The material structure is composed of a panel, a reinforcing rib and a restraining belt. Panel material selection of thick 12mm above the high strength structural steel, meet the water welding. Each unit length 5m, the unit uses the high strength rubber compound belt soft connection. The gate rises with the horizontal plane at a certain angle, make sure the door body structure by the weight can be lodging. In order to better protect the airbag in the lodging case, gate board design has a certain radian. When in normal use, the pneumatic shield rubber dam allows the top overflow to form a water body landscape. In order to prevent the downstream water level is high or under the action of wind gate upstream dumping, the downstream side door body is provided with a folding safety stopband, synthetic rubber material with high strength in the stopband.