Ground response of a gob-side gateroad suffering mining-induced stress in an extra thick coal seam
Ground response of a gob-side gateroad suffering mining-induced stress in an extra thick coal seam
复制标题
超厚煤层采动应力作用下沿空巷道的地面响应
DOI：
10.12989/gae.2020.22.1.001
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发表时间：
2020
影响因子：
3.2
通讯作者：
Bangyou Jiang
中科院分区：
文献类型：
--
作者：
Fulian He;Sheng Gao;Guangchao Zhang;Bangyou Jiang
本文研究了21m厚煤层开采引起的采动应力作用下沿空巷道的地表响应。首先在8209尾门进行了现场观测，包括巷道收敛和应力变化监测。巷道收敛观测结果表明，在相邻盘区8210撤退期间，采空区巷道变形经历了一个持续增长阶段、随后的加速增长阶段、最后的缓慢增长阶段。然而，在目前的8209板撤退期间，发生了强烈的地面反应，包括屋顶弯曲变形、肋骨挤出和底鼓，最大底鼓达到1530 mm。两排煤体内部的应力变化表明，卸荷始终位于应力集中区域，这是导致8209尾板反应强烈的原因。随后，提出了一种水力压裂技术来预裂后挡板8209上方的两个坚硬顶板，从而减小了对后挡板的诱导扰动。通过现场应用，验证了上述顶板处理的有效性。本文的研究成果对了解特厚煤层开采沿空巷道稳定性控制具有一定的参考价值。
This paper presents an investigation of the ground response of a gob-side gateroad suffering mining stress induced by a 21 m-thick coal seam extraction. A field observation, including entry convergence and stress changes monitoring, was first conducted in the tailgate 8209. The observation results of entry convergence showed that, during the adjacent panel 8210 retreating period, the deformation of the gob-side gateroad experienced a continuous increase stage, subsequently, an accelerating increase stage, and finally, a slow increase stage. However, strong ground response, including roof bending deflection, rib extrusion and floor heave, occurred during the current panel 8209 retreating period, and the maximum floor heave reached 1530 mm. The stress changes within coal mass of the two ribs demonstrated that the gateroad was always located in the stress concentrated area, which responsible for the strong response of the tailgate 8209. Subsequently, a hydraulic fracture technique was proposed to pre-fracture the two hard roofs above the tailgate 8209, thus decreasing the induced disturbance on the tailgate. The validity of the above roof treatment was verified via field application. The finding of this study could be a reference for understanding the stability control of the gob-side gateroad in extra thick coal seams mining.