Research on finite element analysis and modelling of bolted joint

Abstract

The bolted joint is one of the most widely used fixed joints in mechanical structures, and has considerable impact on the dynamic characteristics of mechanical structures. Therefore, the correctness of bolt joint modeling is the key to the dynamic performance analysis and behavior prediction of the entire mechanical system. In this paper, the stiffness of the lapped beam structures was calculated according to the empirical formula for the dynamic stiffness of the joint surface, and an equivalent model of the bolt joint was established using the spring-damping element in ANSYS. Meanwhile, another equivalent model of the bolt joint was established by using the virtual material layer method. Finally, the modal test of the lapped beam structure with the bolted joint was carried out, and the simulation results obtained from the two theoretical modeling methods were compared with the modal test results. The results showed that the modeling method using the spring-damping element has higher modeling accuracy compared with the virtual material layer method, and the errors in the first six natural frequencies were within 2.2%, which verified the correctness and effectiveness of the spring-damping element modeling method, and provided a basis for the modeling of bolted joints in practical structures.