Improving the Impact Resistance and Antisplash of Civil Air Defense Wall: Experiments and Finite-Element Simulation

Studying the Effects of Wave Dissipation Structure and Multiple Size Diffusion Chambers on Explosion Shock Wave Propagation

“…Table 2 and Figure 12 show that 5-5, 5-8, and 8-5 have strong shock wave suppression effects. −26.91% 500 mm × 500 mm × 200 mm 21.48% 500 mm × 800 mm × 200 mm (5)(6)(7)(8) 45.27% 800 mm × 300 mm × 200 mm (8-3)…”

“…Fire 2023, 6, x FOR PEER REVIEW 12 of 500 mm × 300 mm × 200 mm (5-3) −26.91% 500 mm × 500 mm × 200 mm 21.48% 500 mm × 800 mm × 200 mm (5)(6)(7)(8) 45.27% 800 mm × 300 mm × 200 mm (8-3) −32.60% 800 mm × 500 mm × 200 mm 28.73% Shock waves are often suppressed at 21.48%, 45.27%, and 28.73% by 500 mm × 50 mm × 200 mm, 500 mm × 800 mm × 200 mm, and 800 mm × 500 mm × 200 mm diffusio chambers, respectively. Other-sized diffusion chambers also strengthen the shock wav Utilizing a diffusion chamber that measures 500 mm × 500 mm × 200 mm by the size spe ifications of civil air defense engineering design is advised.…”

“…The reverse shock wave and the forward shock wave cancel each other out, reducing the shock wave's energy. (6) The forward and backward shock waves cancel one another to generate a shock wave-canceling plane in the middle of the explosion chamber, as shown in Figure 14f. (7) As seen in Figure 14g, the combined impact of offset, reflection, and superposition considerably reduces the shock wave.…”

“…According to the construction and support specifications, the explosion chamber's length and breadth should not exceed four times the roadway's diameter. As a result, the length, width, and height of this experiment were custom-made for explosion chambers in the following sizes: 300 mm × 300 mm × 200 mm (3-3), 300 mm × 500 mm × 200 mm (3-5), 300 mm × 800 mm × 200 mm (3)(4)(5)(6)(7)(8), 500 mm × 300 mm × 200 mm (5-3), 500 mm × 500 mm × 200 mm (5-5), 800 mm × 300 mm × 200 mm (8-3), 800 mm × 500 mm × 200 mm , and eight other sizes. To increase the viability of the numerical simulations, experimental investigations were used to validate them, and based on these studies, more research was conducted.…”

“…The first category focuses on wave-absorbing materials research. Through pendulum impact experiments and numerical simulations, Shi et al [6] investigated the mechanical response of a human defense wall sprayed with POZD material. Iqbal et al's [7] experimental investigation of the mechanical behavior of polyurea-sprayed masonry walls under blast loads revealed that energy absorption improves with coating thickness and that polyurea composites with a thickness of 6 mm can tolerate higher pressures.…”