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To model slabs with variable thickness and loading in SAFE/ETABS, it is best to create a base slab which spans the entire floor, then draw slabs of variable thickness over the base slab to adjust local geometry and loading. Contained-area slabs drawn over the base slab will take precedent. This applies to every area object except drop-panels. To apply variable loading, assign NONE properties to contained-area slabs (aka null areas), then select Assign > Load Data to specify load magnitude and direction. When assigning loads to null areas in both programs, loads will be added to the exiting existing base slab. See notes and table below for additional information:
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