深部围岩位移破坏及穿层钻孔封孔优化

Displacement failure of deep surrounding rock and optimization of sealing process of through holes

基于深部和浅部巷道围岩地应力差异,理论分析了浅部巷道围岩特征为单应力峰值、单一破裂区,深部巷道围岩特征为多应力峰值、分区破裂。现场观测了深部巷道围岩位移呈现波峰、波谷交替出现的规律,波峰部位为破坏区,波谷部位为非破坏区;破坏呈现破裂区和完整区间隔的分区破裂现象,破裂区一般为4~5个,破裂区范围明显大于浅部巷道围岩破裂部位。优化了穿层钻孔封孔深度为8~10 m,通过单孔抽采量考察,结果表明穿层钻孔单孔抽采纯量高达28 m^3/d,平均抽采浓度达20%以上,抽采量提高近10倍,抽采浓度提高4倍以上,抽采效果显著提高。

Based on the difference of ground stress between deep surrounding rock and shal- low surrounding rock, the features of surrounding rock of roadway were theoretically analyzed, which were single peak stress and single disintegration of shallow surrounding rock and multi peak stress and zonal disintegration of deep surrounding rock. Field observation shows the dis- placement of deep surrounding rock of roadway takes on alternative appearance of the peak and trough of stress, the position corresponding to the peak of stress is disintegration zone and the positon corresponding to the trough of stress is not disintegration zone; the disintegration takes on zonal disintegration which disintegration zone and integration zone intervally appear, the disin- tegration zone is generally 4 to 5 and the disintegration range o{ deep surrounding rock is obvious- ly greater than the disintegration range of shallow surrounding rock. The optimal sealing depth of through hole is 8 to 10 meters, the investigation results of quantity of drainage of single through hole show that net quantity of drainage of through hole reaches up to 28 m3/d, increasing by a- bout 10 times, the methane gas concentration of drainage reaches more than 20%, increasing by more than 4 times, the effect of drainage is obviously improved.