Hello,
Please clarify a straightforward way to extract axial force-moment data of shell elements. The project is a long descending tunnel with an oblique trend in plan view, so, the global and local coordinate systems are varying significantly along the tunnel axis.
Is there any FISH code available to use for this purpose?
Thank you.
Morteza
The best local coordinate system for a tunnel for plotting (e.g., force/moment) purpose is one of the local system axis is along the tunnel axial direction. For a tunnel with multiple parts with different axis, we would suggest plot part by part using the interactive range so that only one tunnel axes in the visualization.
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Thanks, @cheng!
If I may simplify your answer, are you suggesting setting different SurfX vectors corresponding to the variable tunnel part trends? That would be helpful if you could provide some examples.
Also, I assume there is no already-written FISH available to share with users for such common purposes.
Dear mrha,
The shell stress resultants are defined in terms of the surface coordinate system. For a complex tunnel, you need to establish this system separately for each tunnel segment (use the struct shell recover surface. . .command with the range logic to have it apply to a particular tunnel segment). After you do this, then you can obtain the resultants via FISH, and plot them. When you plot them you should check the USE-ENGINE box in the shell resultant plot item — this is explained in the attached snap.
For your case, you will probably need to use a FISH function to obtain the {axial force - moment) data from the stress resultants.
