ws4-1 workshop 4 stadium truss nas120, workshop 4, november 2003
Post on 18-Jan-2018
237 Views
Preview:
DESCRIPTION
TRANSCRIPT
WS4-1
WORKSHOP 4
Stadium Truss
NAS120, Workshop 4, November 2003
WS4-2NAS120, Workshop 4, November 2003
WS4-3NAS120, Workshop 4, November 2003
Problem Description Three truss designs are presented on the following pages. Select
one design and analyze it. The truss is made from steel with E = 30 x 106 psi and = 0.3. The cross-sectional area is A = 4.516 in2. The torsional constant is 37.398 in4. A 500-lb point load is applied at (60,168,0). The truss is bolted down at the Y=0 boundary. Model the truss with rod elements.
WS4-4NAS120, Workshop 4, November 2003
Workshop Objectives Build the truss model and analyze it. Determine the maximum
displacement and stresses. Is your design better than the arched-roof truss design presented in the Case Study?
Visualize the load path in the truss by plotting the rod element axial stresses. Follow the load from the load application point to the fixed base. Do the stresses make sense to you?
Become familiar with the .f06 file
WS4-5NAS120, Workshop 4, November 2003
Configuration #1
Problem Information
WS4-6NAS120, Workshop 4, November 2003
Configuration #2
WS4-7NAS120, Workshop 4, November 2003
Configuration #3
WS4-8NAS120, Workshop 4, November 2003
Suggested Exercise Steps1. Select a truss configuration to model2. Create a new database3. Create nodes and elements4. Create Material Properties 5. Create Physical Properties6. Apply Loads and Boundary Conditions7. Run the finite element analysis using MSC.Nastran8. Read the results into MSC.Patran9. Plot displacements and stresses10. Examine the .f06 file
WS4-9NAS120, Workshop 4, November 2003
Step 1. Choose a Truss Configuration
Configuration #1
WS4-10NAS120, Workshop 4, November 2003
Step 2. Create New Database
Create a new database called stadium_truss.db.
a. File / New.b. Enter stadium_truss as the
file name.c. Click OK.d. Choose Default Tolerance.e. Select MSC.Nastran as the
Analysis Code.f. Select Structural as the
Analysis Type.
g. Click OK.
a
d
e
f
gb c
WS4-11NAS120, Workshop 4, November 2003
Step 3. Create Nodes and Elements
Create the first node.a. Elements: Create / Node
/ Edit.b. Enter [420 0 0] for the
Node Location List.c. Click Apply.d. Click the Node size icon.
d d
a
b
c
WS4-12NAS120, Workshop 4, November 2003
Step 3. Create Nodes and Elements
Finish creating all 11 nodes.
WS4-13NAS120, Workshop 4, November 2003
Step 3. Create Nodes and Elements
Create an element between the first two nodes.
a. Elements: Create / Element / Edit.
b. Set the Shape to Bar, Topology to Bar 2, and Pattern to Standard.
c. Screen click on Node 1 and Node 2. An element is automatically created because Auto Execute is checked.
b
c
a
Node 1 Node 2
WS4-14NAS120, Workshop 4, November 2003
Finish creating all19 elements.
Step 3. Create Nodes and Elements
WS4-15NAS120, Workshop 4, November 2003
Step 4. Create Material Properties
Create an isotropic materiala. Materials: Create /
Isotropic / Manual Input.b. Under Material Name
input Steel.c. Click Input Properties,
then enter 30e6 for the elastic modulus and 0.3 for the Poisson Ratio.
d. Click OK.e. Click Apply.
a
e
b
d
c
d
WS4-16NAS120, Workshop 4, November 2003
Step 5. Create Physical Properties
Create physical properties for the rod elements
a. Properties: Create / 1 D / Rod.
b. Under Property Set Name input Circular_Rod.
c. Click Input Properties.d. Click on the Select Material
Icon e. Select steel for the material. f. Enter 4.516 for the Area.g. Enter 37.398 for the
Torsional Constant.h. Click OK.
a
b
c
df
e
g
h
WS4-17NAS120, Workshop 4, November 2003
Step 5. Create Physical Properties
Select application regiona. Click in the Select
Members Box.b. Select the Beam
element filter.c. Use the cursor to
drag across all elements
d. Click Add.e. Click Apply.
a
b
c
d
e
WS4-18NAS120, Workshop 4, November 2003
Step 6. Apply Loads and Boundary Conditions
Create the boundary conditiona. Loads/BCs: Create /
Displacement / Nodal.b. For the set name, input
Fixed.c. Click Input Data.d. Enter <0 0 0> for
Translations and <0 0 0> for Rotations.
e. Click OK.
a
b
c
d
e
WS4-19NAS120, Workshop 4, November 2003
Step 6. Apply Loads and Boundary Conditions
Apply the boundary conditiona. Click Select
Application Region.b. For the Geometry
Filter, select FEM.c. For the application
region, select the base of the truss.
d. Click Add.e. Click OK.
a
b
c
d
e
WS4-20NAS120, Workshop 4, November 2003
Finish creating the boundary condition
a. Click Apply.
