Enhancement in air blast mitigation performance of steel sandwich structure with efficient thin-walled honeycomb cell packing
Murlidhar Patel, Shivdayal Patel, Santhosh Kumar Kamarapu, Shivanku Chauhan, Neeraj Kumar Bhoi
Abstract
Due to air blast attacks, lots of people lost their lives or suffered from severe injuries; many buildings, infrastructures, and expensive objects were destroyed. However, efficient blast resistance structures are in major demand in the present era. Honeycomb sandwich structures are the most preferable for making protective structures against blast loads due to their outstanding energy-absorbing ability and excellent deformation resistance. The packing of honeycomb cells at constant volume significantly influences the blast resistance characteristics of the sandwich structures. Experimental evaluation of structures’ blast resistance is very costly, time-consuming, and hazardous to the environment. Hence, in this study, a sequence of explicit dynamic numerical analysis was performed to investigate the square and hexagonal packing patterns of circular honeycomb cells with vertical and horizontal arrangements impact on crashworthiness of the sandwich structures at different levels of air blast loads. The conventional weapons effect program (CONWEP) module was used to apply the air blast loads varying from 1 to 3 kg of trinitrotoluene (TNT) on the sandwich structure for a fixed stand-off distance (SoD) of 0.1 m. The rate-dependent Johnson-Cook (J-C) material model was used to obtain realistic deformations of the structures. The findings of the work represent that the horizontally arranged and hexagonal packed circular honeycomb sandwich structures provide the highest protection against blast loads due to their smallest back face deflection, uniform core crushing, and highest energy dissipation through the core at every level of air blast loadings.