Application of the Bouc-Wen Model to Bolted Joint Dynamics

Abstract

Various numerical models have been developed to capture the dynamic, hysteretic behavior of different mechanical systems. One such semi-physical model is the Bouc-Wen model, which relates the input displacement to the output restoring force in a hysteretic way. This formulation is intended for any form of hysteresis and was originally applied to force – deflection and flux – current diagrams of mechanical and ferromagnetic hysteresis. Built-up structures are also known to show hysteretic behavior due to the slipping that occurs between interfaces bolted together. This paper tests how effective the Bouc-Wen model is in capturing the power-law damping behavior observed in bolted joints by comparing it with another commonly used numerical model – the Iwan model. While the Iwan element has been proven to be robust and well-suited at capturing the power-law increase in energy dissipation and slow decrease in stiffness with vibration amplitude exhibited by bolted interfaces, numerical integration of the same is currently computationally expensive. Time integration of the Bouc-Wen model, on the other hand, is much more efficient, thus warranting the proposed study.