长江科学院院报 ›› 2023, Vol. 40 ›› Issue (8): 97-104.DOI: 10.11988/ckyyb.20220326

• 岩土工程 • 上一篇    下一篇

隧道穿越突出煤层预留安全岩柱失稳分析方法

李永靖1, 王松1, 印建文2, 文成章1, 程耀辉1   

  1. 1.辽宁工程技术大学 土木工程学院,辽宁 阜新 123000;
    2.成兰铁路有限责任公司,成都 610000
  • 收稿日期:2022-03-30 修回日期:2022-05-12 出版日期:2023-08-01 发布日期:2023-08-09
  • 通讯作者: 王 松(1995-),男,河南濮阳人,硕士研究生,主要从事隧道工程及地下空间方向的研究。E-mail:wangs_kb@163.com
  • 作者简介:李永靖(1976-),男,山东烟台人,教授,博士,博士生导师,主要从事岩土工程方面的教学和科研工作。E-mail:Lyjsdyt@126.com
  • 基金资助:
    国家自然科学基金项目(51974146,52174078)

A Method of Analyzing the Instability of Reserved Safety Rock Pillar for Tunnel Crossing Outburst Coal Seam

LI Yong-jing1, WANG Song1, YIN Jian-wen2, WEN Cheng-zhang1, CHENG Yao-hui1   

  1. 1. School of Civil Engineering, Liaoning Technical University, Fuxin 123000, China;
    2. Chenglan Railway Co., Ltd., Chengdu 610000, China
  • Received:2022-03-30 Revised:2022-05-12 Published:2023-08-01 Online:2023-08-09

摘要: 针对隧道穿越突出煤层掌子面前方预留安全岩柱极易发生失稳破坏,导致煤与瓦斯突出的重难点问题,基于突变理论分析,综合运用Polynomial分布函数和二分法,提出了一种判别隧道穿越突出煤层预留安全岩柱失稳的分析方法。根据总势能原理,建立岩柱失稳尖点突变模型,推导出岩柱失稳力学判据;结合围岩塑性屈服区体积突变判据,建立岩柱稳定性预测模型,得到岩柱稳定性判别式,并依托工程实例验证分析。结果表明:隧道穿越突出煤层预留安全岩柱稳定性与岩柱的弹性模量E、厚度L、垂直地应力N、开挖面等效高度H密切相关;基于屈服体积突变判据建立的岩柱稳定性预测模型和失稳力学判据合理可行;岩柱稳定性判别结果与现场施工情况一致,验证了所提出的预测方法与失稳判据的合理性及准确性,具有工程实用价值。

关键词: 穿煤瓦斯隧道, 岩柱失稳, 突变理论, 预测模型, 突变判据

Abstract: The instability and failure of reserved safety rock pillars in tunnels crossing through outburst coal seam faces often lead to coal and gas outbursts. Based on catastrophe theory, we propose an analytical method for assessing the stability of reserved safety rock pillars in such tunnels by using Polynomial distribution functions and dichotomy in a comprehensive manner. By applying the principle of total potential energy, we establish a cusp catastrophe model to represent rock pillar instability, from which a mechanical criterion for rock pillar instability is derived. To further account for the volume catastrophe criterion of the plastic yield zone of surrounding rock, we establish a predictive model for rock pillar stability and obtain a discriminant for assessing rock pillar stability. Engineering examples are employed to verify and analyze the proposed method. Results demonstrate that the stability of reserved safety rock pillars in gas tunnels crossing coal seam is closely correlated with elastic modulus E, thickness L, vertical in-situ stress N, and equivalent height H of tunnel excavation face. The predictive model based on the yield volume catastrophe criterion, as well as the mechanics criterion for stability and instability, exhibits reasonable and feasible outcomes. The discriminant results for rock pillar stability align with the actual on-site conditions, thereby validating the rationality and accuracy of our proposed prediction method and criteria.

Key words: gas tunnel crossing coal seam, rock pillar instability, catastrophe theory, prediction model, catastrophe criterion

中图分类号: