Stress Analysis Of Gate Under Flow-induced Vibration

Steel gate is a important part of the hydraulic structure. In the course of the destruction of the gate , the vibration of the gate often occurs in the following situation: when the gate is being opened or closed or part-closed. So how to solve the flow-induced vibration response and the dynamic characteristic ,has been the most important problems that should be solved in the design of gate.Fristly, this paper has investigated and analyzed the vibration situation of gate widely and thoroughly, the reason of gate vibration and the corresponding solution are introduced , the active method to analyze the gate vibration characteristic are introduced , and their merits and faults are analyzed. Then this paper introduces the principle and method of finite element dynamic analysis of spatial composite structure like gate. On these basis, this paper use attached mass that is the most active method to consider the fluid-solid interaction of gate and water, and the direct filter frequency method is used to solve dynamic characteristic, and the dynamic characteristic both in air and water are analyzed and compared, the corresponding results are given.The active methods of dynamic characteristic can't give occurrence of the flow-induced vibration response., In the hydraulic model experiment, the fluctuating pressure under all operating mode is measured, which is spectrum analyzed in this paper , and The time-space correlation of and the difference in each frequency of fluctuating pressure are considered, then turn the measured fluctuating pressure as the load in the FEM analysis, and use the random vibration method to calculate the flow-induced vibration response of the gate . So a method that combining the model experiment and numerical computation are discussed in this paper. The flow-induced vibration response of the plane recumbent gate in ShangHai qingshui river is computed in this method, and the result is reasonable and credibility, this method can be extend to compute the other hydraulic structures like overfall dam, guide wall, gate pier and so on, which is under fluctuating pressure.The plane recumbent gate is a new kind of gate ,after comparing with some other active gates, it can be popularized in the city river.