Longshore drift collection device and drift sand collection method

摘要

PROBLEM TO BE SOLVED: To accurately grasp the movement of earth and sand under the action of a tsunami. SOLUTION: A bottomed tubular body 5 having a drift sand collection port 3 at the upper end and accumulating invading drift sand 4 inside, and a sand drift collection port 3 of the tubular body 5 in a standby state are closed, and a cylinder is used when submerged. It is a drifting sand drifting device provided with a cap 6 that deviates from the main body 5 and opens the drifting sand drifting port 3 into the water, and the drifting sand drifting device is installed upright at a drifting sand drift measurement point 2 where an invasion of a tsunami is predicted. , The cap 6 that closes the drift sand collection port 3 provided at the upper end of the tubular main body 5 is removed by the buoyancy force at the time of submersion or the force received from the water flow to open the drift sand collection port, and the drift sand 4 that is rolled up and moved by the tsunami is removed. It is collected by sedimenting and accumulating in the tubular body 5. [Selection diagram] Fig. 1