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For most columns, minimum shear reinforcement is required where Vu > 0.5φVc. See notes at the end of this discussion for Av,min requirements of specific section types. Note that there are different equations for Av,min for non-prestressed and prestressed members, but the same equation for Av is used for both types of members (inclined stirrups may be used for non-prestressed members)Minimum transverse reinforcement is computed following section 10.6.2.2. Av minimum will always be displayed in the output whether it is required or not, however when it is not required it will not be included in the Av Required total in the output. An checkbox, under shear options, may be used to zero out minimum transverse when it is not required.
Note that there are two Vs terms used in the program, one is Vs,reqd, based on Vu-Vc, and the second is Vs,prov, based on the area of shear steel input by the user.
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