Step 6. Apply Loads and Boundary Conditions
a
WS4-21NAS120, Workshop 4, November 2003
Step 6. Apply Loads and Boundary Conditions
Create another boundary condition to constrain DOFs not connected to any element
a. Loads/BCs: Create / Displacement / Nodal.
b. For the set name, input Unused_DOF.
c. Click Input Data.d. Enter < , ,0> for
Translations and < , ,0> for Rotations.
e. Click OK.
a
b
c
d
e
WS4-22NAS120, Workshop 4, November 2003
Step 6. Apply Loads and Boundary Conditions
Apply the displacementsa. Click Select
Application Region.b. For the Geometry
Filter, select FEM.c. For the application
region, select the rest of the truss.
d. Click Add.e. Click OK.f. Click Apply.
a
c
d
e
f
b
WS4-23NAS120, Workshop 4, November 2003
Create a load named forcea. Loads/BCs: Create / Force /
Nodal.b. For the New Set Name,
enter Force.c. Click Input Data.d. Enter a force of <0 –500 0>.e. Click OK.
Step 6. Apply Loads and Boundary Conditions
a
b
c
d
e
WS4-24NAS120, Workshop 4, November 2003
Step 6. Apply Loads and Boundary Conditions
Apply the load forcea. Click Select
Application Region.b. For the Geometry
Filter, select FEM.c. For the application
region, select the node at the tip of the truss as shown.
d. Click Add.e. Click OK.
a
b
c
d
e
WS4-25NAS120, Workshop 4, November 2003
Finish creating the loada. Click Apply.
Step 6. Apply Loads and Boundary Conditions
a
WS4-26NAS120, Workshop 4, November 2003
Step 7. Nastran Analysis
Analyze the modela. Analysis: Analyze / Entire
Model / Full Run.b. Click Solution Type c. Choose Linear Static.d. Click OK.e. Click Apply.
b
a
e
c
d
WS4-27NAS120, Workshop 4, November 2003
Step 8. Read Results File into Patran
Attach the results filea. Analysis: Access Results
/ Attach XDB / Result Entities.
b. Click Select Results File.
c. Choose the results file stadium_truss.xdb.
d. Click OK.e. Click Apply.
e
a
b
c
d
WS4-28NAS120, Workshop 4, November 2003
Step 9. Plot Displacements and Stresses
Create a quick plota. Results: Create / Quick
Plot.b. Select Stress Tensor
and X Component as the Fringe Result.
c. Select Displacements, Translational as the deformation result.
d. Click Apply. e. Record the maximum
displacement and maximum and minimum stress.
Max displacement = ______
Max X Stress = ______
Min X Stress = ______
a
b
c
d
WS4-29NAS120, Workshop 4, November 2003
Step 9. Plot Displacements and Stresses
a
b
d
e
f
Create a fringe plota. Results: Create / Fringe.b. Select Stress Tensor as
the Fringe Result.c. Select X Component as
the Fringe Result Quantity.
d. Click on the Plot Options Icon.
e. Set the Averaging Definition Domain to None.
f. Click Apply.
c
WS4-30NAS120, Workshop 4, November 2003
Step 9. Plot Displacements and Stresses
View the un-averaged resultsa. Note the change in
maximum stress.
Un-averaged Max Stress =
____________________
Un-averaged Min Stress =
____________________
WS4-31NAS120, Workshop 4, November 2003
Step 10. Examine the .f06 File
Examine the .f06 filea. Open the directory in
which your database is saved.
b. Find the file titled stadium_truss.f06 .
c. Open this file with any text editor.
d. Verify that the displacement and stress results agree with the graphical results shown in Patran.
