The Analysis Of Dynamic Characteristics And Aseismic Behaviors On The End Powerhouse Unit

Increasing petrochemical energy shortage, hydropower as a renewable and clean energy is catching more people's eyes. In China, the hydropower development emphasis in the southwest and the northwest region, where is a high incidence area of high-intensity earthquake. Earthquake is a sudden natural disaster, which endangering people's lives and property safety, and often brings serious losses of life and property. At present, both at home and abroad, in general, the middle unit of powerhouse has been concentrated more than the end unit, especially in the seismic properties.The end powerhouse unit is a cassette shell with one side open and other three sides closed, which is a non-symmetric space structure. Under the earthquake action, the damage of gable wall side with greater stiffness is not easily occured, but the other wall with relative less stiffness will produced torsion effect. After the dynamic characteristics and aseismic behaviors of the end powerhouse have been studied, the stiffness and mass distribution can be understood, the force weak links of the structure can be founded, and the protective measures will be carried on.In this paper, combined with a project, considered whether to set rubber bearings under roof rack, the rounded bearing model and rubber bearing model according to the actual size of the structure have been built, based on the ANSYS analysis software. In the model, the foundation was simulated by the solid elements, the wall were simulated by the shell element, the column and beam was simulated by the beam element, the links of the grid were simulated by the link element, the quality of the roof load and bridge crane were simulated by the mass element. After the dynamic characteristics and the aseismic behaviors of the two models have been calculated, conclusions were obtained as follows:(1)Dynamic characteristics of the rounded bearings model and the rubber bearings model has been calculated, the result of which has shown that after set rubber bearings, the value of each frequency became smaller in the whole, and the vibration patterns changed so much.(2)The time-history analysis method has been used to calculate the dynamic distribution coefficient of the structural. After the rubber bearings have been installed, the value of the acceleration distribution coefficient factor became bigger.(3)Under earthquake action which direction parallel to the river, the displacement, the internal force, and the stress of key parts on the rounded bearings model and the rubber bearings model have been researched, and a series of comparative data has been gotten.(4)Under earthquake action which direction transversal to the river, the effect and influence of rubber bearings to the result of displacement, internal forces, and the stress have been considered, and a series of comparative conclusion has been obtained.