检测车轨迹偏移对沥青路面磨耗计算误差的影响

Influence of detecting track offset on calculation error of asphalt pavement wearing

为研究检测车轨迹偏移对沥青路面磨耗程度计算结果的影响,根据实测三维激光高程点云数据重构了3段磨耗等级分别为轻度、中度和重度的路表模型,绘制其全车道平均断面构造深度(MPD)热力分布图。采用三线法计算路面磨耗率XWR,分别模拟检测车向左、右偏移100和200 mm后的测线轨迹,以偏移前、后磨耗率XWR的绝对误差和相对误差为评价指标,分析轨迹偏移对磨耗率计算误差的影响规律。结果表明:检测车轨迹偏移距离越大,路面磨耗率计算的绝对误差和相对误差越大,轻度、中度和重度3个不同严重程度磨耗路段的磨耗率最大绝对误差分别为5.95%、10.71%和12.39%;路面磨耗程度越严重,磨耗率计算误差越大,较大的误差可能产生路面磨耗等级的低估,进而导致路况评价和养护决策的误判;增加测线数量、减小测线间距是降低偏移误差和提升磨耗检测准确性的有效措施。

To study the influence of the vehicle detecting track offset on the calculation results of the degree of wear of asphalt pavement,three models of pavement with light,medium,and heavy wear grades were reconstructed based on the measured 3D laser elevation point cloud data,the mean profile depth(MPD)distribution of its full section wear index was drawn.The three-line method was used to calculate the road wear rate XWR,and the track of the measuring line after the testing vehicle was offset to the left and right by 100 and 200 mm,respectively,were simulated.The absolute and relative errors of the wear rate XWR before and after the offset were used as evaluation indexes to analyze the influence law of the track offset on the wear rate calculation error.The results show that the larger the offset distance of the detecting track offset,the absolute error and relative error of the wear rate increase gradually.The maximum absolute errors of the wear rate of the light,moderate and heavy wear sections are 5.95%,10.71%,and 12.39%,respectively.The heavy wear level will be misjudged as the medium wear level,which may lead to the underestimation of the grade of pavement wear,and further lead to the misjudgment of road condition evaluation and maintenance decisions.Increasing the number of measured lines and reducing the distance between measured lines are effective measures to reduce the offset error and improve the accuracy of wear detection.