WS4-32NAS120, Workshop 4, November 2003
Step 1. Choose a Truss Configuration
Configuration #2
WS4-33NAS120, Workshop 4, November 2003
Step 2. Create New Database
Create a new database called stadium_truss.db.
a. File / New.b. Enter stadium_truss as the
file name.c. Click OK.d. Choose Default Tolerance.e. Select MSC.Nastran as the
Analysis Code.f. Select Structural as the
Analysis Type.
g. Click OK.
a
d
e
f
gb c
WS4-34NAS120, Workshop 4, November 2003
Step 3. Create Nodes and Elements
Create the first node.a. Elements: Create / Node
/ Edit.b. Enter [420 0 0] for the
Node Location List.c. Click Apply.d. Click the Node Size icon.
d d
a
b
c
WS4-35NAS120, Workshop 4, November 2003
Step 3. Create Nodes and Elements
Finish creating all 9 nodes.
WS4-36NAS120, Workshop 4, November 2003
Step 3. Create Nodes and Elements
Create an element between the first two nodes.
a. Elements: Create / Element / Edit.
b. Set the Shape to Bar, Topology to Bar 2, and Pattern to Standard.
c. Screen click on Node 1 and Node 2. An element is automatically created because Auto Execute is checked.
b
c
a
Node 1 Node 2
WS4-37NAS120, Workshop 4, November 2003
Finish creating all15 elements.
Step 3. Create Nodes and Elements
WS4-38NAS120, Workshop 4, November 2003
Step 4. Create Material Properties
Create an isotropic materiala. Materials: Create /
Isotropic / Manual Input.b. Under Material Name
input Steel.c. Click Input Properties,
then enter 30e6 for the elastic modulus and 0.3 for the Poisson Ratio.
d. Click OK.e. Click Apply.
a
e
b
d
c
d
WS4-39NAS120, Workshop 4, November 2003
Step 5. Create Physical Properties
Create physical properties for the rod elements
a. Properties: Create / 1 D / Rod.
b. Under Property Set Name input Circular_Rod.
c. Click Input Properties. d. Click on the Select
Material icon. e. Select steel for the
material. f. Enter 4.516 for the
Area.g. Enter 37.398 for the
Torsional Constant.h. Click OK.
a
b
df
e
g
c
h
WS4-40NAS120, Workshop 4, November 2003
Step 5. Create Physical Properties
Select application regiona. Click in the Select
Members Box.b. Select the Beam
element filter.c. Use the cursor to
drag across all elements
d. Click Add.e. Click Apply.
a
b
c
d
e
WS4-41NAS120, Workshop 4, November 2003
Step 6. Apply Loads and Boundary Conditions
Create the boundary conditiona. Loads/BCs: Create /
Displacement / Nodal.b. For the set name, input
Fixed.c. Click Input Data.d. Enter <0 0 0> for
Translations and <0 0 0> for Rotations.
e. Click OK.
a
b
c
d
e
WS4-42NAS120, Workshop 4, November 2003
Step 6. Apply Loads and Boundary Conditions
Apply the boundary conditiona. Click Select
Application Region.b. For the Geometry
Filter, select FEM.c. For the application
region, select the base of the truss.
d. Click Add.e. Click OK.
a
b
c
d
e
WS4-43NAS120, Workshop 4, November 2003
Finish creating the boundary condition
a. Click Apply.
Step 6. Apply Loads and Boundary Conditions
a
WS4-44NAS120, Workshop 4, November 2003
Step 6. Apply Loads and Boundary Conditions
Create another boundary condition to constrain DOFs not connected to any element
a. Loads/BCs: Create / Displacement / Nodal.
b. For the set name, input Unused_DOF.
c. Click Input Data.d. Enter < , ,0> for
Translations and < , ,0> for Rotations.
e. Click OK.
a
b
c
d
e
WS4-45NAS120, Workshop 4, November 2003
Step 6. Apply Loads and Boundary Conditions
Apply the displacementsa. Click Select
Application Region.b. For the Geometry
Filter, select FEM.c. For the application
region, select the rest of the truss.
d. Click Add.e. Click OK.f. Click Apply.
a
c
d
ef
b
WS4-46NAS120, Workshop 4, November 2003
Create a load named forcea. Loads/BCs: Create / Force /
Nodal.b. For the New Set Name,
enter Force.c. Click Input Data.d. Enter a force of <0 –500 0>.e. Click OK.
Step 6. Apply Loads and Boundary Conditions
a
b
c
d
e
WS4-47NAS120, Workshop 4, November 2003
Step 6. Apply Loads and Boundary Conditions
Apply the load forcea. Click Select
Application Region.b. For the Geometry
Filter, select FEM.c. For the application
region, select the node below the tip of the truss as shown.
d. Click Add.e. Click OK.
a
b
c
d
e
WS4-48NAS120, Workshop 4, November 2003
Finish creating the loada. Click Apply.
