形函数时变性对汽车公路梁桥竖向耦合振动影响分析

摘要

采用梁单元离散公路梁桥，每辆汽车由多刚体模型模拟，将汽车与桥梁视为相互作用的整体系统，建立汽车-梁桥耦合时变系统的竖向振动方程。引入三次Hermite 插值形函数，考虑车桥相互作用引起的梁单元形函数时变性，推导出形函数时变性在车桥耦合振动方程中的贡献值，并编制计算程序。通过具体算例分析梁单元形函数时变性对汽车-梁桥竖向振动响应影响。计算结果表明，在高速行车的车桥振动分析中，梁单元形函数时变性对公路梁桥竖向耦合振动影响显著，模拟计算时应予以考虑。%The highway beam bridge was modeled by beam elements,the car was simulated by multi-body model, vehicles and the bridge were taken as an interactive system,and then the vertical vibration equation of the vehicle-beam bridge coupling time-varying system was established.A three order Hermite interpolation function was introduced,and the time variability of the beam element interpolation function (TVEIF ),caused by the vehicle-bridge interaction,was considered.The contribution of TVEIF to the equation of the bridge-vehicle system was deduced and a program was compiled.The effect of TVEIF on the vertical vibration response of the vehicle-beam bridge system was analyzed through a specific example.The results show that the effect of TVEIF on the vehicle-bridge coupling vertical vibration of highway beam bridge is significant when the vehicles are crossing the bridge with high speed,so it should be considered in vibration simulation calculation for vehicle-beam bridge coupling systems.