• 中国科学引文数据库(CSCD)来源期刊
  • 中文核心期刊中文科技核心期刊
  • Scopus RCCSE中国核心学术期刊
  • 美国EBSCO数据库 俄罗斯《文摘杂志》
  • 《日本科学技术振兴机构数据库(中国)》
二维码

隧道建设(中英文) ›› 2022, Vol. 42 ›› Issue (S1): 28-39.DOI: 10.3973/j.issn.2096-4498.2022.S1.004

• 研究与探索 • 上一篇    下一篇

锁脚锚杆控制隧道初期支护沉降的原理和应用

剧仲林   

  1. (中铁十二局集团第四工程有限公司, 陕西 西安 710021
  • 出版日期:2022-07-22 发布日期:2022-08-22
  • 作者简介:剧仲林(1968—),男,陕西西安人,1992年毕业于石家庄铁道学院,铁道工程专业,本科,正高级工程师,现从事岩土工程、地下工程等领域的施工技术与科研工作。E-mail: juzhonglin681104@163.com。

Principle and Application of Foot Locking Bolt to Tunnel Primary Support Settlement Control

JU Zhonglin   

  1. (China Railway 12th Bureau Group Four Corporation Limited, Xi′an 710021, Shaanxi, China)
  • Online:2022-07-22 Published:2022-08-22

摘要: 当前软岩隧道初期支护因沉降变形量大而造成的成本消耗高问题较突出,初期支护底脚作用力与锁脚锚杆抗力不平衡是隧道初期支护沉降的主要原因,其中建立支护底脚与锁脚锚杆之间力的平衡关系是控制隧道初期支护沉降变形的重要前提。以弹性地基梁柱原理和摩擦桩原理来计算分析锁脚锚杆的内力和位移及其与地基的反力关系,以此确定锁脚锚杆的承载能力;通过分析锁脚锚杆对支护结构的柔度,确定其与支护结构的相互影响,进而建立考虑锁脚锚杆对支护结构底脚影响的支护结构力学计算模型,计算其作用于锁脚锚杆端上的作用力作为锁脚锚杆的设计依据;按照上述原理,分析了Ⅴ级围岩当前流行的42锁脚锚管的不足,并示例计算分析了108锁脚锚管的承载能力;最后以Ⅵ级围岩风积砂隧道施工的实例来说明“分布式”加强锁脚锚管以及锁脚锚桩控制支护沉降变形的显著效果验证技术的可行性;结论认为软岩隧道初期支护可按照“荷载—结构”原理确定围岩与支护、支护与锁脚锚杆之间的作用力与反作用力关系,达成支护结构之间力的平衡稳定以实现控制支护沉降的目的。

关键词: 隧道, 初期支护, 变形控制, 锁脚锚杆, 弹性地基梁柱, 摩擦桩, 弹性无铰拱, 直接弹性抗力, 加强锁脚, 锚桩

Abstract:  Presently, the cost consumption caused by large settlement deformation of primary support of soft rock tunnel is high. The imbalance between the force of primary support foot and the resistance of locking bolt is the main reason causes the settlement of primary support of tunnel. Hence, the force balance between primary support foot and locking bolt is an important premise to control the settlement deformation of primary support of tunnel. In this paper, based on the elastic foundation beam column principle and the friction pile principle, the internal force and displacement of the locking bolt and its reaction relationship with the foundation are calculated and analyzed, so as to determine the bearing capacity of the locking bolt. Then, by analyzing the flexibility of the locking bolt to the supporting structure, the interaction between the locking bolt and the supporting structure is determined, the mechanical calculation model of the supporting structure considering the influence of the locking bolt on the bottom foot of the supporting structure is established further, and the force acting on the end of the locking bolt is calculated as the design basis of the locking bolt. On this basis, the current popular problems of grade Ⅴ surrounding rock using 40 foot locking bolt are analyzed, and the bearing capacity of 108 foot locking bolt is analyzed through example calculation. Finally, taking the construction of grade surrounding rock aeolian sand tunnel as an example, the remarkable effect of distributed strengthened foot locking anchor pipe and pile on controlling support settlement and deformation is validated. It is concluded that the reaction between surrounding rock and support and that between support and foot locking bolt can be determined according to the principle of loadstructure method, so as to achieve the balance and stability of the force between support structures and further control the support settlement.

Key words: tunnel, primary support, deformation control, foot locking bolt, elastic foundation beam column, friction pile, elastic nonhinged hinged arch, direct elastic resistance, reinforced locking foot, anchor pile