CHANGE IN SAND TRANSPORT OWING TO CHANGE IN SEAPAGE FLOW DURING WAVE RUN-UP WHEN ROCKS ARE BURIED UNDER FORESHORE

Abstract

 When impermeable objects such as rocks or beach rocks are buried under the beach face, the return flow and seepage flow during wave run-up will change, causing the change in sand deposition and erosion of the foreshore. A two-dimensional movable bed experiment was carried out to investigate foreshore changes under the condition that rocks are buried under the foreshore composed of gravel, while changing the location of the model rock and the thickness of gravel layer over the rock. From the experiment of 25 cases, it was found that that the direction of the cross-shore sand transport strongly depended on the location and thickness of the gravel layer.