高水压大直径越江电力管廊隧道结构健康监测方案探讨

高水压长期侵蚀、穿越软弱下卧土层复杂多变等特点使得水下电力管廊隧道结构的运营安全问题较为突出,合理开展健康监测是极为必要的。本文依托苏通GIL综合管廊大直径越江盾构隧道工程,在调研隧址地质条件、设计方案及运营控制要求的基础上,结合水土压力计算与结构力学性能分析,开展大直径高水压越江盾构隧道结构健康监测方案的研究,确定了隧道结构的监测项目、监测部位、监测仪器选型方案及数据采集、传输与处理等技术,并对监测数据的数字化管理方案进行探讨。通过研究,明确以深槽最高水压、河床冲淤剧烈、覆土变化明显、超浅埋区段及淤泥质软黏土、粉土等典型土层为重点监测部位,布设13个断面开展水土压力、钢筋应力、螺栓轴力、接缝张开监测,并全线实施沉降监测;设计了集工程信息可视化、健康监测实时管理、结构安全动态评估、仪器故障诊断等功能于一体的健康监测数字化管理方案,指导了依托工程健康监测的实施及数据评价管理。方案可供类似水下隧道健康监测参考。

Structural Health Monitoring Program and Application for High Water Pressure and Large Diameter Cross-river Power Pipe Tunnel

The characteristics of long-term erosion of high water pressure and crossing complicated and changeable soft substratum make the operation and safety of underwater power utility tunnel structure more prominent.Therefore,it is extremely necessary to carry out reasonable health monitoring. In this paper, supported by Sutong GIL largediameterutility shield tunnel, the health monitoring project of large diameter and high water pressure crossing river shieldtunnel was carried out through investigating tunnel site geological conditions, design and operation control requirementsand combining water and soil pressure calculation and structural mechanics performance analysis, the monitoring items,monitoring parts of tunnel structure, selection of monitoring instrument and the technology of collection, transfer andprocessing of monitoring data of solution were determined in this paper. The digital management project of monitoringdata was also discussed. Through research, 1) it was clear that the key monitoring parts were the highest water pressurein deep groove, severe scouring and silting in riverbed, obvious thickness changes of overburden soil, ultra-shallowburied section, silty soft clay, silty soil and other typical soil layers.13 monitoring sections were arranged to monitor soiland water pressure, rebar stress, bolt axial force and joint opening and settlement monitoring was arranged along thewhole line. A digital health monitoring program which integrated information visualization, real-time health monitoringmanagement, structural safety dynamic evaluation, fault diagnosis of instrument and other functions was designed to guidethe implementation of health monitoring and data evaluation management relying on engineering. The scheme can be usedas reference for health monitoring of similar underwater tunnels.