Choose Layers > Loadings > Live (Reducible) Loading > All Loads Plan.
Double click the Area Load tool ().
In the Default Area Load Properties dialog box:
Change Fz to 40 psf and click OK.
This tool will now draw area loads of 40 psf.
Define an area load over the entire slab by clicking four corners of a quadrilateral and then typing "c". This shape need not match the slab’s exact dimensions, but should cover the slab.
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