厚煤层超高巷道支护技术

以山西某矿超高回采巷道为研究对象,数值演算了巷道高3.5⁷.5 m围岩响应特征:巷帮剪、拉塑性区深度与巷道高度大致呈正比关系,巷高对两帮移近量影响最大,且巷帮垂直应力峰值内移.阐明了巷帮为超高巷道围岩控制的关键部位,最终采用了高强度、高黏结力、高预紧力、高可靠性锚杆与帮斜拉锚索梁联合支护技术.巷道掘出后两帮和顶底最大相对移近速度分别是7,3 m/d,15 d后稳定,移近速度降低至1.5 mm/d以下,经过120 d观测,两帮相对移近量125 mm,顶底板相对移近量88 mm.工程实践结果验证了该类型超高巷道支护的指导思想和支护技术的科学性,以期为类似条件下超高巷道支护提供借鉴.

Support technology of ultra-high roadway in thick coal seam

Based on the ultra-high mining roadway appeared in a Shanxi mine,the response characteristic in a change process of height from 3.5 m to 7.5 m is simulated in surrounding rock.Results are as follows： shear and tensile plastic zone depth in sides is proportional to the roadway height; the higher roadway,the roadside relative convergence is bigger and the relative convergence of floor-roof is less side; the vertical stress peak moves deeper.Bolt support technology with high-strength,high-bond force,high-pre-tightening force,and high-reliability could better enhance the carrying capacity of an anchoring structure,and diagonal cablebeam are anchoraged in a shoulder stable area,which is stable and reliable.After the roadway is dug out,the maximum relative convergence speed of side-side and roof-floor are 7 mm/d and 3 mm/d,below 1.5 mm/d when it achieves self-stability after 15 days.The total relative convergence of side-side is 125 mm and rooffloor relative convergence is 88 mm during the observation of 120 days.