沿空掘巷窄煤柱变形及控制措施

Deformation and Control Measures of Narrow Coal Pillar in Gob-Side Entry

针对某矿沿空掘巷窄煤柱支护强度低、易失稳的问题,通过分析煤柱裂隙的分布特征,研究了沿空掘巷窄煤柱变形破坏机理及控制技术。结果表明:沿空掘巷煤柱内部可划分为外裂隙区、内裂隙区和完整区,其中完整区偏向采空区侧;窄煤柱外裂隙区主要为拉剪复杂破坏,内裂隙区为张拉破坏,煤柱失稳主要由内裂隙区的张拉裂隙引起的整个外裂隙区的剪切滑移造成;窄煤柱的稳定性可通过减小内裂隙区的长度和增加内裂隙区的承载能力来实现。

Aiming at the problems of poor support strength and instability of narrow coal pillar in gob-side entry in a coal mine,the deformation failure mechanism and control technology of narrow coal pillar in gob-side entry were studied by analyzing the distribution characteristics of cracks in coal pillar.The results are concluded as follows.Firstly,the interior of coal pillar in gobside entry can be divided into outer fracture area,inner fracture area and complete area,in which the complete area is inclined to the side of goaf.Secondly,in the outer fracture area of coal pillar,there are mainly complex tensile shear failure,while the inner fracture area mainly has tensile failure.The instability of coal pillar is mainly due to the shear slip of the whole outer fracture zone caused by the tensile crack in the inner fracture zone.Thirdly,the stability of narrow coal pillar can be achieved by reducing the length of the inner fracture zone and increasing the bearing capacity of the inner fracture zone.