Dynamic Pressure to Waterproof Sheet Placed in the Backfill Region of a Caisson-Type Bulkhead for Waste Disposal

In the caisson-type bulkhead sitting on the rubble mound with a waterproof structure using a waterproof sheet, the wave pressure transmitted through the mound, the backfill and the seabed will always act on the waterproof sheet. In order to prevent the sheet from being lifted up and ruptured by the pressure, weighting materials are usually placed on the waterproof sheet as a weight. When we design the cross section of weighting materials, it is important to appropriately evaluate the wave pressure acting on the waterproof sheet as an external force. However, few studies have been conducted on wave pressure characteristics, and there are many unknowns. Therefore, in this study, we performed a hydraulic model experiment. We analyzed this numerically, using the numerical wave flume to clarify the characteristics of the wave pressure acting on the waterproof sheet. Through this study, we propose a simple method to calculate wave pressures.