Coupled vibration analysis of suspended monorail train and curved bridge considering nonlinear wheel-track contact relation

This work elaborately conducts the coupled vibration analysis of suspended monorail train and curved bridge (SMTCB) considering a nonlinear wheel-track contact relation. First, a high-efficiency coupled dynamic model of the SMTCB is developed based on a co-simulation method where the train subsystem is established using the multi-body dynamics software UM and the curved bridge subsystem is built adopting the finite element software ANSYS, whose modal information is extracted to put into the UM software; Two subsystems of the train and bridge are coupled by an improved wheel-track contact model (IWTCM) that considers the real nonlinear radial stiffness of a suspended monorail rubber tire. Then, the effects of the extracted modal orders of the bridge on vehicle-bridge vibrational responses are analyzed and discussed in detail, and the minimum modal orders extracted of the bridge that guarantee the convergence and accuracy of the proposed model are also obtained. Subsequently, the vibrational responses obtained by numerical simulation and field test are compared when the vehicle runs on a curved bridge, validating the reliability of the developed model. On this basis, by comparing the vehicle-bridge vibration responses between the traditional FIALA tire model and the IWTCM, some remarkable differences are distinguished, revealing the significances and advantages of adopting the IWTCM. Finally, employing the developed model, the vehicle-curved bridge coupled vibration features are investigated comprehensively and several key parameters are also chosen reasonably. The research results may provide some useful guidance for the design of the SMTCB.