沙曲矿区地应力及采场地压的综合监测与分析

ANALYSIS AND SYNTHETIC MONITORING OF IN-SITU STRESS AND STOPE GROUND PRESSURE IN SHAQU COAL MINE

作为典型复合型顶板的矿山,沙曲矿区的工程地质条件受到多条构造带影响,采煤工作面顶底板均为不稳定性软岩,并含少量裂隙水。为了调查该矿区的地应力条件及地压规律,本文在沙曲矿区的主要开拓巷道中开展了6个地点的地应力测试,结果表明该矿区的地应力场比较均匀,属于准静水应力场。采用现场应力套孔解除和室内围压率测定的方法得到最大水平主应力数值在20.11～22.87(MPa)之间,侧压系数在2.25～2.85范围内,属较高应力;针对24101等工作面的大采高综采巷道进行了煤柱支承压力的现场监测,结果表明24101工作面的巷道煤柱应力分布特点可以分为塑性破坏区、峰值应力区和原岩应力区;同时,对南翼14204工作面顶板进行了离层监测和锚杆测力计载荷观测,结果进一步揭示了随着时间的推移,巷道顶板稳定性的衰减主要是由于离层数量的增加所造成的规律。该地应力及采场地压的综合监测及分析结果对沙曲矿区的支护设计和安全生产具有重要指导和实用价值。

The Shaqu Coal Mine is a typical compound roof mine.Its engineering geological conditions are affected by the multi-strip structural zones.The roof and floor of the working face are composed of instability soft rocks.There is little water in the fractures.This paper investigates the characteristics of the in-situ stress and ground overburden pressure.The In-situ stress testing of six sites were carried out in some main roadways.The test results indicate that in-situ stress field is relatively uniform and belongs to the quasi-hydrostatic stress.The stress trepanning rescission and the surrounding pressure ratio measuring are applied.The tests find that the maximum principal stress value is between 20.11 and 2.87 MPa.The coefficient of the horizontal pressure value is between n 2.25 and 2.85.The results show the site is of high stress.Local monitoring works of coal pillar bearing pressure are performed for the large and high fully-mechanized mining roadway of the No.24101 working face.Distribution of coal pillar bearing pressure of stope can be divided into a plastic failure region,a peak stress region and an in situ stress region.At the same time,the roof separation and bolt dynamometer load are monitored for the No.14201 work face of the south side mine.The monitoring reveals that the main reason of weakened roadway stabilization is the accretion of roof separation with time increasing.These synthetic monitoring results can provide more practical value and basic data for design of the supporting and safety during the mine production.