Theoretical and experimental studies on vibration characteristics of bolted joint multi-plate structures

Abstract

The bolted joint multi-plate structures are widely used in practical engineering, but their theoretical dynamic model is hard to find in literature. The main purpose of this paper is to establish a general dynamic model of bolted joint multi-plate structures with flanges, and to investigate its vibration characteristics from both theoretical and experimental aspects. Both the flange effect and contact pressure distribution in the bolted joint affected region (BJAR) are considered. Artificial spring sets with variable stiffness are adopted to simulate the non-uniform distributed contact pressure in BJAR. The governing equations are derived based on the Kirchhoff plate theory and Euler-Bernoulli beam theory. The Chebyshev polynomials are used as admissible displacement functions. Then, the free vibration and forced vibration under base excitation are solved by means of the Rayleigh-Ritz method and Newmark-beta method, respectively. The experimental studies, including modal test and vibration response test, are conducted on a bolted joint two-plate specimen to verify the accuracy of the theoretical model. Results show that the present model is capable of realizing reliable vibration prediction and can be conveniently extended to the structure with an arbitrary number of plates and bolts. For the bolted structures, considering the pressure distribution in the connection interfaces can significantly improve the accuracy of theoretical results.