Experimental and numerical study of corrugated steel-plain concrete composite structures under contact explosions

This paper investigates the dynamic response and blast resistance of corrugated steel -plain concrete (CSPC) composite structures subjected to contact blast. A series of explosive tests were conducted to investigate the acceleration, deformation, and damage patterns of CSPC plates under varying blast loads and arrangements of shear connectors, and these findings were compared with reinforced concrete (RC) plates. The results suggested that CSPC plates exhibited superior ductility and blast resistance, and effectively mitigated concrete collapse. The CSPC slab primarily underwent elastic deformation when the TNT charge was small, with the rebound deformation of the concrete and steel plates acting as a significant mode of energy dissipation. As for larger TNT charges, the maximum deformation of the plate progressively increased, especially when exceeding 0.3 kg, the deformation rebound ratio decreased significantly, and the plastic deformation increased. For further increased explosive loads, the concrete and steel plates exhibited a pronounced strain rate effect with a slowed growth rate of deformation. By examining different configurations of shear connectors, it was discovered that the adhesive strength between concrete and steel plates was closely related to the energy dissipation mode, and the elastic recovery capability and deformation resistance of the CSPC structure significantly deteriorated when the shear connectors were shorter, sparser or thinner. A numerical model based on LS-DYNA was designed to further analyze the blast resistance characteristics of CSPC plates. An engineering collapse coefficient Kz was established to predict the failure level of the CSPC plates. This paper provides useful insights for the optimal design and damage assessment of CSPC composite structures.