Dynamic Response of Prefabricated Wall Panels for a Whole-Indoor Substation under Blast Loading Based on Finite Element Simulation

The honeycomb core layer is light and has the advantage of high specific stiffness, specific strength and specific energy absorption. A novel prefabricated wall panel structure for substations was designed by combining fiber-reinforced concrete panels, honeycomb core layers, and aluminum alloy panels. The dynamic response of the structure under the blast load was investigated, as well as the effect of the explosive mass and the size of the honeycomb core. In this paper, a finite element model was established and compared with the experimental results, which was found to be in good agreement with each other, thus validating the model. On this basis, the effects of explosive mass and honeycomb core layer on the structural deformation failure mode, midpoint deflection of back panel and energy absorption were investigated. It is shown that the deformation pattern of the structure is mainly concave at the front and convex at the back, and the honeycomb core layer is compressed, resulting in the whole deformation. Then the fiber cement of the front panel is separated with the honeycomb core layer, and the fiber-reinforced concrete panels of the back panel have failure at the center and diagonal, and the crack expandes, and the compression of the core layer increases. It was found that for the same amount of explosion, the center deflection of the back panel of the honeycomb structure with small size was reduced by 18.5%, 17.1%, and 18.1% compared to the honeycomb structure with large size. Meanwhile, the energy absorption of the honeycomb structure with small size was increased by 7.8%, 6.7%, and 2.2% respectively compared with that of the honeycomb structure with large size. Thus, the honeycomb structure with small size has better impact resistance. Under blast load, the fiber-reinforced concrete panels on the front panel absorbs the most energy, accounting for more than 50%, followed by the honeycomb core layer, accounting for about 45%, and the back panel fiber-reinforced concrete panels absorbs less energy, and the energy absorption is within 5%.