + AJ+ AJ 0. 0. -1.1 0. 0. -1.1CBAR 66 2 52 54 0. 0. 1. + AK+ AK 0. 0. -1.1 0. 0. -1.1CBAR 67 2 54 56 0. 0. 1. + AL+ AL 0. 0. -1.1 0. 0. -1.1CBAR 68 2 56 58 0. 0. 1. + AM+ AM 0. 0. -1.1 0. 0. -1.1CBAR 69 2 58 60 0. 0. 1. + AN+ AN 0. 0. -1.1 0. 0. -1.1CBAR 70 2 38 50 0. 0. 1. + AO+ AO 0. 0. -1.1 0. 0. -1.1CBAR 71 2 60 72 0. 0. 1. + AP+ AP 0. 0. -1.1 0. 0. -1.1CBAR 72 2 62 64 0. 0. 1. + AQ+ AQ 0. 0. -1.1 0. 0. -1.1CBAR 73 2 64 66 0. 0. 1. + AR+ AR 0. 0. -1.1 0. 0. -1.1CBAR 74 2 66 68 0. 0. 1. + AS+ AS 0. 0. -1.1 0. 0. -1.1CBAR 75 2 68 70 0. 0. 1. + AT+ AT 0. 0. -1.1 0. 0. -1.1CBAR 76 2 70 72 0. 0. 1. + AU+ AU 0. 0. -1.1 0. 0. -1.1CBAR 77 2 50 62 0. 0. 1. + AV+ AV 0. 0. -1.1 0. 0. -1.1$ Material Record : alumMAT1 1 1.+7 .3 .101$ Nodes of the Entire ModelGRID 1 0. 0. 0.GRID 2 10. 0. 0.GRID 3 0. 10. 0.GRID 4 10. 10. 0.GRID 5 0. 20. 0.GRID 6 10. 20. 0.GRID 7 0. 30. 0.GRID 8 10. 30. 0.



GRID 9 0. 39.9999 0.GRID 10 10. 39.9999 0.GRID 11 0. 50. 0.GRID 12 10. 50. 0.GRID 14 20. 0. 0.GRID 16 20. 9.99999 0.GRID 18 20. 19.9999 0.GRID 20 20. 29.9999 0.GRID 22 20. 39.9999 0.GRID 24 20. 50. 0.GRID 26 30. 0. 0.GRID 28 30. 9.99999 0.GRID 30 30. 19.9999 0.GRID 32 30. 29.9999 0.GRID 34 30. 39.9999 0.GRID 36 30. 50. 0.GRID 38 40. 0. 0.GRID 40 40. 9.99999 0.GRID 42 40. 19.9999 0.GRID 44 40. 29.9999 0.GRID 46 40. 39.9999 0.GRID 48 40. 50. 0.GRID 50 50. 0. 0.GRID 52 50. 9.99999 0.GRID 54 50. 19.9999 0.GRID 56 50. 29.9999 0.GRID 58 50. 39.9999 0.GRID 60 50. 50. 0.GRID 62 60. 0. 0.GRID 64 60. 9.99999 0.GRID 66 60. 19.9999 0.GRID 68 60. 29.9999 0.GRID 70 60. 39.9999 0.GRID 72 60. 50. 0.$ Loads for Load Case : DefaultSPCADD 2 1LOAD 2 1. 1. 1$ Displacement Constraints of Load Set : simply_supportSPC1 1 123 1 11 14 24 38 48 + AW+ AW 62 72$ Pressure Loads of Load Set : pressurePLOAD2 1 -2. 1 THRU 7PLOAD2 1 -2. 8 THRU 14PLOAD2 1 -2. 15 THRU 21PLOAD2 1 -2. 22 THRU 28PLOAD2 1 -2. 29 30ENDDATA




46a. To submit the MSC.Patran .bdf file for analysis, find anavailable UNIX shell window. At the command promptenter: nastran lesson15_c.bdf scr=yes. Monitor the runusing the UNIX ps command.

46b. To submit the MSC.Nastran .dat file for analysis, find anavailable UNIX shell window. At the command promptenter: nastran lesson15_c.dat scr=yes. Monitor the runusing the UNIX ps command.

47. When the run is completed, edit the lesson15_c.f06 file and search for the word FATAL. If no matches exist, search for the word WARNING. Determine whether existing WARNING messages indicate modeling errors.



48. MSC.Nastran Users have finished this section. MSC.Patran Usersshould proceed to the next step.

49. Proceed with the Reverse Translation process, that is, importing thelesson15_c.op2 results file into MSC.Patran.

To do this, return to the Analysis form and proceed as follows:





◆ Analysis



Method: Translate


Selected Results File: lesson15_c.op2

OK

Apply

◆ Results

Action: Create

Object: Deformation



Apply

Select Result

15-48MSC.Nastran 105 Exercise Workbook





Note: The Domain under Plot Options does not need to be set toNone again because it was previously set in Step 12.

Max Bar Force = ____________________

52. Now, determine the maximum shell force.


◆ Results

Action: Create

Object: Fringe



Apply

◆ Results


Select Fringe Result: Shear Panel Stresses, Maximum Shear

Reset Graphics

Front View

Select Result

Select Result



Max Shear Panel Stress = ____________________



Max Bar Stress = _________________________

Quit MSC.Patran when you are finished with this exercise

Apply

◆ Results



Apply

Select Result


Lesson 15a

Lesson 15b

Lesson15c

Max Displacement: 2.11E-01

Max Bar Force: 3.56E+03

Max Shell Force, X-component: 1.40E+02

Max Shell Force, Y-component: 2.55E+02

Max Bar Stress: 1.61E+04

Max Stress Tensor, X-component: 1.21E+03

Max Stress Tensor, Y-component: 1.49E+03



Max Shell Force, X-component: 1.43E+02

Max Shell Force, Y-component: 2.58E+02

Max Bar Stress 1.56E+04

Max Stress Tensor, X-component: 7.15E+02

Max Stress Tensor, Y-component: 1.29E+03

Moment in quad, X-component: 0

Moment in quad, Y-component: 0



Max Shear Panel Stress: 1.01E+02

Max Bar Stress: 2.18E+04

linear static analysis of a simply-supported stiffened...

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