| With home and abroad some hydraulic-gates of opening-process appearing hoistoverload, deadlocking, or even destroy of the accidents, the gate run security is paidmore and more attention. At the design stage of a reasonable estimate of the gateopening and closing force is related to the gate of the normal operation of importantfactors. At present, our current norms " Hydraulic and hydroelectric engineeringspecification for design of steel gate "(SL74-95) gives the plane and radial gate oflifting-force formula in water. However, in actual operation, according to thespecification formula of the calculated results to select hoist capacity, it leads to manyproblems. This paper will be on these issues in-depth study, as follows:(1)According to the analysis of several domestic reservoirs of the sedimentstatistics, siltation of sediment in front of the gate will be consideration to the coarseand fine particles sediment Bingham model. In this sediment model, the contact andthe relative sliding among the coarse particles supply frictional shearing stress, andflocculation of the among fine particles supplies the limit of shear stress. in the gatesopening of the moment. These two forces together constitute the sediment criticalyield stress. And it is using a mathematical model to valid the sediment critical yieldstress calculation method. Simutaneously, considering coarse particles mode of actionto the gate panel in the siltation, this paper proposes two reduced-siltation-effect ofhydraulic gate structures, namely: the dual-rail-inclined plane gate structure and theeccentric-hingeless radial gate structure.(2) Firstly, combined with Kelvin-oscillator-model, the equivalent-damping,ephemeral-temperature and the elastoplastic criterion of frictional contact surfaces,this paper proposes the coefficient of sliding friction. And it applies the existingliterature data to valid the friction coefficient calculation method. Secondly, the scrollwheel which is in orbit simplifies into a cylinder with infinite half-plane contactproblem. It proposes wheel-frictional-resistance-arm calculation method. And itapplies mathematical model to valid wheel-frictional-resistance-arm calculationmethod. The last one, by changing the mode of action of the lubricant inself-lubricating bearings, this paper proposes two self-lubricating bearing structureswhich are able to provide "active lubrication".(3) Based on the understanding of the rolling bearing, in the walking support, ofthe energy consumption of the form, this paper proposes rolling-frictional–resistance -arm calculation method. And it applies existing literature data to valid the frictional-resistance-arm calculation method.(4) The sealing rubber friction generation attributes to hysteresis deformation,adhesion effects and furrow effect of three factors. This paper proposed thecalculation method of the coefficient of sliding friction.(5)According to Bernoulli and momentum equations of the flow, this paperrespectively gives the calculation method of the under-suction and lifting forces in theopening and closing process. And it applies mathematical model to verify the abovecalculation method.(6) On the one hand, considering of the sediment dry bulk density in the frontgate, porosity of the sediment, silt sediment properties (such as: the finer sediment ofclay, fine silt, etc.), the contact area of the sediment and the gate, the sediment thelevel pressure, walking-bearing friction, under-suction and the sediment in the top ofthe door and grillage, etc, the paper proposes the lifting-force calculation method ofthe plane and radial gate in the siltation. And it uses measured-data to verify the abovecalculation method. On the other hand, based on Visual Basic program-development-platform, database, graphics processing, document generation, and simulation ofcomputer technology, this paper develops the DP-1.0design simulation platform. |
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