Tangential Dynamic Behavior Identification of Bolt Joints

Identification of joints dynamic behaviors has become a universal issue, which is critical for accurate modeling of mechanical system. In this paper, a thorough methodology is presented to investigate bolt joint tangential dynamic characteristics. Substructure synthesis, based on structure frequency respond functions(FRFs), is employed as the theory mainline to construct the fundamental equation for identifying bolt joint tangential dynamic behaviors. Tangential dynamic stiffness of bolt joint, Za, is deduced afterwards. By virtue of singular value decomposition and least squares approaches, equivalent tangential stiffness parameters, ka, and damping parameter, ca, utilized for bolt joint tangential dynamic modeling in the following step, are identified. Validity of the proposed tangential dynamic model is demonstrated by comparing FRFs obtained numerically and experimentally. Comparison results indicate that frequencies errors of first three characteristic peaks are 1.38%, 1.51% and 0.84%, respectively. It is sufficient to prove that the proposed methodology is efficient for identifying bolt joint tangential dynamic behaviors and the resulting equivalent dynamic parameters are highly accurate so that they can be regarded as theory and data supports for accurate modeling of mechanical system. © 2019, Editorial Department of JVMD. All right reserved.