Damage analysis of RC panels subjected to shock wave and bubble pulse in underwater explosion

This study investigates the dynamic response and damage behavior of air-backed reinforced concrete (RC) panels subjected to shock waves and bubble pulse loads resulted from underwater explosion . Underwater explosion tests were conducted on three air-backed RC panels under various TNT charges to obtain the test data and different damage modes. The experimental results revealed that the damage in RC panels due to an underwater explosion was determined by both the shock wave and bubble pulse loads. When the scaled distance was 2.15 m/kg 1/3 , the shock wave and bubble pulse caused minor damage in the RC panel. As the scaled distance decreased, the plastic damage to the panel under the shock wave increased, and the bubble pulse caused significant secondary damage. A finite element numerical model was also developed in LS-DYNA to simulate the damage behavior of RC panels caused by both shock wave and bubble pulse loads. The numerical model results demonstrated good agreement with the test data. With the validated numerical model, further discussion on the underwater explosion induced panel failure was made, and the effect of air-backed and water-backed conditions on the damage in the RC panels against UNDEX was examined. • Underwater non-contact explosion tests were conducted on the air-backed RC panels. • FE numerical model reproduced the underwater explosion tests of three RC panels. • Damage in RC panels owing to both shock wave and bubble pulse loads during underwater explosions was analyzed. • Effect of air-backed and water-backed condition on RC panels under identical underwater explosions was examined.