相邻巷道断面形状选择及联合支护技术研究

Study on cross-section shape selection and combined support technology

为解决在高应力软岩条件下巷道围岩变形大、难支护等问题,以曙光矿2号煤为例,采用错层位外错式沿空掘巷布置方式。相邻巷道断面形状分别选取“矩形-矩形”、“矩形-异形”、“异形-异形”3种方式,采用数值模拟研究在下巷开挖后巷道围岩变形特征、围岩侧向支承压力分布和围岩塑性区分布规律。结果表明:“异形-异形”巷道相较于“矩形-异形”巷道和“矩形-矩形”巷道,其下巷巷道围岩位移、侧向支承应力和围岩塑性区都要小,故选择“异形-异形”巷道作为错层位外错式沿空掘巷巷道断面形状,相邻巷道间采用立体化联合支护技术,经现场监测,顶板最大下沉量为144 mm,底板最大鼓起量为91 mm,两帮最大移近量为315 mm,可减小下巷巷道围岩变形。

In order to solve the problems of large deformation and difficult support of roadway surrounding rock under the condition of high stress soft rock,No.2 coal of Shuguang Mine takeng as an example,the outside-type layout of roadway excavation was adopted.The section shapes of adjacent roadways were selected as“rectangular-rectangular”,“rectangular-special-shaped”and“special-shaped-special-shaped”respectively.Numerical simulation was used to study the deformation characteristics of surrounding rock,the distribution of lateral supporting pressure of surrounding rock and the distribution law of surrounding rock plastic zone after the excavation of the lower roadway.The results showed that the"special-shaped-special-shaped"roadway was smaller than the"rectangular-special-shaped"roadway and the"rectangular-rectangular"roadway,and the surrounding rock displacement,lateral support stress and plastic zone of the surrounding rock were the smallest.The shape-shaped roadway was used as the cross-section shape of the roadway along the roadway.Three-dimensional combined support technology was adopted between adjacent roadways,and through on-site monitoring,the maximum roof subsidence was 144mm,the maximum floor heave was 91mm,and the maximum displacement of two sides was 315mm,which reduced the deformation of surrounding rock in the lower roadway.