东北大学学报(自然科学版) ›› 2022, Vol. 43 ›› Issue (10): 1469-1476.DOI: 10.12068/j.issn.1005-3026.2022.10.014

• 资源与土木工程 • 上一篇    下一篇

原位扩建既有隧道主洞与竖井交叉段扩建型式

王鑫, 赵文, 柏谦   

  1. (东北大学 资源与土木工程学院, 辽宁 沈阳110819)
  • 修回日期:2021-10-11 接受日期:2021-10-11 发布日期:2022-11-07
  • 通讯作者: 王鑫
  • 作者简介:王鑫(1996-),男,内蒙古包头人,东北大学博士研究生; 赵文(1962-),男,辽宁沈阳人,东北大学教授,博士生导师.
  • 基金资助:
    国家自然科学基金资助项目(51878127).

Expansion Type of In-situ Expansion of the Intersection Between Main Tunnel and Shaft in the Existing Tunnel

WANG Xin, ZHAO Wen, BAI Qian   

  1. School of Resources & Civil Engineering, Northeastern University, Shenyang 110819, China.
  • Revised:2021-10-11 Accepted:2021-10-11 Published:2022-11-07
  • Contact: ZHAO Wen
  • About author:-
  • Supported by:
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摘要: 为了深入探究原位扩建既有隧道主洞与竖井交叉段的最优扩建型式,依托南岭隧道原位扩建工程,针对竖井与隧道主洞交叉段的扩建过程建立三维有限元模型,并研究单侧扩建、双侧扩建型式下围岩变形及应力随开挖过程的变化规律.考虑竖井与隧道的空间位置关系,基于太沙基理论提出不同扩建型式的隧道围岩压力计算公式.结果表明:两种扩建型式下围岩的变形速率均在掌子面距竖井与隧道交叉断面1倍洞径以内时较大;单侧扩建使围岩应力释放不均并形成偏压效应,产生较双侧扩建更大的围岩应力;扩建型式的选择对围岩压力的分布影响较大,围岩级别在Ⅲ~Ⅴ级时,围岩压力计算值由大到小排序为双侧扩建>太沙基理论>单侧扩建.

关键词: 隧道工程;原位扩建;扩建型式;数值模拟;围岩压力

Abstract: In order to explore the optimal in-situ expansion type of the intersection of the main tunnel and the shaft in the existing tunnel, a three-dimensional finite element model of the expansion process at the intersection of the main tunnel and the shaft was established based on the in-situ expansion project of the Nanling tunnel, and the changes of surrounding rock deformation and stress with the excavation process under the single-side expansion and double-side expansion were studied. Considering the spatial position relationship between the shaft and the tunnel, formulas for calculating the pressure of the surrounding rock of the tunnel with different expansion types were proposed based on Terzaghi′s theory. The results show that the deformation rate of surrounding rock within 1 time of the tunnel diameter between the tunnel face and the cross section of the shaft and the tunnel is larger. The single-side expansion makes the surrounding rock stress release unevenly and form a bias effect, causing a larger surrounding rock stress than that of the double-side expansion. The choice of expansion type has a great influence on the distribution of surrounding rock pressure, when the surrounding rock is in grade Ⅲ~Ⅴ, the calculated value of the surrounding rock pressure formula are the largest of the double-side expansion, followed by the Terzaghi′s theory, and the smallest for the single-sided expansion.

Key words: tunnel engineering; in-situ expansion; expansion type; numerical simulation; surrounding rock pressure

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