I. Current introduction of riverdamming construction both home and abroad

 River damming construction is an importantpart of river construction system. The forms of dammingconstruction are mainly water dams and water gate. In small andmedium rivers, the mostly applied are water gate and water dam.
But with the rapid development of small hydropower stations in ourcountry and the ever increasing of city river renovation projects,the application scope of rubber dam is expanding. And with that,many problems have emerged, such as the impact and abrasion offloaters to rubber dam during flood season, and the applicationlimit in mountainous rivers where there is more sand and floaters.The development of small hydropower stations now has stricterrequirement for rubber dam height. Yet the maximum height of rubberdam can only be less than 6 m, which cannot satisfy the demand ofsmall hydropower stations. On the other side, small hydropowerstations mainly generate power during rain season and gain profit,but the rubber dam administration requires it to sink before theflood arrival. So it is urgent to develop a pier-less,non-water-damming, low-investment new dam with the advantages ofrubber dam while not restricted by geographical and climateconditions.    
 Tiansheng company invested large amount of money , analyzedand summarized water damming construction ‘s advantage and weakpoint, after three years, it has developed a pier-less proneablesteel gate.

II. Performance Comparation of HydraulicControlled Pier-less Proneable Steel Gate and traditional steelgate

1. Lifting gate:

Its advantages are that it is convenient to openand close it, safe and reliable. But it involves large investment,long building time, and long payback period. In mountainous riversof Southern China, if the river is 20 m deep, while the gate isonly 10 m high, when flood is coming, the water level is far higherthan the gate height, and it is quite possible that the trees flowndown with the flood will destroy the gate. At the same time, onepier must be set up in the span of two gates. If the river is wide,more piers are needed. This way water will be seriously blocked,which will affect flood discharge.

2. Hydraulic controlled pier-less proneablesteel gate

Hydraulic controlled pier-less proneable steel gatewas developed based on rubber dam and traditional steel gate. Ithas the following characteristics:

2.1  Small investment: Hydraulic controlledpier-less proneable steel gate doesn’t need piers and there is noconstruction on river. So it can save investment by 20-25% comparedwith traditional steel gate

2.2 Safe and reliable: Each time after the steelgate completes its rising and descending, the movement piston fullywithdraws into the hydraulic oil cylinder, which can effectivelyprotect the piston from rusting and prolong the life of drivingsystem. It won’t vibrate because of unstable water flow. It canfully prone to the bottom because there is no pier. The gate won’tbe destroyed because of earthquake, floaters and humanactivities.
2.3  Convenient maintenance and repair: Because when the gateis working, the driving system and the gate panel are separated, soit is convenient to maintain and repair the oil cylinder andslideway, and that will not affect the working of the gate.
2.4 Wide application scope: Hydraulic controlled pier-lessproneable steel gate, like rubber gate, doesn’t need piers and canfully prone to the bottom without blocking of water. It is notrestricted by river width and limit of geographical and climateconditions, and suitable for any river style. There is no need tomake any alteration to the riverway.
2.5 Quick installation speed, short construction period and smallinvestment
2.6. Short gate sinking time: It only takes 20-30 minutes for thisnew type of gate to fully sink.
2.7  The water retaining height can be adjusted at shorttime.
2.8 The building height of steel gate can be 4-14 m, and top watersurpassing height is 1-1.5m.
2.9 Its normal service life is 30-50 years.