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D9.A.4.2 Design for Shear

The Design Shear value, QD, is evaluated for the beam. The update effective depth is used to then calculate the allowable shear stress. The allowable shear stress of concrete, fs, is automatically calculated from design load type (permanent or temporary) and given density of concrete. The program then calculates the required bar size, aw, and spacing of stirrups. The reinforcement ratio for the stirrup, pw, is calculated for design Bar size and stirrup pitch and all the necessary checking is done.

For seismic loading it is needed to increase shear force ≥ 1.5 times the actual value and this can be done utilizing the Design Shear Modification factor, k (SMAG parameter) without changing the Design Moment.


  1. Stirrups are always assumed to be 2-legged

  2. Governing density to determine Light weight or Normal Weight Concrete is 2.3 kg/sq. cm