Research On Gas-filled Seal Of Super-high Head Gate In High-cold Region

With the development of Hydraulic and Hydro-Power Engineering in China，a batch ofsuper-high dams which are more than200m will be built before2020years so as toimplement the synthetic exploitation and utilization of water resources.when dams are built,we will face the problem of discharge of hydraulic engineering, Especially some dams whichhave bottom radial gates, when flood discharge developed to a certain degree, bottom radialgate is closed for utilizable benefit.this situation how closed gates safely will be faced.Gas-filled seal be installed on high head gate normally, the design selected water aspressure-filled process generally.the advantage is water can be used as the pressure. Due tothe particularity of low temperature environment, the seal will failure due to freezing, whichapplication is restricted. When the water level range substantially and the sediment and dirt islarge,it is difficult to reservoir water level is used as the pressure; In addition the pressurizedunloading soon, the pressure control hardly, So the compressed air is considered aspressurized medium, because of good compressibility and nerviness, maintaining a constantpressure steadily more important,the seal is not frozen; But because the air molecules is lessthan the water molecules, the use of air is easy to leak, so add air bags in the back pressurechamber usually. But this kind of project is applied in the low water head gate only, whichare relatively uncommon in high water head gate, a separate design requiring.This work mainly for the following:1: Hyperelasticity of rubber waterstop material in gates plays a decisive role in numericalanalysis. The mechanical behaviour of a vulcanized rubber is studied in this paper by auniaxial tensile test, biaxial tensile test and pure shear test. A set of nominal stress—straincurves for different strain rates is obtained.2:A systematic comparison and analysis in general rubber constitutive models isperformed. In the case of complete experimental data or incomplete experimental data,corresponding optimal constitutive mode is given. By the finite element calculation ofwaterstop around bottom outlet, different stress-relaxation time is given by adopting differentviscoelastic constitutive models. Compared with the real situation, Burgers constitutive mode is recommended to use. The implications for design and production for waterstop in practiceare substantial.3: Aimed at the existing problems of gas filled seal around super-high head gate inhigh-cold region, a new gas-filled telescopic seal is proposed, different materials are arrangedin corresponding section. Considering that the rubber material is a super-elastic,incompressible and large deformation, nonlinear finite element analysis of gas-filled seal insuper-high head gate under the most unfavorable conditions is executed. The new seal cansolve the present problem. The rubber material stress is less than the permissible value and onthat premise, satisfying effect in section optimization is obtained by optimum design. Theresults can provide valuable reference for the design of the section model of gas-filled seal insuper-head gate.4: Based on the fluid-structure interaction theory, The fluid dynamic analysis was carriedout on the water seal, The flow regime and water pressure between the cover plate and thegate panel and the stress state on the water seal head was preliminary analyzed...