Shaanxi Huangling No. 2 Coal Mine Co., Ltd.

为探究无煤柱自成巷在留巷过程中的顶板变形与应力演化规律,在理论层面以巷道围岩与支护系统力学模型作为研究的出发点,分析巷道围岩在顶板不同垮落阶段的变形特征,以黄陵二矿北二巷无煤柱自成巷工作面矿压监测数据为例进行工程验证。结果表明,无煤柱自成巷由巷道围岩、支护结构以及上覆岩层共同组成支护系统。巷道上方顶板破断共经历3个演化阶段,包括初始稳定阶段、剧烈变形阶段以及稳定压实阶段。影响巷道顶板下沉量的因素共有4个,当煤层厚度较低、顶板垮落高度较高、岩石碎胀系数较高、关键块长度越小时,顶板的下沉量将会降低。

In order to explore the roof deformation and stress evolution law of no-pillar self-formed roadway in the process ofretaining roadway, taking the mechanical model of roadway surrounding rock and support system as the theoretical startingpoint, the deformation characteristics of roadway surrounding rock in different roof caving stages are analyzed. The miningpressure monitoring data of north second roadway no-pillar self-formed roadway in Huangling No. 2 Coal Mine is taken as anexample for engineering verification. The results show that the self-formed roadway without coal pillar is composed of surrounding rock, supporting structure and overlying strata. The roof fracture above the roadway goes through three evolutionstages, including the initial stability stage, the intense deformation stage and the stable compaction stage. There are four factors affecting the subsidence of roadway roof. When the thickness of coal seam is low, the height of roof collapse is high, thecoefficient of rock crushing expansion is high, and the length of key block is smaller, the subsidence of roof will decrease.