Experimental and numerical studies on steel-polyurethane foam-steel–concrete-steel panel under impact loading by a hemispherical head

This paper presents a study on the low-velocity impact response of a new steel-polyurethane foam-steel–concrete-steel (SPUFSCS) panel. The SPUFSCS composite panel consisted of a steel faceplate and polyurethane foam (PUF) with a density of 193 kg/m³ that were attached to the front of the traditional steel–concrete-steel (SCS) panel. Low-velocity impact tests on the SPUFSCS panels were conducted by employing an instrumented drop hammer impact test system, and the failure modes of the SPUFSCS panels were found to consist of local indentation and global deformation. The impact process of the panels can be divided into three stages: PUF crushing, loading, and unloading. The impact force, displacement histories, and permanent deformation of the SPUFSCS panels were recorded and discussed in detail. The effects of concrete thickness and ratio of the thickness of the middle plate to that of the bottom plate on the impact responses of the SPUFSCS panels were experimentally studied. The finite element method was employed to predict the behavior of the SPUFSCS panel under impact loading, and good agreement was observed between the experimental and numerical results. Moreover, a parametric study was conducted to reveal the influence of the thickness of the PUF and top steel plate on the dynamic response of the SPUFSCS composite panels.