Numerical analysis of honeycomb sandwich panels under blast load

Abstract

When subjected to severe loadings, critical military and civilian structures must be able to withstand and maintain their functionality (e.g., impact, blast, thermal shock, etc). Sandwich panels with a low-density core have showed immense potential for devising shock-resistant structures in this context. Due to their excellent energy absorption, lightweight, and high specific stiffness, sandwich constructions with a light core have gained popularity. They are used mainly in aircraft and defence applications. Hence, understanding the behaviour of blast loaded sandwich structures is essential for the successful protection of human life and property. However, conducting an experimental analysis is a costly and time-consuming exercise with an additional risk to human safety. Therefore, numerical analysis is a much better alternative. In this research work, finite element (FE) analysis software ABAQUS/CAE has been used to study the behaviour of metallic honeycomb sandwich panels with squared, hexagonal and circular cores when subjected to blast loads of different kilograms of trinitrotoluene (TNT). The results of the FE modelling for square-core honeycomb sandwich panels were validated by comparing them to existing experimental data available in the literature. The effect of aluminium foam on front face deflection and energy absorption was also investigated. It was found that panels with circular core gave the best results as compared to hexagonal and square cores. After addition of foam, it was observed that the front plate deflection reduced for all core types. Also, a relation was observed between the order of deformation and plastic energy dissipation.