Low velocity impact performance of curved steel-concrete-steel sandwich shells with bolt connectors

Abstract

Abstract The low velocity impact performance of curved steel-concrete-steel (CSCS) sandwich shells with bolt connectors subjected to a hemi-spherical head drop hammer was investigated in this paper. Experimental results including impact force history, displacement history and permanent deformation were analyzed to reveal the influences of concrete core and steel plate thickness as well as shear connectors’ spacing on the impact performances of CSCS shells. The impact process consisted of three stages, i.e., inertial stage, loading stage and unloading stage. Meanwhile, three failure types were observed from the nine specimens subjected to impact load. They were plastic deformation of steel plate without fracture (Failure type I), fracture of steel plate (Failure type II) and penetration of steel plate (Failure type III). The presence of bolt connectors was proven to be an effective way to prevent the detachment of steel plates from concrete core. Moreover, finite element (FE) method was used to simulate the CSCS shells subjected to impact load. The accuracy of the FE model was verified by comparing the impact load history, displacement history and failure type from FE simulations with test results. It turned out that concrete core was the main part to dissipate impact energy, followed by top steel plate and bottom steel plate.