煤岩体应力动态监测系统开发及应用

Development and application of dynamic stress monitoring system for coal and rock mass

煤岩体应力是矿井支护设计、矿压分析、冲击地压等煤岩动力灾害预测与防治的重要依据。为了定向测试煤岩体多向应力及其演化规律,自主研发了三向缸体压力感应器和煤岩体应力动态监测系统。感应器上设置的感应片可实现与煤岩体主动有效耦合,通过感应片伸缩变形和油压变化来反映煤岩体应力大小,进而通过该监测系统实现煤岩体应力多向、实时连续测量。将该系统应用于煤矿现场采动应力监测,分析了采场应力分布及演化规律。监测结果表明,多测点应力测量可反映巷道围岩应力分布及随采动等演化规律,可以确定巷道围岩卸压带范围、应力集中范围及应力集中程度等。实测分析得到了工作面巷道内帮煤体的三向正应力分布规律;各测点应力变化趋势基本一致,同一测点3个方向正应力并非完全同步;测试工作面巷旁存在2个应力峰值区及2个卸压带。该系统为定向监测煤岩体应力提供了有效手段和方法,可用于矿山应力监测分析、围岩稳定性监测分析、冲击地压等煤岩动力灾害监测预警等。

Stress of coal and rock provides important basis for supporting design of mine,strata stress analysis,rock burst and other dynamic disasters prediction and prevention.In order to measure the stresses of coal and rock in various directions and obtain their evolution laws,stress sensors within three directions and dynamic stress monitoring system of coal and rock are developed.The chip set on the stress sensor can effectively couple with coal and rock,and the stress can be measured by the flexible deformation of sensor chip and oil pressure.By this monitoring system,the stresses of coal and rock in various directions can be monitored continuously in real time.And this system was applied to mine stress monitoring and its evolution laws analysis.The results showed that the stress distribution of surrounding roadway and it′s evolution laws,the stress relief region,the stress concentration range and degree could be gained through multi-points arrangement.According to the measured results,the normal stress distribution laws inside coal mass of the roadway were gained in three perpendicular directions,which displayed that the stress variation trend of every point coincided,but the normal stress of various directions about the same point was not synchronous.It revealed there were two stress relief and concentration regions beside the roadway.This system provides effective means and methods for directional monitoring coal and rock stress,which can be used to the analysis of mine stress,the monitoring of surrounding rock stability and early warning of rock burst and other dynamic disasters.