Development of a distributed three-dimensional inclinometer based on OFDR technology and the Frenet-Serret equations
来源：Measurement
作者：Pei H.; Zhang F.; Zhu H.; Liu J.; Ning F.; Chen W.
作者单位：大连理工大学, 南京大学
出版时间：2023-12-01
DOI：10.1016/j.measurement.2023.113769
【研究背景】
近年来，由于城市化和人口增长等原因，土壤侵蚀和山体滑坡等地质灾害频繁发生，给人们的生命财产安全带来了威胁。因此，对于山体滑坡的监测和预测变得尤为重要。目前，倾斜仪是监测山体滑坡内部位移的重要工具。但是，现有的光纤倾斜仪无法监测三维变形。因此，如何开发一种能够实现三维变形监测的倾斜仪成为了当前研究领域的一个难点。
【研究内容】
为了解决现有光纤倾斜仪无法监测三维变形的问题，本研究提出了一种基于光频域反射技术（OFDR）的分布式倾斜仪。该倾斜仪利用Frenet-Serret方程实现三维位移计算。为了验证该方法的可行性，本研究进行了有限元分析和实验测试，并将结果与共轭梁法和有限差分算法进行了比较。结果表明，该方法的位移计算可靠性高，分布式倾斜仪可以在空间中实现三维变形测量。测量结果令人满意，OFDR倾斜仪每单位长度的最大误差在0.45%以内，从而可以有效地测量山体滑坡内部位移。
【研究意义】
本研究提出了一种基于OFDR技术和Frenet-Serret方程的分布式三维倾斜仪，可以有效地监测山体滑坡内部位移，填补了现有光纤倾斜仪无法监测三维变形的空白。该研究的创新点在于利用OFDR技术实现了三维变形监测，为山体滑坡的监测和预测提供了新的手段和技术支持。本研究的成果对于提高山体滑坡的预测和监测能力，保护人民生命财产安全，具有重要的现实意义。
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