I am facing a problem while designing a roof truss.
While designing the roof truss as a whole, the purlins are failing in output results on analysis
But passing when checked by selecting the beam individually.
Also when the purlin is designed individually alone with same properties and loads its getting passed. Kindly find the attachments for understanding the problem.
Regards,
Akshay Rana
whole roof truss.std purlin.std
Dear user,
Please notice the section you have used and the section it is showing in the screenshot. You have used ISMC 75 as shown below.
The design fails for ISMC75.
Now you have used "SELECT OPTIMIZED" command which has found the section which will be adequate to pass. That section is ISJC150.
You will find more details from the last steel design command in output.
Thanks for your answer Abhishek. But still one problem remains unsolved. The Purlin section ISMC 75 is failing in the Staad file "WHOLE ROOF TRUSS" whereas the same is passing in the other file named "PURLIN" for the same loading condition. It will be really helpful if you will give a review to these files and check the purlin design.
I tried to design member 44 with the commands CHECK CODE ALL and CHECK CODE MEMB 44 and the design results in both cases were the same - the member is failing with ration around 1.6. If you are not getting the same results, I would suggest you to upgrade to the latest STAAD.Pro version - 21.03.00.146.