Predictions of lateral deflection of square concrete-filled steel tube column under explosive impulse

This study investigates lateral deflection of square concrete-filled steel tube (CFST) columns under blast loads. Impulse time histories were obtained from the blast test, and lateral deflection of square CFST without axial load was predicted by using the SDOF system based on the impulse input. Intensive numerical simulations were conducted to investigate the influences of axial compression ratio and confinement coefficient on the lateral deflection of square CFST columns subjected to blast loads. A total of 168 case scenarios were studied by using LS-DYNA. With the increasing axial compression ratio, the lateral deflection decreases gradually and then in-creases sharply. The lateral defection decreases remarkably with the increase of the confinement coefficient. Based on the numerical results, a formula was proposed to predict the maximum lateral deflection of the square CFST column under blast load, and the accuracy of the formula was verified by comparing it with the blast testing results.