基于布里渊散射光时域反射测量技术的分布式光纤测斜管研发与应用

摘要

To ensure the safety and stability of large foundation pit during the excavation and sustainment, the inclinometer tube is applied to monitoring deep soil movement.The principle and characteristic of Brillouin optical time-domain reflectometer(BOTDR)are introduced,a new distributed measurement optical fiber inclinometer tube based on BOTDR is developed to improve the accuracy of monitoring results and automation level of the monitoring process.The development process and method of optical inclinometer tube are introduced detailedly.The strain of inclinometer tube and the displacement of deep soil are obtained by applying distributed measurement optical fiber inclinometer tube to foundation pit monitoring.The measured results show that the distributed measurement optical fiber inclinometer tube based on BOTDR can reflect the deformation of foundation pit accurately.It has higher measuring precision,more measuring data and easier monitoring process than traditional monitoring methods.%深层水平位移是基坑工程安全监控的重要监测指标,通常采用测斜管进行监测,确保基坑的安全与稳定.为了提高测斜管监测结果的精度与自动化程度,弥补传统监测手段的局限与不足,从基于布里渊光时域反射计(BOTDR)光纤监测技术原理和特点出发,研发了一种基于BOTDR技术的分布式光纤测斜管,详细介绍了其制作方法与施工工艺,通过现场基坑测试,获得了分布式光纤测斜管的应变信息,并通过数据分析获得了基坑深层水平位移变化.结果表明:基于BOTDR技术的分布式光纤测斜管能够准确地反映基坑的变形情况,具有很好的工程适用性,且与传统监测手段相比,具有测量精度高、数据采集全面、监测方便、能够实时监测等优点,在基坑工程的变形监测中具有显著的优越性和推广价值.