Concrete behavior in steel-concrete-steel panels subjected to biaxial tension compression

Abstract

Steel-Concrete-Steel (SCS) composite wall is being used for different purposes for its improved performances. Some analytical and finite element models have been presented in the past to predict the behavior of such walls. In this paper, an attempt is made to develop an iterative membrane model to analyze SCS wall panels subjected to in-plane membrane forces in the principal directions. The model accounts for the post-cracking Poisson effects of concrete as the Zhu/Hsu ratio.Individual behaviors of concrete and steel plates in an SCS panel are studied in which confinement in principal tensile direction accompanied by negative uniaxial tensile strain in concrete is observed. To explain this behavior, a detailed perspective for uniaxial strain in principal tensile direction is proposed and the conventional stress-strain trajectory of concrete in tension is extended to incorporate any confinement developed in the concrete. Constitutive law of concrete in compression is also modified to incorporate the observed confining behavior of the concrete.