Experimental and modeling investigations of the behaviors of syntactic foam sandwich panels with lattice webs under crushing loads

Abstract

Abstract The composite sandwich structures with foam core and fiber-reinforced polymer skin are prone to damage under local impact. The mechanical behavior of sandwich panels (glass fiber-reinforced polymer [GFRP] skin reinforced with lattice webs and syntactic foams core) is studied under crushing load. The crushing behavior, failure modes, and energy absorption are correlated with the number of GFRP layers in facesheets and webs, fiber volume fractions of facesheets in both longitudinal and transverse directions, and density and thickness of syntactic foam. The test results revealed that increasing the number of FRP layers of lattice webs was an effective way to enhance the energy absorption of sandwich panels without remarkable increase in the peak load. Moreover, a three-dimensional finite-element (FE) model was developed to simulate the mechanical behavior of the syntactic foam sandwich panels, and the numerical results were compared with the experimental results. Then, the verified FE model was applied to conduct extensive parametric studies. Finally, based on experimental and numerical results, the optimal design of syntactic foam sandwich structures as energy absorption members was obtained. This study provides theoretical basis and design reference of a novel syntactic foam sandwich structure for applications in bridge decks, ship decks, carriages, airframes, wall panels, anticollision guard rails and bumpers, and railway sleepers.