Response of multi-cell steel-concrete-steel sandwich panels impacted by a hemi-spherical head: Experimental and numerical studies

In this study, a novel multi-cell steel-concrete-steel (MCSCS) sandwich panel was proposed for enhancing impact resistance of the traditional steel-concrete-steel (SCS) sandwich panel. The MCSCS sandwich panel employed stiffeners and headed studs to improve the bonding behavior between faceplates and concrete core as well as enhance its composite action and impact resistance. Impact tests were conducted on seven MCSCS panels via employing a drop weight loading system, and the influences of impact direction, spacing of headed stud and steel plate thickness on responses of MCSCS panels were investigated. Furthermore, the Finite Element (FE) model of the MCSCS panel was established, and the FE predictions were shown to be reasonable as compared to test results. Two types of failure modes of MCSCS panels under impact load were obtained via analyzing the test and FE results. In addition, based on the verified FE model, the influences of stiffeners, impact location and curvature of hammer head on impact responses of MCSCS panels were revealed via parametric studies. The results of FE simulations indicated that the impact location and curvature of hammer head had evident effect on the energy absorption and impact response of the MCSCS panel. Moreover, owing to the employment of stiffeners, the impact resistance of the MCSCS panel was evidently enhanced as compared to the traditional SCS panel.