Three-dimensional analysis of punching in reinforced concrete slabs via the finite element method

Abstract

This work intends to perform a three-dimensional nonlinear analysis of punching in reinforced concrete slabs, with the Finite Element Method (FEM), using new numeric techniques to consider the interaction between the steel bars and the concrete, as well as the nonlinear behavior of these individual components. The strategy to represent the reinforced concrete consists in an independent generation of the finite elements meshes of the concrete and the reinforcement, which are then coupled with the use of Finite Coupling Elements (FCEs). The concrete matrix is modeled with tetrahedral finite elements and it's behavior is simulated using a continuum damage model. The reinforcement is modeled using unidimensional finite elements (truss elements) with a uniaxial, linear elastic perfectly plastic constitutive relation. The loss of adherence between the reinforcement and the concrete is represented by a damage model which allows the displacement between the steel bars and the concrete matrix only in the reinforcement's longitudinal direction. This study aims to validate this new modeling strategy through numerical prediction of different tests of reinforced concrete slabs, with and without transverse reinforcement, using a computational program developed by the Unesp's research group. The predictions will be compared with results of experimental tests and obtained with other models found in the literature. (AU)