Research in damage characteristic of caisson gravity wharf subjected to underwater contact and near-field explosion

In order to investigate the damage mechanism and load characteristics of caisson wharf subject to underwater contact and near-field explosion, finite element numerical simulation verified by the experimental results was conducted based on the caisson wharf model test. This analysis delved into the shock wave propagation and attenuation within the caisson wharf, as well as the destruction process and damage mechanisms of the caisson wharf. The results shows that the damage areas and characteristics of the caisson wharf are largely consistent under both underwater contact and near-field explosion. The damage degree decreases as the charge distance increases. The primary destruction areas are blasting wall and the slab near explosive, and the side walls and internal partitions of the caisson wharf are relatively minor damage, the damage characteristics of caisson wharf is primarily shaped during the underwater explosion shockwave phase, which takes approximately twice the duration of the shockwave propagation through the caisson wharf. Additionally, shockwaves within the caisson wharf subjected to underwater contact and near-field explosions undergo reflection and transmission at the interfaces between the partitions and fillings within the compartments. Shock wave produces different load variation patterns due to the different propagation media. The blasting wall and cabin are subjected to significant loads, and the shock wave load rapidly decays within caisson wharf.