Zezhou Tian'an Runhong Coal Industry Co., Ltd., Jinneng Holding Group

针对润宏煤业巷道矿压显现强烈、围岩变形突出等问题,系统分析了水力压裂裂缝对围岩变形的影响,选取关键切顶参数,基于数值模拟和现场试验对1311工作面沿空留巷切顶卸压和围岩控制进行了研究。结果表明:沿空巷道矿压显现强烈主要原因为巷道围岩附近存在高应力区;在巷道围岩水力压裂过程中,当围岩主裂缝遇到90°预裂缝时,会发生偏转并以近似双向对称的方式扩展,但当遇到45°预裂缝时,会以单向不对称的方式扩展;通过3DEC对不同切顶参数进行模拟,确定了精确的压裂位置在矿柱与采空区之间,角度为70°,高度为基本顶高度的2/3处,并提出了以“加固锚杆(索)+强力W带”为核心的支护技术,巷道顶底板及两帮变形量较小,实现了试验段巷道的稳定控制。

In response to the problems of strong strata behavior, prominent deformation of surrounding rock and so on in the roadway of Runhong Coal Industry, a systematic analysis is conducted on the influence of hydraulic fracturing cracks on surrounding rock deformation. Key roof cutting parameters are selected, based on numerical simulation and on-site experiments, the roof cutting and pressure relief and surrounding rock control of the 1311 working face retaining roadway along goaf are studied. The results indicate that the strong strata behavior of the roadway along goaf is mainly due to the presence of high stress zones near the roadway surrounding rock; During the hydraulic fracturing process of the roadway surrounding rock, when the main crack of the surrounding rock encounters a 90° precracking, it will deflect and expand in an approximately bidirectional symmetrical manner. However, when encountering a 45° precracking, it will expand in a unidirectional asymmetrical manner; different roof cutting parameters are conducted to be simulated through 3DEC, the precise fracturing position is determined between the mine pillar and the goaf, with an angle of 70° and a height of 2/3 of the basic top height. A support technology centered on "reinforced anchor rods (cables)+powerful W belt" is proposed, the deformation amount of the roadway roof, floor, and two sides are relatively small, achieving stable control of the roadway in the experimental section.