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Reentrant corner irregularity is defined to exist where dimensions of projections in both plan projections of the structure beyond a reentrant corner are greater than 15% of the plan dimension of the structure in the given direction.
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of the two perpendicular directions in plan exceed the total plan dimensions of that story of the building in the respective directions by more than 15%
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In buildings with reentrant corner type irregularities, story slabs is modelled with two-dimensional plate (membrane) or shell finite elements to show that they are able to safely transfer earthquake forces between vertical bearing system elements in their own planes.
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