Experimental investigation on the dynamic response of half steel-concrete composite slabs under low-velocity impact.

• The low-velocity drop hammer impact tests of five HSC specimens are conducted. • Five failure modes are proposed. • The impact process of HSC specimens is divided into 5 stages. • Static loading tests are implemented on HSC specimens to analyze structural residual bearing capacity. • Comparisons of dynamic response between HSC and SC slabs are made. The current research on the dynamic response of half steel–concrete (HSC) composite slabs is not only limited but also primarily concentrated on high-velocity impacts. This study investigates the dynamic response of such structures by examining failure modes, impact resistance mechanisms, and energy dissipation under low-velocity impacts through drop hammer impact tests conducted on five HSC specimens. In addition, the variation of the out-of-plane residual bearing capacity with the damage degree of specimens and impact energy is analyzed using static loading tests. Finally, the dynamic response differences between half steel–concrete slabs and steel–concrete (SC) slabs are analyzed by comparing multiple indicators. The results indicate that HSC slabs exhibit five distinct failure modes when subjected to low-velocity impact within a range of 3.13–7.00 m/s. Additionally, five stages of the dynamic response process of the HSC slabs are proposed. Moreover, the bottom steel plate plays a crucial role in retaining structural out-of-plane residual bearing capacity. Furthermore, compared with the SC structure, the HSC slab is capable of absorbing input impact energy within a much smaller displacement. [ABSTRACT FROM AUTHOR]