Influence of Multi-Layer Core on the Blast Response of Composite Sandwich Cylinders

Abstract

The influence of a multi-layer core on the blast response of composite sandwich cylinders under internal explosive loading was investigated. Experiments were conducted first to obtain the fundamental deformation and failure patterns of composite cylinders with uniform, double-layer, and triple-layer profile cores. They were compared with the finite element model for prediction with good agreement. The mechanisms of energy absorption and deformation of a composite sandwich were explored by parametric analysis. Experimental results indicated that compaction wave in a double-layer core was initiated from the inner face sheet and then propagated to the outer face sheet when the gradient was positive; however, the core densification started at the inner surfaces of both layers and propagated to the outer face sheet together. The maximum radial deflection decreased with increasing face sheet thickness or decreasing blast loading. The percentage of energy absorbed by the core increased with decreasing face sheet thickness or increasing blast loading. This study revealed a possibility to reduce the maximum deflection (same structural mass and same energy absorption) for the sandwich cylinders by using a proper core distribution.