受采空区和煤柱影响巷道支护技术应用研究

Application Research on Support Technology of Roadway Affected by Goaf and Coal Pillar

针对受采空区和煤柱影响巷道的稳定性问题,采用FLAC3D数值模拟的方法,对采空区巷道受2次采动和不同宽度煤柱影响下围岩的变形特征及应力分布规律进行研究,基于耦合支护技术提出了具体的支护方案。结果表明,底板岩层的应力分布受邻近采空区和煤柱叠加应力的影响,煤柱到采空区80 m范围内底板岩层受到剧烈影响,最大应力集中系数为3.9;当煤柱宽度增大时,巷道围岩塑性区随之减小。根据巷道的破坏特征及应力分布规律,提出“高强锚网索+浅深部围岩分次注浆加固+喷浆”分层耦合支护技术参数,在现场得到了成功应用。

Aiming at the stability of floor roadway affected by goaf and coal pillar,FLAC3D numerical simulation method was used to study the deformation characteristics and stress distribution law of surrounding rock in goaf under the influence of twice mining and coal pillar with different width,and a specific support scheme was proposed based on coupling support technology.The results show that the stress distribution of floor rock is affected by the superposition stress of adjacent goaf and coal pillar.The floor rock strata within 80 m from coal pillar to goaf is severely affected,and the maximum stress concentration factor is 3.9.When the width of coal pilar increases,the plastic zone of roadway surrounding rock decreases.According to the failure characteristics and stress distribution law of floor roadway,the layered coupling support technical parameters of"high-strength anchor mesh cable+sub grouting reinforcement of shallow and deep surrounding rock+shotcrete"are proposed,which have been successfully applied in the field.