ACI 421.1R-20 (IN-LB, SI) PDF Download

ACI 421.1R-20, titled "Guide for Shear Reinforcement for Slabs," provides guidance on the design and use of shear reinforcement for slabs to resist punching shear. The standard acknowledges that punching shear in slabs can be effectively mitigated by using vertical rods that are mechanically anchored at the top and bottom of the slabs.

The document references ACI 318, which sets out the fundamental principles of design for slab shear reinforcement and specifically mentions the use of stirrups and headed studs. ACI 421.1R-20 serves as a supplementary guide that reviews the available types of shear reinforcement and provides recommendations for their design.

The guide also includes numerical examples to illustrate the application of the recommendations. These examples help engineers and designers better understand the practical implementation of shear reinforcement for slabs and assist in achieving safe and efficient designs.