载重车辆-伸缩缝耦合系统的垂向振动数值模拟方法

Numerical Simulation Method for Vertical Vibration of Heavy Vehicle-Expansion Joint Coupled System

为研究车辆对大位移伸缩缝振动特性的影响,考虑轮胎载重车辆过大位移桥梁伸缩缝时的真实激励特性,提出了一种载重车辆-伸缩缝耦合系统垂向动力学模型,同时引入新型快速积分法对数值模型进行求解.以ZL1600模数式大位移伸缩缝为研究对象,通过仿真结果与试验测试结果的对比验证模型有效性,并基于此模型分析了轮胎载重车辆对大位移伸缩缝的冲击效应.研究结果表明:中梁测点垂向速度的动力学模型仿真结果能较好地匹配试验测试结果,仿真得到中梁测点最大下沉位移的偏差均小于10.0%,表明该模型具有较高的计算精度;车辆轮胎力的最大冲击系数出现在车轮驶上伸缩缝后方桥面时,需要考虑对此处结构进行加强;车辆轮胎对伸缩缝中梁和后方桥面的冲击系数均随车速的增大而增大,最大冲击系数分别为0.67和0.82,均超过了国内现行规范的推荐值0.45,应得到重视.

To study the influence of vehicles on vibration characteristics of large displacement expansion joints,a vertical dynamic model of heavy vehicle-expansion joint coupled system is established,considering the real load characteristics of a wheeled heavy vehicle when passing a large displacement bridge expansion joint.The new fast integration method is introduced to solve the numerical model.Taking ZL1600 modular large displacement expansion joint as the research object,the validity of the model is verified by comparing simulation results with test results.Based on the model,the impact effect of wheeled heavy vehicle on expansion joint is analyzed.The results show that the dynamic model simulation results of vertical velocity at the center beam test points can be well matched with the test results.The deviations of center beam maximum sinking displacements between simulation results and test results are less than 10.0%,which indicates that the model has high calculation accuracy.The maximum impact factor of tire loads occurs when the wheel drives on the bridge deck behind the expansion joint.Therefore,it is necessary to strengthen the nearby structure.The impact factor of tire loads on the center beams and the rear bridge deck increases with speed.The maximum impact factors are 0.67 and 0.82 respectively,both exceeding the recommended value of 0.45 in the current Chinese standard.It should be given more attention.