连续梁桥车辆动态称重系数解析与试验验证

Analysis and Experimental Verification of Vehicle Weighting Coefficients for Continuous Beam

基于桥梁响应的车辆动态称重方法具有成本低、易维护和耐久性好等优点,但其称重精度依赖于称重系数的准确性。以典型三等跨预应力混凝土连续小箱梁桥为应用背景,首先推导了车辆重量与桥梁响应指标之间的相关数学表达式,给出了车辆称重系数的定义和理论解析解,同时指出针对实际宽幅桥梁,根据车辆横向位置修正对应的称重系数;其次,利用两车道随机车流对该桥有限元模型进行加载并提取桥梁响应,得到车重与响应之间的相关曲线和相关系数;最后,在实桥上设计安装了桥梁动态称重系统和路面动态称重系统用于监测通行车辆信息,通过匹配算法得到大数据统计下的车辆称重系数。研究结果表明,所提出的车辆称重系数解析解与仿真结果误差为1.8%,实测称重系数与理论解析解、数值仿真结果绝对误差为1.73%。研究结果对诸如简支梁、不等跨连续梁等其他类型桥梁提供了研究思路,以得到桥梁不同位置处的车辆称重系数,同时建议在实际工程应用中分别对理论、仿真和实测的称重系数相互校核,提高标定的准确性。

The vehicle weighing method using bridge response has the advantages of low cost,easy maintenance and good durability.Its weighting accuracy depends on the accuracy of the weighting coefficients.Taking a typical three-span prestressed concrete continuous small box girder bridge as the application background,the mathematical expressions correlating vehicle weight and bridge response indices were derived.The definition and theoretical analysis of vehicle weighing coefficients were given,and the correction factor for the lateral position of the weighing coefficients was proposed for actual wide bridges.Secondly,the finite element model of the bridge was established and loaded with random traffic flow of two lanes to extract bridge response.Finally,a bridge weigh-in-motion system and a pavement weigh-in-motion system were designed and installed on the actual bridge to monitor the information of passing vehicles,and the vehicle weighing coefficients under big data statistics were obtained through matching algorithms.Research results show that the theoretical weighting coefficients are consistent with the numerical simulation results,with an error of 1.8%.The measured calibration coefficients are also consistent with the theoretical and numerical simulation results,with an absolute error of 1.73%.The research results provide research ideas for other types of bridges such as simply supported beams and unequal span continuous beams,in order to obtain vehicle weighing coefficients at different positions of the bridge.It is also recommended to cross check the theoretical,simulated and measured weighing coefficients in practical engineering applications to improve the accuracy of calibration.