Five types of different shear reinforcement, namely single-bend, U-stirrup, double-bend, shear stud, and T-headed shear reinforcement are evaluated numerically. Emphasis is placed on the evaluation of their contribution to the punching shear capacity of high-strength concrete plates. The numerical investigation was conducted by using finite element analysis. The finite element analysis reported here is an application of the nonlinear analysis of reinforced concrete structures using three-dimensional solid finite elements. The purpose of this application is to demonstrate that three-dimensional elements represent a way to model out-of-plane shear reinforcement in the slab. Hence, the three-dimensional 20-node brick element with 2 x 2 x 2 Gaussian integration rule over the element faces and a plasticity-based concrete model were employed in a finite element program.
Single-bend and double-bend shear reinforcements were modeled with the smeared layer method, while the U-stirrup, shear stud, and T-headed shear reinforcement were depicted individually in the mesh. Reasonable agreement has been obtained between the numerically predicted behavior and experimental test results. Finite element analysis confirmed the experimental test results, that the double-bend, shear stud, and T-headed reinforcements are the most efficient types of shear reinforcement, and the U-stirrup is the least effective type of shear reinforcement. Transverse shear stress was evaluated by the finite element analysis in terms of shear stress distribution, and compared with the ultimate punching shear resistance specified by the ACI 318 design code.