How do you use load envelopes and load lists in STAAD to compare different load cases?

2 How to create load cases and combinations in STAAD?

To create load cases and combinations in STAAD, you need to use the LOAD and LOAD COMBINATION commands in the input file or use the graphical user interface (GUI). For instance, to create a dead load case and a live load case, you can use the commands, ‘LOAD 1 DEAD LOAD’ followed by ‘SELFWEIGHT Y -1’, and ‘MEMBER LOAD 1 TO 10 UNI Y -10’. Similarly, for a live load case, you can use ‘LOAD 2 LIVE LOAD’ followed by ‘MEMBER LOAD 1 TO 10 UNI Y -15’. To create a load combination of 1.2D + 1.6L, you can use the command, ‘LOAD COMBINATION 3 1.2 1 + 1.6 2’. Alternatively, you can also use the GUI to create load cases and combinations by clicking on the Load tab and selecting the appropriate options.

3 How to use load envelopes in STAAD?

Load envelopes are graphical representations of the maximum and minimum values of a certain parameter (such as bending moment, shear force, deflection, etc.) for all the load cases or combinations. They are useful for finding the critical sections of the structure and for designing the members accordingly. To use load envelopes in STAAD, you need to use the ENVELOPE command in the input file, or use the GUI to select the load cases or combinations that you want to include in the envelope. For example, to create an envelope of bending moment for load cases 1 and 2, you can use the following command:

ENVELOPE 1 2

You can also use the GUI to create load envelopes by clicking on the Post-Processing tab and selecting the Envelope option.

4 How to use load lists in STAAD?

Load lists are tables that show the values of a certain parameter (such as bending moment, shear force, deflection, etc.) for each load case or combination at a specified location or member. They are useful for comparing the effects of different load cases or combinations on the structure and for checking the design criteria. To use load lists in STAAD, you need to use the PRINT command in the input file, or use the GUI to select the load cases or combinations and the parameter that you want to display. For example, to create a load list of bending moment for load combination 3 at member 5, you can use the following command:

PRINT MEMBER FORCES

LOAD LIST 3

MEMBER LIST 5

You can also use the GUI to create load lists by clicking on the Post-Processing tab and selecting the Member Query option.

5 How to compare load cases and combinations in STAAD?

To compare load cases and combinations in STAAD, you can use both load envelopes and load lists, depending on your purpose and preference. Load envelopes can help you visualize the maximum and minimum values of a parameter for all the load cases or combinations, and identify the critical sections of the structure. Load lists can help you compare the values of a parameter for each load case or combination at a specific location or member, and check the design criteria. You can also use the Report option in the GUI to generate a comprehensive report of the analysis and design results for all the load cases and combinations.