A parametric study on the dynamics of urban transit maglev vehicle running on flexible guideway bridges

The purpose of this study is to develop a numerical model for a dynamic interaction analysis of an actively controlled maglev vehicle and flexible guideway structure. In addition, an investigation is performed of the effect of vehicle and guideway characteristics on dynamic responses of low and medium speed maglev systems. Dynamic governing equations are derived by combining the 5-dof maglev vehicle model, the modal properties of guideway structures and a LQG controller for electromagnetic suspension. An investigation is then carried out on the effect of vehicle models, vehicle speed, irregularity, guideway deflection ratio, span length, span continuity and damping ratio on dynamic responses of the relatively low speed maglev vehicle and guideway structures. From the numerical simulation, it is found that the air gap of the vehicle is strongly affected by vehicle speed, tract roughness and guideway deflection ratio. In particular, the guideway deflection ratio is the most influential parameter which governs the air gap. Continuous span girders are found to be effective in reducing the air gap because of its smooth curvature and small deflection slope near the support. However, the span length and damping ratio of the guideway structure do not affect the air gap. The overall dynamic magnification factor of the guideway girder is not severe compared to the traditional wheel type vehicle.