Gate for free spillway weirs

Abstract

A gate is provided with a barrier capable of retaining water with a central barrier wall that is inclined in a direction away from the water, a bottom structure beneath the water that is capable of delimiting by a weir a bottom chamber filled with air and holding the barrier in its water retaining position by the water pressure exercised on said bottom structure, and an inlet extending beyond the retaining level of the barrier with an upper opening that allows water to flood the bottom chamber so as to offset the water pressure on the bottom structure and thereby allow a tipping of the gate, wherein a wall structure forms a wall chamber on the central barrier wall, wherein the wall chamber is capable of being flooded so as to assist the tipping of the gate.

1 . A gate for free spillway weirs, comprising:
 a barrier capable of retaining a body of water at a predetermined retaining level with a central barrier wall that is inclined in a direction away from the body of water;   a bottom structure beneath the body of water that is capable of delimiting by a weir a bottom chamber filled with air and holding the barrier in its water retaining position by the water pressure exercised on said bottom structure; and   an inlet extending beyond the retaining level of the barrier with an upper opening beneath a predetermined flood level that allows water to flood the bottom chamber so as to offset the water pressure on the bottom structure and thereby allow a tipping of the gate; a and a wall structure forming a wall chamber on the central barrier wall, wherein the wall chamber is capable of being flooded so as to assist the tipping of the gate   wherein the inlet is integral with the wall structure and leading directly to the wall chamber.   
     
     
         2 . A gate according to  claim 1 , wherein the wall chamber is capable of being flooded in association with the bottom chamber. 
     
     
         3 . A gate according to  claim 1 , wherein the gate is capable of tipping when flood water has filled the wall chamber to at least a predetermined level.  
     
     
         4 . A gate according to  claim 1 , wherein the inlet is capable of filling the wall chamber and then the bottom chamber. 
     
     
         5 . A gate according to  claim 1 , wherein a partitioning structure divides the space within the wall structure into the wall chamber and flow-through means leading to the bottom chamber. 
     
     
         6 . A gate according to  claim 5 , wherein the partitioning structure is a partitioning wall extending upwards inside the wall structure. 
     
     
         7 . A gate according to  claim 1 , wherein the wall structure extends from the top of the central barrier wall in a direction towards the bottom chamber. 
     
     
         8 . A gate according to  claim 1 , wherein the wall structure extends substantially along the entire central barrier wall. 
     
     
         9 . A gate according to  claim 1 , wherein the wall chamber extends substantially in parallel to the central barrier wall. 
     
     
         10 . A gate according to  claim 1 , wherein the inlet is integral with the wall structure. 
     
     
         11 . A gate according to  claim 1 , wherein the wall structure is integral with the bottom structure.  
     
     
         12 . A gate according to  claim 11 , wherein a top plate of the bottom chamber constitutes a bottom of the wall chamber. 
     
     
         13 . A gate according to  claim 12 , wherein the bottom chamber is capable of being filled with water from the wall chamber through a hole in the top plate. 
     
     
         14 . A gate according to  claim 1 , wherein the wall chamber has a drain hole that is capable of releasing water in case of rain, spindrift or wave. 
     
     
         15 . A gate according to  claim 14 , wherein the bottom chamber has a drain hole that is capable of releasing water to the outside of the gate away from the body of water with a significantly lower maximum water throughput than the water throughput for flooding the wall chamber and the bottom chamber, and wherein the section of the drain hole of the wall chamber is smaller than the section of the drain hole of the bottom chamber.