Abstract: To prevent a door body from shaking significantly when it rises. A floating body flap gate is provided which is disposed on a roadway surface in an opening; and causes a door body to rise to block the opening when water is trying to flow in from the opening by using a water pressure of the water which is trying to flow in and a buoyancy of the door body. The door body is formed with three door body blocks, which are separated in the vertical direction. These door body blocks which are separated in the vertical direction, are connected by rotation mechanisms for rotation at a specified angle within a vertical plane in a direction in which the water is trying to flow in from the opening. The door body is not subject to significant shaking, regardless of the water level at which the water tries to flow in from the opening.

Abstract: The invention is for a mooring device (11) for a flap-gate breakwater (1) having a water blocking door body (2) that pivots about a horizontal axis. The mooring device (11) comprises a mooring hook (15) that controllably engages and disengages a gate mooring member (2b) of the door body (2) during mooring and raising operations. The mooring hook (15) is operated by a control device (21), making it possible to adjust the mooring hook position in a short period of time.

Abstract: To make it possible to hold a door body in an immobilized state without oscillating when the raising operation has been completed. A raised state holding mechanism of a flap gate for a breakwater provided with a two-folding support rod which immobilizes and supports a door body the front end side of which is supported to freely rise or lower with a rotating shaft as a supporting point, and a stay which supports this and to which is attached a guide roller the movement of which is guided by a guide rail. Between a two-rod double-acting cylinder device and an oil tank there is a raising side oil supply pathway which supplies oil to a raising side oil chamber, a raising side oil discharge pathway which discharges oil from the raising side oil chamber, and a lowering side oil pathway which supplies/discharges oil to a lowering side oil chamber.

Abstract: To prevent a door body from shaking significantly when it rises. A floating body flap gate is provided which is disposed on a roadway surface in an opening; and causes a door body to rise to block the opening when water is trying to flow in from the opening by using a water pressure of the water which is trying to flow in and a buoyancy of the door body. The door body is formed with three door body blocks, which are separated in the vertical direction. These door body blocks which are separated in the vertical direction, are connected by rotation mechanisms for rotation at a specified angle within a vertical plane in a direction in which the water is trying to flow in from the opening. The door body is not subject to significant shaking, regardless of the water level at which the water tries to flow in from the opening.

Abstract: To make it possible to hold a door body in an immobilized state without oscillating when the raising operation has been completed. A raised state holding mechanism 21 of a flap gate 11 for a breakwater provided with a two-folding support rod 13 which immobilizes and supports a door body 12 the front end side of which is supported to freely rise or lower with a rotating shaft 12a as a supporting point, and a stay 17 which supports this and to which is attached a guide roller 17c the movement of which is guided by a guide rail 18. Between a two-rod double-acting cylinder device 22 and an oil tank 32 there is a raising side oil supply pathway 29 which supplies oil to a raising side oil chamber 22d, a raising side oil discharge pathway 34; which discharges oil from the raising side oil chamber 22d, and a lowering side oil pathway 37 which supplies/discharges oil to a lowering side oil chamber 22e.

Abstract: To adjust a mooring hook position in a short period of time. A mooring device 11 for a flap-gate breakwater 1. A mooring hook 15 is attached in a position to engage with a gate mooring member 2d of the torque shaft 14 which is provided in a position corresponding to a gate mooring member 2d of a gate body 2 in a mooring state. A counterweight 16 which rotates the mooring hook 15 in a direction to release engagement with the gate mooring member 2d. A rod member 17 having one end connected in a position toward the other end of a torque arm 18 with one end attached to the torque shaft 14, and having the other end of the rod member 17 having a first vertical rod 17a provided with a slot 17aa at one end and a spherical bushing 17ab at the other end, is pulled above the surface of the water via two link members 12, 13.