The Design Punching Shear command calculates an applied load on the slab, accounting for the difference in column/wall axial load and bending. In addition, the command checks the slab shear stresses, accounting for the reinforcement present (background and column/general patches).
Provided that you are using the Eurocode or ACI head code, you can also design the punching reinforcement as an orthogonal or circular arrangement of stud rails at the following locations:
In flat slabs:
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Concrete columns supporting a flat slab without drops
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Concrete columns supported by a flat slab
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Concrete columns through a flat slab without drops
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Point loads at either face of a flat slab
Column head drops and the presence of openings within a certain distance of the punching shear boundary are taken into account in the punching shear calculations.
Where punching checks are closely spaced and the perimeters overlap the checks are beyond scope.
Note: -
Since the checks are dependent on using the correct levels of slab reinforcement (typically provided by patch reinforcement), do not check punching before designing the patches.
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View punching checks applied to walls with caution. Their applicability to long walls is particularly questionable, as the check does not consider the potential for stress concentrations at the ends of the wall.