ABSTRACT
This study presents a numerical study on the behavior of hybrid DSTCs under close-in blast loading. Numerical models of hybrid DSTCs were developed and validated. Afterwards, detailed numerical simulations were conducted to investigate the influences of different parameters on the behavior of hybrid DSTCs under blast loading. The mid-span deflection-time history were recorded and analyzed. The numerical simulation results indicate that the inner steel tube plays a key role in resisting the blast loading, while the contribution from outer FRP tube is less significant. Increasing the inner steel tube thickness and hollowness ratio can lead to a decrease of the maximum deflection of hybrid DSTCs. Under a lower axial load level, the maximum deflection will not increase with the increase of axial load. The influences of concrete strength and outer FRP tube thickness are insignificant.
