风与车流联合作用下在役桥行车舒适性研究

现有基于风-汽车-桥梁耦合振动的行车舒适性研究中,较少考虑了车流随机性和路面等级退化因素,致使分析成果具有一定局限性.本文综合考虑了车流随机性和路面等级退化等因素,运用一种新的车辆和路面等级退化模型分析大跨度桥梁的振动及行车舒适性.建立一个包含座椅及车辆纵向振动的24自由度空间车辆模型;基于考虑邻近车辆影响的改进CA(Cellular Automation-元胞自动基)模型和路面退化模型,通过桥梁和车辆相互作用力关系,建立了风-车流-桥梁系统的耦合振动方程.数值计算表明:本文所提出的方法能够合理地模拟风-车流-桥梁系统的耦合振动,且驾驶员座椅模型的各向振动对行车舒适性有显著影响.

Ride Comfort of Existing Bridges under Combined Loads of Traffic and Wind

The existing studies of ride comfort are based on wind-vehicle-bridge coupled vibration, which seldom consider the effects of both traffic random characters and road surface progressive deterioration, thus they cannot match very well for the real situation of the bridge under the random traffic loads. Based on wind-traffic-bridge system under random traffic loads, this paper studied the ride comforts taking into account the road surface progressive deterioration. We presented a three-dimensional vehicle model with 24 degrees-of-freedoms (DOFs) including a three-dimensional suspension seat model and longitudinal vibration of the vehicle, and then introduced an improved CA model considering the influence of the next-nearest neighbor vehicle and a progressive deterioration model for road-roughness. The wind-traffic-bridge coupled equations were established by combining the motion equations of both the bridge and vehicles using the displacement relationship and interaction force relationship at the patch contact. The numerical simulations show that the proposed method can rationally simulate the vibration of the wind-traffic-bridge coupled system; and the 3-D vibrations of the driver seat model can significantly affect the drive comforts.