Dynamic Analysis And Optimum Study For Concrete Supporting Structure Of Power Station

The construction of pumped storage power station is stating a high developing stage with the high speed developing of the power industry in China. Running with high speed and double directions, starting with high frequency which are the characteristics of the pumped storage power station, so the vibration of the support structure in powerhouse caused by the turbine swing or the hydrodynamic pulsation should be paid more attention.This article has studied the characteristics of self-vibration for support structure in powerhouse by choosing different calculation method, has analyzed the cradle of vibration and checked for sympathetic vibration which are caused by hydrodynamic pulsation, turbine swing etc., at the same time it has calculated the dynamic response of the support structure of the turbine acted by dynamic load, the proposal of the above is founding one more reasonable and more effective dynamic analysis method for the support structure of the turbine, Zhang Hewan pumped storage power station project is taken as the sample of all above. Further it has compared the dynamic characteristics of the support structures of the turbine with Shi Sanling, Guang Zhou and Tian Huangping pumped storage power station, and has analyzed the advantages and disadvantages between them, so that we could choose the reasonable style of the structure, and find the effective measures to avoid the vibration. The main conclusion are the followings:1. The structure of the turbine foundation has been simplified to alone vibration system, the frequency of self-vibration and amplitude of vibration has been calculated accordingly in "The design criterion of hydro powerhouse", the affect by space of the structure has not been considered in the design criterion, so the difference of the rigidity between the concrete plate, post , the foundation of the generator cover, foundation of the turbine and the enwrapped concrete of the spiral case has not been considered completely, so its calculated conclusion is not the actual reflection for the complicated structure of hydro powerhouse with huge capacity. By using the calculation method of presumed statics, the calculation conclusion of dynamic response and rigidity is a little bigger than the actual situation, by using the analysis method of harmonized response, the calculation conclusion is more closed the actual situation, the above two calculation method are three way limited unit method of calculation.2. By comparing the frequency of the cradle of vibration and the powerhouse structure self-vibration, the structure design for Zhanghewan pumped storage power station is generallyreasonable, there is not possibility that the resonance happens;the analysis conclusion of dynamic response for the structure of underground power house shows that the max. Swing of the foundation of the generator did not exceed the limited value of the criterion. The design rigidity of resisting vibration of the upper and lower support of the generator meets the requirement of the manufacturer.3. The units running frequency (lower frequency mostly) is more influential among the cradles of vibration, normally the basic frequency is far away the units running frequency, the stronger structure whose self-vibration frequency will be higher, which is more helpful for making more difference between the basic frequency and the units running frequency of the combined structure;no keeping slot between two units less affect for the floor's rigidity, but it will more affect for the foundation of the generator. The thick-plate structure should be more helpful to increase the rigidity of whole structure with static load.4. Among the main effective factors of the dynamic characteristics in underground powerhouse, the effect of the restricted situation of the board is bigger than other factors, it should be used to optimize the whole dynamic characteristics for the design of avoiding vibration at the concrete structure of underground powerhouse. There are many successful sample at various projects for keeping slot between the structure of generator unit and choosing of type of the concrete plate, which is requested to compare and confirm according the actual situation of the project.