Cyclic performance of non-ductile reinforced concrete columns retrofitted by partial steel plate jacketing: Experiment and numerical analysis

This paper investigates the strengthening of non-ductile reinforced concrete (RC) columns using partial steel-plate jacketing to enhance ductile capacity. Quasi-static cyclic loading tests were conducted on three rectangular RC columns with varying shear-span-to-depth ratios, evaluating the effectiveness of steel-plate jacketing. Results show improved ductile flexural response, high drift capacity, and maintained gravity-loading capacity under high lateral displacements. A numerical investigation, adopting a multi-spring fiber section model, predicted cyclic lateral strength, drift ratio, and failure mode, accurately simulating reinforcement behavior and capturing the shear-strength enhancement due to steel-plate jacketing. Numerical results demonstrated good agreement with experimental findings. Based on these outcomes, a simple design procedure for retrofitted concrete columns, applicable to design engineers, has been developed and reported in this paper. This study contributes valuable insights into the practical applications of steel-plate jacketing for non-ductile RC column retrofitting, offering a comprehensive approach to predicting their seismic performance.