基于光纤传感的石膏矿地面塌陷监测预警系统

Monitoring and warning system for ground subsidence of gypsum mine based on fiber sensing

近年来,江苏省邳州市北部石膏矿区发生了20多起采空塌陷灾害。由于传统的采空区地表土体变形监测方法均难以满足采空区地面塌陷监测超前预报的要求,为解决石膏矿区采空塌陷监测预警机制缺乏的问题,邳北石膏矿区开展了基于光纤传感技术的监测预警工作。根据前期调查分析和数值模拟等成果推导石膏矿地面塌陷机理,并采用光纤传感器对采空区上覆松散层底部含水层地下水位动态监测、深部岩土体位移监测及微震监测。在监测过程中,当水位变动幅度、岩土体位移突然超出正常波动值时或接收到较强震动信号时触发报警,在地面塌陷发生前期进行有效的预警,为防灾减灾工作提供充足的准备时间。通过监测预警工作的实施,验证了这些监测预警手段的有效性,可以为矿区地面塌陷地质灾害的监测、预报以及防治提供数据基础与科学依据,也可为石膏矿和其它类似条件的地面塌陷地质灾害防治和监测预警工作提供参考。

In recent years,the mined-out area resulting in more than 20 goaf collapse disasters in the north Pizhou,Jiangsu Province.The traditional monitoring method of surface soil deformation is difficult to meet the requirement of advance prediction of surface subsidence.In order to solve the lack of monitoring and early warning mechanism of mined-out subsidence in gypsum mining area,a monitoring and early warning system based on fiber sensing technology was developed in this area.According to the results of preliminary investigation,analysis and numerical simulation,the ground collapse mechanism of gypsum mine is deduced,dynamic monitoring of groundwater level,displacement of deep rock and soil mass and microseismic monitoring of bottom aquifer above loose layer were monitored by optical fiber sensor,in the course of monitoring,the alarm will be triggered when the fluctuation of water level and the displacement of rock and soil suddenly exceed the normal fluctuation value or when a strong vibration signal is received,and the effective early warning will be carried out in the early stage of the ground collapse,and can provide adequate lead time for disaster prevention and mitigation efforts.Through the implementation of monitoring and early-warning work,the validity of these monitoring and early-warning means has been verified,which can provide data basis and scientific basis for the monitoring,prediction and prevention of ground subsidence in mining areas,it can also provide reference for prevention,control,monitoring and early warning of ground collapse geological disaster in gypsum mine and other similar conditions.