分布式布里渊光纤传感技术在海堤沉降监测中的应用

Application of BOTDR to monitoring sea dyke subsidence

阐述了海堤沉降长期在线监测的重要性,介绍了利用分布式布里渊光纤传感技术(布里渊光纤应变仪BOTDR)对上海临港新城海堤k3+640和k3+780两个断面进行长期监测的系统设计、实施和监测结果。通过对k3+780断面光纤传感数据和水准观测数据比对表明,最大应变位置与现场冲泥管带位置吻合;计算得到了断面沉降分布,其趋势和现场情况以及水准测量结果吻合;5个原位观测点上最大偏差为94 mm,平均偏差为39.2 mm。

The importance of long-term on-line monitoring sea dyke subsidence is described. An experimental system, which monitors Shanghai Lingang sea dyke section k3＋640 and k3＋780 using distributed Brillouin optical fiber sensing technology （BOTDR）, is introduced. The monitoring data from optical fiber sensor system and traditional leveling observation are compared; and the position of the largest strain coincides with the position of the load. The subsidence distribution is calculated; and it coincides with on-site load status and the result of leveling observation. The maximum deviation of five in-situ observation points is 94 mm; the average diviation is 39.2 mm.