Study On The Reliability Of Components Of Radial Steel Gate And The Optimal Design

In this paper, the following works have been done according to the background of thearc steel gate of the Wanwanchuan hydropower station. First, a new corrosion functionis put forward and the influence of corrosion on the component and its structurereliability are analyzed based on the literature analysis and Engineering case analysis;second, The structure of the steel gate in this project is optimized；Third, under thereason of the change on the steel gate components’ size which is caused by thecorrosion, the influences on the steel gate are analyzed.The main research contents areas follows:(1)The following conclusions can be found through the analysis on the reasons ofexisting hydraulic steel gate modification. That is the main reason of the modificationcan be divided into human factors and non-human factors, when the modification is notcaused by the human factors, the corrosion is the main factor.(2)The influence on the internal corrosion of hydraulic steel gate materials isanalyzed according to the experimental analysis on the arc steel gate of theWanwanchuan hydropower station which is ran on34years. It can be proved that thechemical composition and mechanical properties of material can’t be affected by thecorrosion, and the decrease of the component force area which is caused by corrosioncan lead to the decay of steel gate structure resistance.(3)A new nonlinear corrosion function has been got by the study on the corrosionbehavior of existing hydraulic steel gate. Under this new function, the resistanceattenuation of steel gate components and the change of reliability index are restudiedwhich can guide the gate modification in time and reduce the risk of structural failure.(4)The arc gate structure is optimized by the finite element software and the methodof first-order optimization. According to the Optimization, an optimal size of thecomponents can be got, at the same time, the project investment cost and therequirement for opening and closing device can also be decreased.(5)Through the sensitivity analysis on the retrofit design of the arc steel gate ofWanwanchuan hydropower station, the following conclusion can be got: first, as themain component of steel gate, the change of the panel size is sensible to the load effect of the gate; For high steel gate, it is very sensitive to the size change of girder backflange, all this conclusions can be used to the existing hydraulic steel gate.The research of this paper has strong feasibility and practicability. The resultsprovided great reference and practical value for both maintenance renovation andoperation of the hydraulic steel gate.