The blast response of sandwich composites with in-plane pre-loading

The in-plane pre-loading in the ship hull structures during their service life will likely change the dynamic behavior of these structures under transverse blast loading. In the present study, the dynamic behavior of E-glass Vinyl Ester composite face sheet / foam core sandwich panels with in-plane pre-loading is investigated under shock wave loading. A special test fixture was designed which enables the application of uni-axial in-plane compressive loading when the panels are subjected to transverse blast loading. Blast tests are carried out under two levels of pre-loading and with no pre-loading using a shock tube apparatus. A high-speed side-view camera system and a high-speed back-view Digital Image Correlation (DIC) system are utilized to acquire the real time deformation of the sandwich panels. The results show that the in-plane pre-loading induced buckling and failure in the front face sheet. This mechanism greatly reduced the blast resistance of the sandwich composites. The back face deflections, back face in-plane strains, and mitigated energies were also experimentally quantified. ©2010 Society for Experimental Mechanics Inc