I-Beam Analysis

Review stacking direction and element normals.

1. Open HyperWorks Desktop.
2. In the User Profiles dialog, set the profile to OptiStruct.
3. Open the model file, composite_beam.hm.
4. Open the composites panel by clicking 2D > composites > element normals.
5. Toggle from color display to vector display and click display. This will display the current element normals for displayed 2D elements.
   Note: For typical ply-based models with T junctions, cap element normals should point away from the web. Web element normals are arbitrary as long as the direction is consistent. Confirm that the element normals of the cap elements point away from the web and that web element normals point in the direction of global y.

   
   
   Figure 3.

Review the assigned material orientation.

1. Open the composites panel by clicking 2D > composites > material orientation.
2. Select the component on which material orientation will be reviewed by setting the middle top collector to comps and then selecting the ibeam component.
3. Click review to plot the current material orientation. The material orientation for this part has already been defined as the x direction of the local system with id = 1.

   
   
   Figure 4.

Create the plies that make up the composite laminate.

1. In the Model Browser, right-click in white space and select Create > Ply from the context menu.
2. Create the plies according to the table below. Notice that shapes are used in this laminate and are described in the image below of the I-beam cross section. Each shape should be the full lentgth of the beam.

   Ply Name	Ply ID	Material	Thickness	Orientation	Shape
   ply1	1	M40J	0.01	90	Top_cap
   ply2	2	M40J	0.01	0	Top_cap
   ply3	3	M40J	0.01	45	Left_web
   ply4	4	M40J	0.01	-45	Left_web
   ply5	5	M40J	0.01	90	Center_web
   ply6	6	M40J	0.01	45	Right_web
   ply7	7	M40J	0.01	-45	Right_web
   ply8	8	M40J	0.01	0	Bottom_cap
   ply9	9	M40J	0.01	90	Bottom_cap

   
   
   Figure 5.

Correct ply normals.

In models with T junctions that are modeled using a ply-based method, plies on each side of the web will have opposite stacking directions. On one side, the element stacking direction will be consistent with the cap, and on the other side it will not. See the image below.

Figure 6.

The discontinuity in stacking direction on the left side of the I-beam model will be corrected using ply normals. Ply normals manipulate the direction that an individual ply stacks.

Note: When ply normals are changed, a DRAPE table is created and assigned to the ply.

1. From the menu bar, click Tools > Orientation Review > Ply normals.
2. Toggle the Select ply arrows so that ply3 is active.
3. Click Apply to plot current ply normals. Note the discontinuity described above.
4. To correct ply normals, click the Pick elements > Elements collector twice to access the element selection panel.
5. Select only elements of the web and click proceed.
6. Click the Reverse radio button under Normals and then click Apply. This will plot corrected ply normals for ply3.
7. Reset the Display radio button under Normals to prevent any additional changes.
8. Confirm the web of ply3 has no discontinuity with the caps by repeating Step 2 and Step 3.
9. Repeat Step 3 through Step 8 for ply4.

Create the laminate. This stacks the previously created plies.

1. In the Model Browser, right-click in white space and select Create > Laminate from the context menu.
2. Under Type, select Sublaminate.
3. Under Name, type top.
4. Populate the ply table with ply1 and ply2.
5. Click Create.
6. Repeat Step 1 through Step 5 for the left, right, and bottom sublaminates according to the images below.

   
   
   Figure 7. Top

   Figure 8. Left

   
   
   

   
   
   Figure 9. Right

   
   
   Figure 10. Bottom

Create the interface laminate, which specifies how the sublaminates are joined.

The interface laminate contains a list of sublaminates. It also contains a list of interfaces that specify how sublaminates connect (interface) with each other. Each interface definition contains two inputs: interface ply1 and interface ply2. These are either the top most or bottom most ply of each sublaminate that interface. The order they are entered is the order the sublaminates are stacked, in the direction of the element normal. See the figure below for the correct interfaces for the I-beam.

Figure 11.

1. In the Model Browser, right-click in white space and select Create > Laminate from the context menu.
2. Under Type, select Interface Laminate.
3. Under Name, type interface.
4. In the sublaminate table, click in white space in the Sublaminate name column and select the top sublaminate from the list.
5. Add the left, right, and bottom sublaminates using the same method.
   Note: Five interfaces are required for the I-beam.
6. Right-click in white space and select Add Interface.
7. Create the 5 interfaces in the Interface definition table at the bottom of the dialog.
8. Define Interface ply1 and Interface ply2 for each interface using the values in the previous image.
9. Click Create to create the interface laminate.

   
   
   Figure 12.

Create two PCOMPP ply-based properties.

1. In the Model Browser, right-click on white space and select Create > Property from the context menu.
2. Set Card Image to PCOMPP.
3. Set Name to caps.
4. Set Z0 to 0.0. This defines the offset such that plies begin stacking from the location in space of the elements.
5. Assign the elements of the caps by right-clicking on the property in the Model Browser and selecting Assign from the context menu.

   
   
   Figure 13.

6. Repeat Step 1 through Step 3 for the web property. Leave Z0 as blank.
7. Assign the elements of the web by right-clicking on the property in the Model Browser and selecting Assign from the context menu.

   
   
   Figure 14.

   
   
   Figure 15.

Plot vectors that represent the ply1 and ply2 directions on each element.

1. From the menu bar, click Tools > Orientation Review.
2. Select the Ply directions tab.
3. Click Apply.
   This will plot the ply1 and ply2 directions for the current ply in the list.
4. To scroll through plies, click the << or >> icons under Select ply.
5. For ply3 and ply4, which have corrected ply normals, activate the Drape fiber orientation option.

   
   
   Figure 16.

Visualize the thickness and ply layers of the laminate.

1. Set Element Representation to 2D Detailed Element Representation. This will visualize the total thickness on each element.
2. Set the Composite Layers control to Composite Layers. This will display the individual layers within each element thickness.
3. Change the Element Color Mode to By Prop. This will color each layer by the color of the ply.
4. Recolor plies by shift selecting all plies in the ply folder, selecting one of the color icons, and clicking Auto color.
5. From the menu bar, select Preferences > Graphics and type 5 in the ply visualization thickness factor input. This will temporarily increase the displayed thickness of each ply layer for the purposes of visualization.
6. Confirm that all plies are in the expected order. If the interfaces were defined incorrectly, there will be discontinuities where portions of a ply jump to an unexpected location in the full stack.

   
   
   Figure 17.