不同跨径小净距隧道管棚超前支护机理与变形控制
Advance Support Mechanism and Deformation Control of Pipe Shed in Small Clear Distance Tunnels with Different Spans
黄光友 1肖鹏帅 2李明珠 3李文杰 2梁斌2
作者信息
- 1. 中交二公局第四工程有限公司,洛阳 471013;河南科技大学 土木建筑学院,洛阳 471023
- 2. 河南科技大学 土木建筑学院,洛阳 471023
- 3. 中交二公局第四工程有限公司,洛阳 471013
- 折叠
摘要
以新疆乌尉高速公路上新光隧道工程为依托,对不同跨径软弱围岩小净距隧道超前支护力学特性进行研究.采用有限元软件MIDAS GTS NX建立有无管棚超前支护两种工况下隧道模型,分析不同开挖阶段管棚弯矩的分布规律以及两种工况下隧道拱顶沉降、初期支护应力及围岩塑性区的变化规律.结果表明:在隧道开挖过程中,掌子面处管棚受力较大,支护稳定后受力较小且较为均匀;管棚超前支护工况下累计拱顶沉降左洞为2.83 mm、右洞为6.74 mm,相较无超前支护,左、右洞拱顶沉降分别减少了34.64%和32.26%;布设管棚后衬砌最大主应力降低14.13%,围岩最大塑性应变减少了28.48%.采用管棚超前支护措施进行洞口段开挖能提高围岩稳定性,控制围岩变形,可为类似工程提供指导借鉴.
Abstract
Based on Shangxinguang Tunnel project of Wuwei expressway in Xinjiang,mechanical characteristics of advanced support of small clear distance tunnel in soft surrounding rock with different spans are studied.The finite element software MIDAS GTS NX is used to establish tunnel models under two working conditions with or without pipe shed advanced support.The distribution law of pipe shed bending moment at different excavation stages and the change law of tunnel vault settlement,initial support stress and plastic zone of surrounding rock are analyzed under two working conditions.The results show that:in the process of tunnel excavation,the stress of pipe shed at the palm surface is larger,and the stress is smaller and more uniform after the support is stabilized.The cumulative arch settlement in the left and right tunnels is 2.83mm and 6.74mm respectively.Compared with no advance support,the arch settlement in the left and right tunnels decreases by 34.64%and 32.26%respective-ly.The maximum principal stress of lining decreases by 14.13%and the maximum plastic strain of surrounding rock decreases by 28.48%.Using pipe shed advanced support measures to excavate the entrance section can im-prove the stability of surrounding rock,control the deformation of surrounding rock,ensure the safety of tunnel construction,and provide guidance and reference for subsequent similar projects.
关键词
不同跨径小净距隧道/管棚超前支护/Winkler弹性地基梁理论/变形控制Key words
tunnel with different spans and small clear distance/pipe shed support/Winkler elastic foundation beam theory/deformation control引用本文复制引用
基金项目
国家自然科学基金(U1604135)
中交第二公路工程局有限公司重点科技研发项目(RP2022011745)
河南省科技厅产学研合作项目(2015HNCXY011)
出版年
2024
NETL
NSTL
万方数据