Thank you very much for you reply.
I have followed your instruction above. But I could not force staad to use my custom-defined sections. Can you please have a brief look at the commands below and tell me what was not correct (this is just a test problem, the force and sections were selected...
I am just a beginner in staad pro.
After applying a moving load on a beam, I want to find exact the position on that beam which has maximum bending moment Mz caused by that moving load. (If I go to post-analysis, the beam is divided into 12 sections and I can only find position of max bending...