Dynamic modelling and vibration analysis of a bolted spigot joint structure considering mating interface friction: simulation and experiment

Bolted spigot joints are widely used connection types in rotating machines, such as the rotor system of aero-engines and combustion gas turbines. Due to the nonlinearity of stiffness and damping caused by the bolted joint and mating interface friction, the dynamic performance of such a connection is too complicated to model. Therefore, the modelling and analysis of bolted spigot joints considering mating interface friction have become of interest in relevant investigations at present, which are of significance for predictions focusing on vibration performance. In this paper, the stick–slip behaviour and hysteresis characteristics of bolted spigot joints caused by mating interface friction are clarified by performing a study with a finite contact element model. Then, a new Iwan-based numerical model of bolted joints is proposed and an effective discretized parameter identification method is developed using the force–displacement results corresponding to the loading process obtained from finite element (FE) simulation results. A comparison study of the established numerical model and the FE simulation results demonstrates the potential of this numerical model to capture the static hysteresis behaviour and vibration performance. Then, the influences of the preload and loading amplitude of bolted joints on the static hysteresis behaviour and vibration performance of the system are examined using the numerical model. Finally, utilizing the results of bolted joint vibration response experiments performed with the established vibration test platform, the results of the numerical simulation are verified. The present study provides a theoretical basis for the design of the joint structure and assembly technology, which further enhances its prediction accuracy of dynamic performance.