Numerical Analysis of Double-Leaf Composite Stiffened Door Subjected to Blast Loading

Doors are the most critical part in any structure as they may eventually fail first when subjected to extreme loads such as blasts. Blast resistant doors in a structure work as effective barriers against blast pressure thus making the entire structure safe. Accordingly, the need to provide blast resistant doors arises in important structures to endure blast pressure. Herein, the comparative performance of a three-hinged five-latched double leaf composite door subjected to blast loading is investigated using finite element analysis software LsDyna. The composite door consists of front and rear steel plates composed of armor steel and three different infill materials, i.e., polyurethane (PU) foam, aluminum syntactic foam with $200\mathrm{\mu m}$ cenosphere (Al200), or plain cement concrete (PC) are explored in this investigation. Comparative studies of these composite doors are performed by varying the thicknesses and types of infill material and blast-scaled distances. The peak deflection, permanent deflection, internal energy, and total energy are compared among the doors considered herein. Weight and cost analysis of the door are also considered to determine the most cost-effective solution. The numerical results show that the polyurethane core door illustrates better performance for 150 mm of core material. However, the plain concrete infill door and cenosphere aluminum alloy core door demonstrate enhanced performance for 100 mm core thickness at 0.15, 0.2, 0.3, and $0.4\mathrm{m}/{\mathrm{kg}}^{1/3}$ scaled distances.