Modal Analysis of Hydropower House by Using Finite Element Method

In order to analyse the free vibration characteristics of hydropower house, finite element method (FEM) is used in the modal analysis. The main emphasis is placed on the problem of influencing factors of the modal analysis for hydropower house. The influencing factors include calculation model range, boundary condition and water in spiral case. Two practical cases are given. The study indicates that if the whole structure of one unit is taken as calculation model and the boundary condition is simulated properly, the calculation result is deemed to be precise enough to reflect practical situation. The mass of water does not affect the radical free vibration characteristics of concrete structure of powerhouses.