基于交通影像的非接触式桥梁动态称重系统

Non-contact Bridge Weigh-in-Motion System Based on Traffic Surveillance Video

提出一种基于交通影像的非接触式桥梁动态称重方法。以桥上已有交通监控摄像头为非接触式传感器获取桥梁位移动态响应,进而计算过桥车辆荷载。以倾斜摄影获取多种工况下简支梁试验桥动力响应视频;通过平均绝对差算法追踪特征点,获得测点位移影响线;最后基于影响线面积计算过桥车辆荷载。试验结果表明:获得的试验桥位移响应与传统接触式测量结果吻合较好,在实验室条件下,能够识别模型桥上不同速度(0.09~0.3 m/s)与质量(4.15~8.15 kg)的过桥车辆荷载,最大误差为9.5%。所提出的非接触式桥梁动态称重系统为中小桥梁过桥车辆荷载的识别提供一种新的解决思路。

In order to meet the demand of a large number of small and medium-sized bridges for monitoring the load of crossing vehicles,a non-contact bridge Weigh-in-Motion method based on traffic surveillance video is proposed.The existing traffic surveillance cameras on the bridge are used as non-contact sensors to obtain the dynamic response of the bridge displacement,and then calculate the load of crossing vehicles.The dynamic response video of the simply supported girder test bridge is obtained by tilt photography under various working conditions.The mean absolute differences(MAD)algorithm is used to track the feature points,and the tilt photography correction algorithm and camera displacement correction algorithm are constructed to improve the measurement accuracy of the displacement response,and obtain the displacement influence line of the measurement points.Finally,the overpass vehicle load is calculated based on the influence line area.The test results show that the obtained displacement response of the test bridge agrees well with the traditional contact measurement results,and under the laboratory conditions,it is able to identify the vehicle loads on the model bridge with different speeds(0.09-0.3 m/s)and weights(4.15-8.15 kg)with a maximum error of 9.5%,which presents a new solution to the problem of identifying vehicle loads of small and medium-sized bridges.