考虑横竖向车桥耦合曲线桥的动力响应影响

Dynamic Response Considering Vertical and Transverse Vehicle-bridge Coupled Curved Bridge

为探究在有无横竖向车桥耦合作用下曲线桥的动力响应,通过运用有限元软件ANSYS建立三跨混凝土连续曲线桥模型和车辆模型,利用两者之间力的平衡条件和几何协调条件来模拟横竖向车桥耦合作用,并考虑车辆模型的横向振动,建立车-桥相互作用的动力学模型的方法研究了曲线桥的动力响应。结果表明:曲线桥前两阶振型主要以竖向振动为主,而高阶振型,弯扭耦合振动效应明显;70 t车重作用下,1#跨中截面横向力最大值比不考虑横竖向车桥耦合作用增大了1.43%;1#跨中截面横向位移最大值比不考虑横竖向车桥耦合作用增大了10.25%。可见在对曲线桥进行动力响应分析时有必要计入车桥耦合作用;可以通过限载限重防治曲线桥的横向位移的产生。

In order to explore the dynamic response of curved bridge under the coupling action of vertical and transverse vehicle-bridge, a three-span concrete continuous curve bridge model and a vehicle model were established by the finite element software ANSYS. The coupling action of vertical and transverse vehicle-bridge is simulated by the equilibrium and geometric coordination conditions of forces between the two models, and the lateral vibration of the vehicle model was considered. The dynamic response of curved bridge was studied by establishing the dynamic model of vehicle-bridge interaction. The results show that the first two modes of curved bridge are mainly vertical vibration, while the higher modes have obvious effect of bending-torsion coupling vibration. The maximum transverse force of 1# mid-span section increases by 1.43% compared with that without considering the cross-vertical coupling effect, and the maximum transverse displacement of 1# mid-span section increases by 10.25% compared with that without considering the cross-vertical coupling effect. Therefore, it is necessary to take into account the vehicle-bridge coupling in the dynamic response analysis of curved bridges, and the lateral displacement of curved bridges can be prevented by limiting load and weight.