Dynamic Response Experiment of Prefabricated Wall Panels for a Whole-Indoor Substation under Blast Loading

A novel prefabricated wall panel structure for substations was developed by integrating fiber cement board, aluminum honeycomb plate, and aluminum alloy plate. The dynamic response characteristics of the structure under explosive loads were investigated through experimental studies. The effects of overpressure loads at different explosive mass and loading distances were examined, and the impact of varying honeycomb cell sizes on structural deformation failure mode, back face deflection and strain, core compression, and fiber cement board crack distribution was analyzed. The results indicate that within a confined space, the time characteristics of explosion overpressure are similar to those in an unconfined space. The peak overpressure measured independently at the center is between 2.4 and 10.0 times that measured directly at the edge. The positive pressure duration measured independently at the center is between 0.44 and 0.71 times that measured directly at the edge. The predominant deformation mode of the structure involves front panel depression and rear panel bulging. Horizontal cracks in the front face of the fiber cement board are predominantly located near its long side boundary, while cracks in the back face are mainly distributed near its center and diagonal areas. Compared with structures featuring smaller honeycomb cell sizes, those with larger honeycomb cell sizes exhibit greater residual deflection on their back faces and longer total crack lengths in their fiber cement boards.