三维激光扫描技术在路堤沉降观测中的应用

Application of 3D laser scanning technology in the observation of embankment settlements

为有效解决现阶段路基整体差异沉降无法有效监测,仅通过单点监测反应沉降的问题,结合三维激光扫描技术在农林、矿井及隧道等领域的成功应用,将其引入拓宽路基的沉降整体监测。对石安高速公路改扩建工程的新旧路基整体沉降进行动态监测,分析新旧路堤差异沉降的整体变化规律,并与单点沉降进行对比,验证三维激光扫描技术在公路改扩建工程中的适应性。结果表明:新老路堤交接处和路基无处置措施处的沉降量变化最明显;经过4个月的固结,传统的单点观测沉降量最大为1.6 mm;三维激光扫描测得整体沉降量小于1 mm,观测结果准确性提高约38%,且更能反应整体沉降的动态,监测结果误差满足精度要求,同时兼具快速、准确和整体观测的优点,说明三维激光扫描技术可用于拓宽工程的新旧路堤沉降监测和评价。

At present,the overall differential settlements of embankments cannot be monitored effectively and the settlement can be evaluated only by single-point monitoring.Therefore,in this paper,the 3D laser scanning technology was introduced to help solve these problems thanks to its rapid scanning and analyzing of the overall settlement of an embankment.The overall settlement of the new and old embankments of Xi’an highway were dynamically monitored with the law of differential settlement examined of the new and old embankments.A comparison with the single-point settlement was then carried out in order to verify the adaptability of 3D laser scanner in highway extension construction.The results show that the settlement at the junctions of new and old embankments and subgrade without disposal were the most obvious.Furthermore,after 4 months consolidation,the maximum settlement measured by the traditional single-point monitoring method was 1.6 mm while the overall settlement values by 3D laser scanning was less than 1 mm,indicating that the observation accuracy was improved by about 38%,and that it could reflect the overall settlement dynamics much better.In addition,the error of the 3D laser scanning monitoring results met the precision requirement,with its advantages of fast and accurate observation,which clearly show that the 3D laser scanning technology could be used to monitor and evaluate the settlements of new and old embankments in extension projects.