黄土高原半干旱区淤地坝安全监测方法

Safety Monitoring Method of Check Dams in Semi-arid Area of the Loess Plateau

[目的]监测黄土高原半干旱区淤地坝在汛期后形变程度,及时准确发现淤地坝的异常情况,为黄土高原半干旱区淤地坝安全监测提供更加科学可靠的技术方法。[方法]通过三维激光扫描仪对两座淤地坝进行扫描,由此得到高密度、高精度、连续完整的3D点云数据,然后将点云数据导入HD Scene软件进行点云预处理,最后通过Cloud Compare以及Geomagic Control软件进行建模对比分析。[结果]两期点云模型对比可以看出,东沟淤地坝模型大量点云的偏移量在0.05 cm以下,少量点云达到了最大偏移值0.2 cm。西沟淤地坝模型大量点云的偏移量在0.1 cm以下,极少量点云达到了最大偏移值0.4 cm。汛期降水量占全年的77.34%,汛期后两座淤地坝均会产生较小的坝体沉降和水平位移,但西沟淤地坝的形变受水压分量影响更为明显。[结论]将三维激光扫描技术应用于黄土高原半干旱区淤地坝安全监测,可以快速精准掌握淤地坝汛期后是否发生形变以及形变程度,使得淤地坝安全监测工作更加精准可靠。

[Objective]The aims of this study are to monitor the deformation degree of check dam after flood season in semi-arid area of the Loess Plateau and find the abnormal condition of check dam timely and accurately,and to provide a more scientific and reliable technical method for the safety monitoring of check dams in the semi-arid region of the Loess Plateau.[Methods]The two check dams were scanned by a 3D laser scanner,and high-density,high-precision,continuous and complete 3D point cloud data were obtained.Then,the point cloud data were imported into HD Scene software for point cloud pre-processing,and finally,modeling and comparative analysis were performed by Cloud Compare and Geomagic Control software.[Results]The comparison of point cloud models between the two periods showed that the offset of a large number of point clouds in the Donggou check dam model was less than 0.05 cm,and a small number of point clouds reached the maximum offset of 0.2 cm.The offset of a large number of point clouds in the Xigou check dam model was less than 0.1 cm,and a very small number of point clouds reached the maximum offset of 0.4 cm.The precipitation in flood season accounted for 77.34%of the whole year.After flood season,both of the two check dams had small settlement and horizontal displacement,but the deformation of Xigou check dam was more obviously affected by water pressure component.[Conclusion]The application of 3D laser scanning technology to the safety monitoring of check dams in semi-arid areas of the Loess Plateau can quickly and accurately know whether the deformation occurs after flood season and the degree of deformation,which makes the safety monitoring of check dams more accurate and reliable.