Finite element modelling and modal analysis of structure with bolted joints

Finite element modelling and modal analysis of structure with bolted joints

Liping He1, Limiao Qian1, Zijing Wang1, Kai Long2

1Beijing Institute of Radio Measurement, Beijing, China

2State Key Laboratory for Alternate Electrical Power System with Renewable Energy Sources, North China Electric Power University, Beijing, China

In order to investigate a modal analysis of structure with bolted joints, five kinds of finite element models, a solid bolt model, a no-bolt model, a modified bolt model, a beam bolt model and a rigid bolt model, are introduced. Among these models, the solid bolt model, modified bolt model and rigid bolt model provide good accurate responses compared with the modal test results. The solid bolt model, which can also be used for stress analysis, is recommended in view of applicability. The rigid bolt model is recommended in view of usefulness and effectiveness. For bolted flanged connection, the magnitude of bolt pretension has little influence to structural modes. To improve the calculation accuracy of higher modes, a better idea is to modify the finite model by modal test.