Theoretical modeling of steel reinforced ECC column under eccentric compressive loading

Abstract

Fiber reinforced cementitious composites (ECC) are a class of advanced composites with strain hardening and multiple cracking behaviors. Substitution of concrete with ECC can significantly improve the seismic resistance and durability of the infrastructures. In this paper, it is proposed to use ECC as the matrix of frame columns for improving its load carrying capacity, ductility, and avoiding the brittleness of concrete. Based on the assumption of plane remaining plane and constitutive models of materials, theoretical models for calculating the load-carrying capacity of the steel reinforced ECC columns under small and large eccentric compression are proposed. With the parameters of the constitutive models from the existing experimental data, the relationship between ultimate axial load and moment capacities is also derived with the proposed models. To verify the validity of the proposed theoretical models, finite element analysis with the software of ATENA is conducted to simulate the mechanical behavior of the steel reinforced ECC columns under eccentric compressive loading. The calculation results from the theoretical models show good consistency with the simulated results, indicating that the proposed models are feasible and reliable for design. Finally, based on the theoretical models, the effect of the ultimate tensile strain and compressive strength of ECC, longitudinal reinforcement ratio on the load carrying capacity of the steel reinforced ECC column are comprehensively studied.