Experimental and numerical study on dynamic behaviour of circular steel tubes under repeated transverse impact

Offshore platforms and large-span space constructions often employ circular steel tubes, which are susceptible to significant damage from repeated impact events. This study conducts a series of repetitive transverse impact experiments on circular steel tubes to investigate their failure modes and dynamic responses. A numerical simulation model for circular steel tubes under repetitive transverse impact is then developed using ABAQUS/Explicit. Both test and simulation results reveal that the peak impact force increases with the number of impacts, while the duration decreases. The study further analyses the influence of thickness, span, impact kinetic energy, hammer shape, and impact position on the dynamic response of circular steel tubes. Additionally, numerical simulations explore the impact of energy distribution on tube dynamics through two transverse impacts, maintaining a constant total energy input. The findings demonstrate that energy distribution significantly affects peak impact force while minimally impacting displacement and residual kinetic energy.