| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a door body structure enabling a door body to rise even if it is damaged due to vehicle passage in its fallen state or collision of a fallen object, and capable of maintaining the rising state even when the door body in the rising state is damaged due to the water pressure of a tsunami or high tide. <P>SOLUTION: A door body 2 of a floating body type flap gate 1, which is installed at an opening or a gateway, and of which tip side 2b rises and swings around a base end side 2a within a plane in the height direction in a water inflow direction in order to block the opening or the gateway when water flows in, is formed of a tabular hard polyurethane foam 4. As a buoyancy required for rising is generated by the tabular hard polyurethane foam, the door body 2 can rise without rapid decrease of the buoyancy even if the tabular hard polyurethane foam is damaged due to wheel load of a vehicle running on the door body in the fallen state. Moreover, the rising state can be maintained without falling even if the tabular hard polyurethane foam is damaged due to the water pressure of a tsunami or high tide. <P>COPYRIGHT: (C)2013,JPO&INPIT |
