Yin Shuaifeng, Zheng Xinjian, Wang En, Kang Qingtao, Zhang Xiaoming
School of Mine Safety, North China Institute of Science and Technology, Langfang, 065201, China.
School of Energy and Mining Engineering, China University of Mining & Technology-Beijing, Beijing, 100083, China.
Sci Rep. 2023 Oct 28;13(1):18527. doi: 10.1038/s41598-023-45857-y.
In response to the control problems of large-deformation roadways in close-distance coal seams, taking a typical roadway under irregular goafs and residual coal pillar in deep close-distance coal seams as the background, the characteristics of mine pressure and key difficulties in surrounding rock control of roadway are explored and an improvement strategy for controlling surrounding rock is proposed. The stress expression in roadway floor under the influence of residual coal pillar is derived by theoretical calculation. The peak lines of deviatoric stress and vertical stress in roadway after the mining of the upper coal seam are obtained by numerical simulation. The roadway is divided into two key zones: ordinary zone and disturbance zone by residual coal pillar, and the disturbance range of roadway below residual coal pillar is determined to be 44.60 m. It reveals the differential, asymmetric, and non-uniform distortion and failure laws of roadway at different positions under irregular goafs and residual coal pillar. The differential control technology named asymmetric support in ordinary zone of roadway and combined support and drilling pressure relief in disturbance zone below residual coal pillar is proposed. The feasibility of differential pressure relief and control technology has been verified through on-site engineering test, which ensures the safety and stability of roadway and provides technical references for surrounding rock control in similar deep and complex roadways.
针对近距离煤层大变形巷道的控制难题，以深部近距离煤层不规则采空区和残留煤柱下的典型巷道为背景，探究了巷道矿压显现特征及围岩控制的关键难点，提出了巷道围岩控制的改进策略。通过理论计算推导了残留煤柱影响下巷道底板的应力表达式。通过数值模拟得出了上煤层开采后巷道内偏应力和垂直应力的峰值线。将巷道按残留煤柱划分为普通区和扰动区两个关键区域，确定残留煤柱下方巷道的扰动范围为44.60 m。揭示了不规则采空区和残留煤柱影响下巷道不同位置的差异化、非对称、不均匀变形破坏规律。提出了巷道普通区非对称支护、残留煤柱下方扰动区联合支护与钻孔卸压的差异化控制技术。通过现场工程试验验证了差异化卸压控制技术的可行性，确保了巷道的安全稳定，为类似深部复杂巷道的围岩控制提供了技术参考。
