On the pacifying influence of an elastomeric foam core on the failure mechanism of sandwich composites with various skin layups

The selection of a crashworthy core for sandwich composite construction has been aimed pursued in various applications. In this article, the response of sandwich beams consisting of elastomeric foam core and laminated fibre-reinforced skins with various layup sequences hereafter referred to as (EFCS) beams is investigated experimentally and numerically. This sandwich configuration provides several advantages for structural applications since the conventionally used rigid foam cores have relatively low crushing strength. The incorporation of the elastomeric foam has been found to enhance the post-failure stability and residual strength/crashworthiness of sandwich composite beams due to the pacifying influence of the core on the failure mechanism, which was further examined by numerical simulations. Both the hyperelasticity of the foam core and the progressive damage of the composite skins were accounted for in the numerical simulation. The efficiency of EFCS beams was established by comparing their performance to their laminated composite counterparts. The results evidence the promising performance of EFCS beams, especially in the context of their residual strength, which could be as high as 70% of their ultimate strength, as well as their enhancing energy absorption capacity. Furthermore, the performances of EFCS beams with angle-ply laminated skins were also examined numerically. The results reflect more advantage of using laminated skins with some specific fibre orientations.