沿空巷道切顶卸压煤柱宽度与巷道底鼓变形关系研究

Study on the Relationship Between the Coal Pillar Width and the Deformation of Roadway Floor Heave Under Roof Cutting and Pressure Relief in Gob-Side Roadway

为探究侧向切顶条件下沿空护巷煤柱宽度变化对巷道底板的影响,通过理论计算、数值模拟和现场试验等对泊江海子矿某工作面的回采巷道展开了研究,构建了沿空巷道力学模型,得出巷道底板的应力和位移解析式;利用FLAC3D软件模拟了不同煤柱宽度条件下的底板受力情况。结果表明:沿空巷道底板应力由单峰三角形形态变为单峰梯形形态,峰值由实体煤侧逐渐向煤柱靠近采空区侧偏移,并且呈现出先增大后减小的趋势;巷道底板底鼓量随着煤柱宽度的增加逐渐减少,减少速率逐渐降低;工程试验结果表明,采用侧向切顶、联合支护以及加固底角控制技术可以有效减少底鼓量,从而提高了生产效率、保障了安全系数,为类似工况工作面煤柱宽度设计提供了参考。

In order to explore the influence of coal pillar width change on roadway floor under the condition of lateral roof cutting,the mining roadway of a working face in Bojianghaizi Mine was studied by theoretical calculation,numerical simulation and field experiment.The mechanical model of gob-side roadway was constructed,and the analytical formulas of stress and displacement of roadway floor were obtained.The FLAC3Dsoftware was used to simulate the stress of the floor under different coal pillar width conditions.The results show that the floor stress of gob-side roadway is asymmetrically distributed.With the increase of the coal pillar width,the right single-peak triangle shape of the floor stress changes into single-peak trapezoidal shape,and the peak value gradually shifts from the solid coal side to the coal pillar near the goaf side,and shows a trend of increasing first and then decreasing.The amount of floor heave in the roadway floor gradually decreases with the increase of coal pillar width,and the reduction rate gradually decreases.The engineering test results show that the use of lateral roof cutting,combined support and reinforcement bottom angle control technology can effectively reduce the amount of floor heave,thus improving the production efficiency and ensuring the safety factor,which provides a reference for the design of coal pillar width in similar working conditions.