基于动应变的桥梁动态称重及其优化算法

Bridge weigh-in-motion and its optimization algorithm based on dynamic strain

将桥梁视为"秤"对车辆进行动态称重,是一种获取桥面移动车辆行驶速度、轴距、轴重等信息的新方法。本文以桥梁不同截面动应变响应为对象,采用"峰值法"识别车辆速度、轴距,引入最小二乘原理识别车辆各轴重,再结合梯度法对初始识别结果值进行局部优化,最后建立车-桥耦合振动模型模拟桥梁动应变,对桥梁动态称重及优化算法进行数值仿真。结果表明,对已经具备一定精度的动态称重初始结果值进行局部优化能进一步提高精度,满足工程应用要求。

Using a bridge as a scale to weigh trucks in motion is a novel method of getting their velocities, wheel bases, axle loads and other truck information. Here, based on dynamic strains of different cross-sections of a bridge, the peak algorithm and the least square method were employed to indentify running speed, wheelbase and axle load of a vehicle in motion, respectively. In addition, the gradient method was used to optimize the initial recognition results. The bridge-vehicle coupled vibration was modeled to simulate the dynamic strain responses of the bridge and numerical analysis were also performed to deal with the results. The results showed that the local optimization on the initial recognition results already having a certain precision can further improve the accuracy to meet the engineering requirement.