Development of a numerical model for RC columns considering seismic dynamic effect and different failure modes

Abstract

Due to the strain rate sensitivity of concrete and reinforcing steel materials, the mechanical behaviors of RC column members subjected to dynamic loading are significantly different from those measured under static loading, i.e. the dynamic effect. In this paper, a numerical model capable of reflecting the dynamic effect and different failure modes is innovatively developed for RC columns by adding the modified sub-elements to the fiber beam-column element on the OpenSees platform. The methods for considering the dynamic effect on multiple deformation components, including the flexural, shear and bond-slip deformations are put forward. Moreover, the accuracy and effectiveness of the proposed model are verified by comparing the numerical and experimental hysteretic curve and deformation components of RC columns under different failure modes and loading rates. By analyzing the simulated results of hysteretic behavior using the modified and unmodified model, the necessity of dynamic modification to the deformation sub-elements are highlighted. It is revealed that the proposed numerical model can provide reasonable predicted results to the dynamic hysteretic behavior and failure mode of RC column members, and can be further applied to improve the accuracy of seismic performance assessment for RC structures.