Seismic performance assessment of RC columns with interlocking hoops

The aim of this study is to analytically assess the seismic performance of reinforced concrete (RC) columns with interlocking hoops using a novel damage index, and to provide data for developing next generation seismic design criteria. Interlocking hoops are used in rectangular or non-circular columns, the splices shall be located in the column interior. Seismic performance of RC columns is controlled by the level of confinement provided by transverse steel. Interlocking hoops are commonly used in RC columns because they can provide more effective confinement than rectangular hoops. Three RC interlocking columns were tested under a constant axial load and a cyclically reversed horizontal load. A computer program, Reinforced Concrete Analysis in Higher Evaluation System Technology (RCAHEST), is used to analyze RC structures. Novel damage indices aim to provide a means of numerically quantifying the performance level in RC columns with interlocking hoops sustained under earthquake loading. The proposed numerical method for the seismic performance assessment of interlocking columns is verified by comparison with the experimental results.