Experimental and numerical study of square sandwich panels with layered-gradient foam cores to air-blast loading

摘要

The blast response of clamped sandwich panels with layered-gradient aluminium foam cores was studied experimentally and numerically. The effective blast impulse acting on specimens in ballistic pendulum tests was first calibrated, and the influences of blast impulse and core-layer arrangement on the deformation modes and shock resistance were revealed. Then, the corresponding numerical simulations were conducted. The finite element model was validated via the displacement?time curves of the ballistic pendulum system and the deformation profile and deflection response of sandwich specimens. The blast pressure, deformation process, energy absorption, strain evolution, and distribution of blast-loaded sandwich panels are discussed. The experimental and numerical results show that all the layered-gradient core sandwich panels have a weaker blast resistance capability than the ungraded sandwich panels because of the reduction in structural integrity of the specimens. For a given effective impulse, the specific energy absorption value of the positive gradient sandwich panels is the largest, followed by that of the ungraded sandwich panels, whereas that of the negative gradient sandwich panels is the lowest.