Hi, in response to your query I will upload the foundation file as well as the staad pro file, so you could have a better understanding of the situation. I actually wish to design a mat footing for a 2-storey building but when I tried to design it using staad foundation I had punching shear failure in the area where there were no column, and the areas with columns actually passed. Therefore I ran another model without any columns just to test the punching shear and all the points were failing no matter the thickness of the slab. Both files have been added within the following compressed folder.
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