煤炭工程 ›› 2024, Vol. 56 ›› Issue (4): 112-118.doi: 10. 11799/ ce202404017

• 研究探讨 • 上一篇    下一篇

近距离下煤层中空注浆锚索注浆前后周边剪应力作用机理

吴晓宇,周豪,吴晓伟   

  1. 1. 山西大同大学,山西 大同 037009 2. 晋能控股煤业集团 永定庄煤业有限责任公司,山西 大同 037000
  • 收稿日期:2023-10-24 修回日期:2024-01-21 出版日期:2023-04-20 发布日期:2024-12-09
  • 通讯作者: 吴晓伟 E-mail:798778008@qq.com

Action mechanism of peripheral shear stress before and after grouting with bolting cable in hollow seam under short distance

  • Received:2023-10-24 Revised:2024-01-21 Online:2023-04-20 Published:2024-12-09

摘要:

为解决近距离下煤层破碎巷道围岩难以控制的问题,基于理论分析和数值模拟研究中空注浆锚索注浆前后对破碎围岩的控制效果, 即注浆前后中空注浆锚索与围岩的周边剪应力作用机理。结果表明:注浆前锚固段符合粘弹性本构模型,剪应力曲线呈现线性增加到非线性下降再到稳定的单峰值,注浆后巷道周围预应力场沿锚索形成一个渐变式的整体,使巷道围岩应力场重新分布,剪应力强度随之降低,应力曲线转变二次线性快速增加到非线性快速下降再到稳定的双峰值曲线,有效提高破碎围岩和软岩巷道的抗剪强度。

关键词: 中空注浆锚索 , 破碎围岩剪应力 , 作用机理 , 巷道支护 , 应力控制

Abstract:

In order to solve the problem of difficult control of surrounding rock in broken roadway of coal seam in short distance, the control effect of surrounding rock before and after grouting with hollow grouting cable was studied based on theoretical analysis and numerical simulation, that is to say, the mechanism of the surrounding shear stress between the hollow grouting anchor cable and the surrounding rock before and after grouting. The results show that the pre-grouting anchorage section conforms to the viscoelastic constitutive model, and the shear stress curve increases linearly to a nonlinear decrease and then to a stable single peak, after grouting, the pre-stress field around the roadway forms a gradual whole along the anchor cable, which redistributes the stress field around the roadway and reduces the shear stress strength, the stress curve changes from quadratic linear to nonlinear and then to stable double peak curve, which can effectively improve the shear strength of broken surrounding rock and soft rock roadway.

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