Dynamic Response Analysis Of Long Span Continuous Girder Bridge With Moving Vehicles

Abstract:Dynamic effect on long span continuous girder bridge under moving vehicles is remarkable. Therefor on the background of Youshui Bridge, dynamic response of time-variant vehicle-bridge coupled system of long span continuous girder bridge was analyzed in this study, and major work are summarized as follows:Finite element method of dynamic analysis of long span continuous girder bridge was introduced, and the model of dynamic analysis of bridge structure was established, where the characteristic matrix of bridge structure such as unite stiffness matrix, unite mass matrix and unite damping matrix were derived. On the basis of comparsion of different freedom vehicle models, a seven degree-freedomed vehicle model under moving vehicles was established and the total vibration potential energy was devrived. Meanwhile, the analysis methods of the pavement imperfection were expounded, and the pavement imperfection of the investigated bridge was simulated quantitatively.Based on the stationary value principle of the total dynamic potential energy in elastic system and sit-in-right-position rule, the motion equations of time-variant vehicle-bridge coupled system were established. Dynamic responses of Youshui Bridge under moving vehicles were analyzed by using the VBS program, and the vehicle impact coefficient was calculated and compared with the result of specification. Moreover, the bridge vibration comfort was evaluated with Dickman index.Dynamic response parameters of time-variant vehicle-bridge coupled system were analyzed, on the basis of which, the impact of parameters such as the bridge deck imperfection, vehicle speed, vehicle load, vehicle distance and lane number on dynamic response and vibration Dickman comfort of the Youshui Bridge was conducted. Furthermore, the influence of parameters including the bridge deck imperfection, vehicle speed and vehicle load on dynamic response and driving ISO standard, Sperling comfort of the vehicle was also conduted. The conclusions in this study would provide references for construction and design of highway long span continuous girder bridge, both daily operation and management.