Step 6. Apply Loads and Boundary Conditions
a
WS4-49NAS120, Workshop 4, November 2003
Step 7. Nastran Analysis
Analyze the modela. Analysis: Analyze / Entire
Model / Full Run.b. Click Solution Type c. Choose Linear Static.d. Click OK.e. Click Apply.
b
a
e
c
d
WS4-50NAS120, Workshop 4, November 2003
Step 8. Read Results File into Patran
Attach the results filea. Analysis: Access Results
/ Attach XDB / Result Entities.
b. Click Select Results File.
c. Choose the results file stadium_truss.xdb.
d. Click OK.e. Click Apply.
e
a
b
c
d
WS4-51NAS120, Workshop 4, November 2003
Step 9. Plot Displacements and Stresses
Create a quick plota. Results: Create / Quick
Plot.b. Select Stress Tensor
and X Component as the Fringe Result.
c. Select Displacements, Translational as the deformation result.
d. Click Apply. e. Record the maximum
displacement and maximum and minimum stress.
Max displacement = ______
Max X Stress = ______
Min X Stress = ______
a
b
c
d
WS4-52NAS120, Workshop 4, November 2003
Step 9. Plot Displacements and Stresses
a
b
d
e
f
Create a fringe plota. Results: Create / Fringe.b. Select Stress Tensor as
the Fringe Result.c. Select X Component as
the Fringe Result Quantity.
d. Click on the Plot Options Icon.
e. Set the Averaging Definition Domain to None.
f. Click Apply.
c
WS4-53NAS120, Workshop 4, November 2003
Step 9. Plot Displacements and Stresses
View the un-averaged resultsa. Note the change in
maximum stress.
Un-averaged Max Stress =
____________________
Un-averaged Min Stress =
____________________
WS4-54NAS120, Workshop 4, November 2003
Step 10. Examine the .f06 File
Examine the .f06 filea. Open the directory in
which your database is saved.
b. Find the file titled stadium_truss.f06 .
c. Open this file with any text editor.
d. Verify that the displacement and stress results agree with the graphical results shown in Patran.
WS4-55NAS120, Workshop 4, November 2003
Step 1. Choose a Truss Configuration
Configuration #3
WS4-56NAS120, Workshop 4, November 2003
Step 2. Create New Database
Create a new database called stadium_truss.db.
a. File / New.b. Enter stadium_truss as the
file name.c. Click OK.d. Choose Default Tolerance.e. Select MSC.Nastran as the
Analysis Code.f. Select Structural as the
Analysis Type.
g. Click OK.
a
d
e
f
gb c
WS4-57NAS120, Workshop 4, November 2003
Step 3. Create Nodes and Elements
Create the first node.a. Elements: Create / Node
/ Edit.b. Enter [420 0 0] for the
Node Location List.c. Click Apply.d. Click the Node Size icon.
d d
a
b
c
WS4-58NAS120, Workshop 4, November 2003
Step 3. Create Nodes and Elements
Finish creating all 18 nodes.
WS4-59NAS120, Workshop 4, November 2003
Step 3. Create Nodes and Elements
Create an element between the first two nodes.
a. Elements: Create / Element / Edit.
b. Set the Shape to Bar, Topology to Bar 2, and Pattern to Standard.
c. Screen click on Node 1 and Node 2. An element is automatically created because Auto Execute is checked.
b
c
a
Node 1 Node 2
WS4-60NAS120, Workshop 4, November 2003
Finish creating all 34 elements.
Step 3. Create Nodes and Elements
WS4-61NAS120, Workshop 4, November 2003
Step 4. Create Material Properties
Create an isotropic materiala. Materials: Create /
Isotropic / Manual Input.b. Under Material Name
input Steel.c. Click Input Properties,
then enter 30e6 for the Elastic Modulus and 0.3 for the Poisson Ratio.
d. Click OK.e. Click Apply.
a
e
b
d
c
d
WS4-62NAS120, Workshop 4, November 2003
df
e
g
Step 5. Create Physical Properties
Create physical properties for the rod elements
a. Properties: Create / 1 D / Rod.
b. Under Property Set Name input Circular_Rod.
c. Click Input Properties.d. Click on the Select Material
Icon. e. Select steel for the material. f. Enter 4.516 for the Area.g. Enter 37.398 for the
Torsional Constant.h. Click OK.
a
b
c
h
WS4-63NAS120, Workshop 4, November 2003
Step 5. Create Physical Properties
Select application regiona. Click in the Select
Members Box.b. Select the Beam
element filter.c. Use the cursor to
drag across all elements
d. Click Add.e. Click Apply.
