Experimental Studies on the Backbone Curves of Reinforced Concrete Columns with Light Transverse Reinforcement

Abstract

This paper presents the investigations carried out on the backbone curves of reinforced concrete (RC) columns with light transverse reinforcement. An experimental program consisting of five half-scale RC columns with light transverse reinforcement was carried out. The specimens are tested to the point of axial failure to obtain the backbone curves of such columns. Quasi-static cyclic loading simulating earthquake actions is applied. The backbone curves obtained from the tested specimens are then compared with the existing seismic assessment guidelines. The test results indicate that the initial column stiffness and ultimate displacements (displacements at axial failure) are overestimated and underestimated by some guidelines and provisions. The existing initial stiffness and ultimate displacement models are briefly reviewed and compared with the experimental results. The results show that the existing initial stiffness and ultimate displacement models produced better results than the existing seismic assessment guidelines.