US Patent 10174474 Movable tsunami buffer dam

A movable tsunami buffer dam has a unit configured such that a plurality of separate units, each of which having a shape in which a frame made of a light material is sandwiched by a pair of plates made of a light material, is stacked with said plates disposed in a pile; and a locking member for locking said unit to a ground surface such that said unit can rise up from said ground surface and collapse onto said ground surface. The separate units has a structure in which water from a tsunami can advance into a space formed between said plates by said frame.