a
b
c
d
e
WS4-64NAS120, Workshop 4, November 2003
Step 6. Apply Loads and Boundary Conditions
Create the boundary conditiona. Loads/BCs: Create /
Displacement / Nodal.b. For the set name, input
Fixed.c. Click Input Data.d. Enter <0 0 0> for
Translations and <0 0 0> for Rotations.
e. Click OK.
a
b
c
d
e
WS4-65NAS120, Workshop 4, November 2003
Step 6. Apply Loads and Boundary Conditions
Apply the boundary conditiona. Click Select
Application Region.b. For the Geometry
Filter, select FEM.c. For the application
region, select the base of the truss.
d. Click Add.e. Click OK.
a
b
c
d
e
WS4-66NAS120, Workshop 4, November 2003
Finish creating the boundary condition
a. Click Apply.
Step 6. Apply Loads and Boundary Conditions
a
WS4-67NAS120, Workshop 4, November 2003
Step 6. Apply Loads and Boundary Conditions
Create another boundary condition to constrain DOFs not connected to any element
a. Loads/BCs: Create / Displacement / Nodal.
b. For the set name, input Unused_DOF.
c. Click Input Data.d. Enter < , ,0> for
Translations and < , ,0> for Rotations.
e. Click OK.
a
b
c
d
e
WS4-68NAS120, Workshop 4, November 2003
Step 6. Apply Loads and Boundary Conditions
Apply the displacementsa. Click Select
Application Region.b. For the Geometry
Filter, select FEM.c. For the application
region, select the rest of the truss.
d. Click Add.e. Click OK.f. Click Apply.
a
c
d
e
f
b
WS4-69NAS120, Workshop 4, November 2003
Create a load named forcea. Loads/BCs: Create / Force /
Nodal.b. For the New Set Name,
enter Force.c. Click Input Data.d. Enter a force of <0 –500 0>.e. Click OK.
Step 6. Apply Loads and Boundary Conditions
a
b
c
d
e
WS4-70NAS120, Workshop 4, November 2003
Step 6. Apply Loads and Boundary Conditions
Apply the load forcea. Click Select
Application Region.b. For the Geometry
Filter, select FEM.c. For the application
region, select the node at the tip of the truss as shown.
d. Click Add.e. Click OK.
a
b
c
d
e
WS4-71NAS120, Workshop 4, November 2003
Finish creating the loada. Click Apply.
Step 6. Apply Loads and Boundary Conditions
a
WS4-72NAS120, Workshop 4, November 2003
Step 7. Nastran Analysis
Analyze the modela. Analysis: Analyze / Entire
Model / Full Run.b. Click Solution Type c. Choose Linear Static.d. Click OK.e. Click Apply.
b
a
e
c
d
WS4-73NAS120, Workshop 4, November 2003
Step 8. Read Results File into Patran
Attach the results filea. Analysis: Access Results
/ Attach XDB / Result Entities.
b. Click Select Results File.
c. Choose the results file stadium_truss.xdb.
d. Click OK.e. Click Apply.
e
a
b
c
d
WS4-74NAS120, Workshop 4, November 2003
Step 9. Plot Displacements and Stresses
Create a quick plota. Results: Create / Quick
Plot.b. Select Stress Tensor
and X Component as the Fringe Result.
c. Select Displacements, Translational as the deformation result.
d. Click Apply. e. Record the maximum
displacement and maximum and minimum stress.
Max displacement = ______
Max X Stress = ______
Min X Stress = ______
a
b
c
d
WS4-75NAS120, Workshop 4, November 2003
Step 9. Plot Displacements and Stresses
Create a fringe plota. Results: Create / Fringe.b. Select Stress Tensor as
the Fringe Result.c. Select X Component as
the Fringe Result Quantity.
d. Click on the Plot Options Icon.
e. Set the Averaging Definition Domain to None.
f. Click Apply.
a
b
d
e
f
c
WS4-76NAS120, Workshop 4, November 2003
Step 9. Plot Displacements and Stresses
View the un-averaged resultsa. Note the change in
maximum stress.
Un-averaged Max Stress =
____________________
Un-averaged Min Stress =
____________________
WS4-77NAS120, Workshop 4, November 2003
Step 10. Examine the .f06 File
Examine the .f06 filea. Open the directory in
which your database is saved.
b. Find the file titled stadium_truss.f06 .
c. Open this file with any text editor.
d. Verify that the displacement and stress results agree with the graphical results shown in Patran.
WS4-78NAS120, Workshop 4, November 2003
top related