煤炭工程 ›› 2026, Vol. 58 ›› Issue (3): 94-103.doi: 10.11799/ce202603012

• 施工技术 • 上一篇    下一篇

厚煤层软岩临空巷道围岩塑性区演化规律及控制技术

丁自伟,冯 磊,张会宾,马 瑞,贾金兑,巩欣伟   

  1. 1. 西安科技大学 能源学院,陕西 西安 710054

    2. 陕西旬邑县旬东煤业有限责任公司,陕西 咸阳 711300

  • 收稿日期:2025-01-09 修回日期:2025-02-25 出版日期:2026-03-10 发布日期:2026-04-14
  • 通讯作者: 冯磊 E-mail:13984224532@163.com

Evolution Law and Control of Plastic Zone of Surrounding Rock in Soft Rock Mining Roadway of Thick Coal Seam

  • Received:2025-01-09 Revised:2025-02-25 Online:2026-03-10 Published:2026-04-14

摘要:

巷道围岩塑性区宽度是巷道支护参数设计的重要依据。为揭示巷道围岩变形破坏特征,采用理论分析、数值模拟与现场工业试验相结合的方法,系统研究了不同侧压系数和围岩岩性下巷道塑性区演化规律。结果表明:①随着侧压系数减小,塑性区形态依次从“圆形”向“类椭圆”“类蝶形”演化,最终发展为“蝶形”,不规则程度逐步增强;当侧压系数为0.8时,顶底板与两帮塑性区的分布形态及宽度趋于相近;在侧压系数0.2~1.0范围内,顶底板最大塑性区宽度依次为2.60.20.53.82.8m,最大变化率达95%,两帮最大塑性区宽度依次为7.34.65.85.82.8m,最大变化率为62%,顶底板塑性区变化幅度明显大于两帮。②围岩岩性主要影响塑性区发育范围,对塑性区形态无明显作用;围岩岩性越优、整体强度越高,塑性区发育范围越小,细粒砂岩中塑性区宽度显著小于煤层;所有岩性条件下,巷道塑性区破坏均以剪切破坏为主,且两帮变形量大于顶底板变形量;不同岩性下,顶底板塑性区宽度最大变化率为65%,两帮为68%,二者变化幅度基本一致。③依据塑性区发育规律,对巷道采用高预紧力锚杆(索)支护,并通过增大杆体直径、延长杆体长度提升支护体系强度与延伸率。现场试验表明:优化支护方案可有效控制围岩离层与破坏变形,围岩变形量控制在300mm以内,巷道围岩稳定性显著提升。

关键词: 软岩巷道, 塑性区, 侧压系数, 围岩性质, 围岩控制, 数值模拟, 支护优化

Abstract:

The width of the plastic zone in the vicinity of rock around a roadway is a crucial factor for determining the support design parameters. This study investigates the deformation and failure patterns of the rock surrounding the roadway by examining the effects of varying lateral pressure coefficients, rock types, and depths of roadway burial through theoretical analysis, numerical simulation, and field testing. The findings reveal several key points : (1) With lateral pressure coefficient as the variable, the plastic zone's irregularity around the roadway increases as the coefficient decreases. The shape of the plastic zone evolves from circular to elliptical, then to a butterfly pattern, and finally stabilizes in a butterfly form. The plastic zone at the roof and floor narrows while that at the sides widens, with the roof and floor changes being more pronounced. At a lateral pressure coefficient of 0.8, the plastic zone's distribution and width at the roof, floor, and sides of the roadway are similar. (2) When considering rock type, the plastic zone width in fine-grained sandstone is significantly less than in coal seams. The stronger the overall rock, the smaller the plastic zone's failure width. Shear failure is the primary mode of plastic zone failure, with greater deformation at the sides compared to the roof and floor. Different rock types influence the plastic zone's width but not its shape. (3) Based on the plastic zone's growth pattern in the rock surrounding the roadway, the use of high pre-stressed bolts (or cables) is recommended, with extended lengths and increased diameters to enhance the elongation and strength of the bolts (or cables). Field tests indicate that the optimized support system effectively manages the separation and deformation failure of the roadway. The rock's deformation is kept within 300 mm, significantly enhancing its internal stability and reducing roadway deformation.

中图分类号: