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Hint As with the Displacement results, you can use the [Pg Up] and [Pg Dn] keys (or the toolbar equivalents) to scroll through the different load combinations. Use of the

interactive review options can often be a more efficient way of reviewing output results as compared to searching for data in batch reports.

10. Press the Cancel button to terminate the Forces and Moments review.

11. Select File > Save.

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Having already reviewed stresses, deflections, and loads, we will now iterate through a design change. AutoPIPE facilitates this process by helping you to quickly re-run an analysis to determine whether a design change produced the desired effect.

1. Pick point A01 N.

2. Select Insert/Support.

3. Select Guide from the Support type field.

4. Press OK to accept the defaults and close the dialog. The Guide is placed in the model as shown in the following figure.

DESIGN CHANGE

5. Select View > Solid Model View to display a 3D representation of the model.

6. After adding the new component, you have to re-run the static analysis; otherwise, the results (based on the addition of the guide support) will not reflect the properties of the design change. Select the Static Analysis button on the toolbar.

Hint As mentioned previously, the Static Analysis toolbar button runs a static analysis using the last set of options defined in the dialog. Use the toolbar button when re-running an analysis. Use the menu command to define new analysis criteria.

7. Select Result > Code Stresses to check the piping code stress results.

8. Press OK to accept the defaults and review the stress ratios. A color-coded stress plot of the model is displayed. Note that the red areas help you to quickly determine where the system is still overstressed.

A guide is placed at bend near point A01 N.

DESIGN CHANGE

9. Press Cancel to exit interactive stress review.

10. The Guide support did not solve the stress problem. "Undo" the design change by selecting Edit > Undo. The Guide is removed from the model.

11. You will now try another design change in which we add length to the first elbow in order to add flexibility. Pick point A01 to make it active.

12. Select Modify > Bend, or double-click on point A01.

The red areas in the display help to quickly locate areas of high stress.

DESIGN CHANGE

16. Let's see if the new design change helps to alleviate the points of high stress in the system.

Press the Static Analysis toolbar button to re-analyze the system.

17. Select Result > Code Stresses.

18. The stress plot of the system is shown below. Move the information dialog to the right and review the new results. Note that the model no longer exceeds code stress allowables. The maximum stress ratio is now 0.92 {0.93} at A01 N+ (inside the bend) and thus there are no longer any red areas in the model.

The length of this run was extended.

DESIGN CHANGE

CHAPTER REVIEW

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Assigning Loads: There are different methods for assigning loads depending on whether the load is being assigned to a point or to an entire system. For example, in this chapter you learned how to assign a Concentrated Force to a specific point in the model using the Loads/Concentrated Force command. A thermal load was also applied to an anchor point by inputting the load value inside the Anchor dialog. An earthquake load was assigned to the entire system by selecting Loads/Static Earthquake. From the dialog, you may define the number of earthquake load cases and input values as multiples of gravity.

Performing a Static Analysis: The Static Analysis command analyzes the effects of different loads on your system. A dialog is presented in which you may select which loads to include in the analysis. Obviously, loads must be defined in the model before they can be analyzed. To include a non-linear analysis, ensure that the Gaps/Friction/Soil option has been enabled in the Static Load Cases dialog. To re-run a static analysis with the previous set of load options, use the Static Analysis toolbar button. To run an analysis with new options, use the Analyze/Static menu command.

Graphical Review of Code Stresses: After loads have been assigned and a static analysis performed, you can review the results of code stresses. Many of these commands are available in the Result menu. For example, select Result/Code Stresses to produce a color-coded plot of stresses in the model. A legend will appear to the left of the modeling area to help you to quickly identify areas of concern in the system.

Displaying Load Combinations: The Tools/Display Combinations command helps you to identify the loads that have been defined in the system. Of particular note in this dialog is the “Non-Code Comb.” column, which lists user-defined non-code combinations. By default, AutoPIPE will assume that you want to define these combination sets manually, as different users and systems have different requirements.

User Defined Load Combinations: Use the Tools/User-Defined Combinations/Non-Code command to input “Non-Code Comb.” combination sets. A dialog allows you to name the code for identification in reports, and to assign multiple Case/Combinations and associated Factors.

Interactive Review: A variety of graphical and point information is available for reviewing code results. A deflected shape plot of the model can be produced with the Result/Displacement command. The Result/Force & Moment command helps to review the Forces and Moments loads associated with a selected point.

Design Changes: Use the Result/Code Stresses command to check the piping code stress results.

AutoPIPE will highlight high stress areas in red that may be out of range. You can then make a design change, re-run the Static Analysis command, and confirm the results using the Result/Code Stresses command again. This technique allows you to quickly confirm the success/failure of a design change implemented to satisfy code compliance requirements.