Author(s): Kunihiro Ogihara Of Neering
Linked Author(s):
Keywords: Gate Vibration; Wave force; Impulse force; Air cushion
Abstract: Long span gate near the river mouse is constructed for stopping the salt-water intrusion to upstream or protecting the high tide from the sea. These gates are affected the wave forces at high sea water level and are vibrating strongly in same period of wave force. Usually these gates are consisted by two coupled gates such as the lower gate, which lay on river base, and the upper gate, which is hanged by rope or hydraulic oil system. This upper gate is easily to be vibrating by coupling the bending motion and vertical motion of elongation of rope. Wave action acts on gate in two directions as vertical and horizontal, and attacking to the upper gate are very important for the vibration. The attacking forces of the wave vary by the relation of the distance between the water level and bottom skin plate of upper gate, wave height and air volume under the bottom of gate. When air flows out from the bottom part of gate, wave force act directly to gate and gate vibrates strongly. But when some air remains under the bottom part of gate, air acts as cushion and wave force is deceased.
Year: 2005