隧道机械化大断面进洞施工与加固措施研究  

Research on Mechanical Entry Excavation and Reinforcement Measures for Large Cross-Section Tunnel

作　　者：梁肖 李科[1,2] 郭鸿雁[2] 胡学兵[2] 姚成睿[2] LIANG Xiao;LI Ke;GUO Hongyan;HU Xuebing;YAO Chengrui(School of Civil Engineering,Chongqing Jiaotong University,Chongqing 400074,China;China Merchants Chongqing Communications Technology Research&Design Institute Co.,Ltd.,Chongqing 400067,China)

机构地区：[1]重庆交通大学土木工程学院,重庆市400074 [2]招商局重庆交通科研设计院有限公司,重庆市400067

出　　处：《中外公路》2025年第1期186-195,203,共11页Journal of China & Foreign Highway

基　　金：青海省科技计划项目(编号:2023-SF-127)。

摘　　要：随着隧道施工技术与机械装备的创新发展,山岭隧道机械化钻爆施工已逐步发展起来,但山岭隧道机械化进洞施工时存在受地质因素影响大、设备适应性不高、作业空间受限等问题。该文以某隧道工程为依托项目,借助FLAC^(3D)有限差分软件对洞口浅埋段机械化大断面施工开挖方法和辅助加固措施进行了研究。对比分析了洞口浅埋段采用微台阶法施工时,不同循环进尺以及在不同掌子面进尺时掌子面加固前后的围岩位移、支护结构受力以及围岩塑性区的变化情况。研究结果表明:在不进行掌子面加固时,为保证施工安全,隧道洞口段机械化开挖循环进尺应控制在1.2 m以内,且保证超前管棚的搭接长度不小于3 m;若施工时加大循环进尺,则须对掌子面进行加固,在使用长10 m、间距1.5 m梅花形布置的玻璃纤维锚杆加固掌子面条件下,循环进尺最多可提高到1.8 m。With the innovation of tunnel construction techniques and mechanical equipment,mechanical drilling and blasting for mountain tunnels have gradually developed.However,several challenges exist during the mechanical entry excavation for mountain tunnels,including the significant influence of geological factors,limited equipment adaptability,and constrained working space.This research,based on a specific tunnel project,utilized FLAC^(3D) finite difference software to study the mechanical excavation method and auxiliary reinforcement measures for shallow-buried segments at the large cross-section tunnel portal.A comparative analysis was conducted on the displacement of surrounding rock,the stress of supporting structures,and the variation of plastic zones before and after tunnel face reinforcement for different advances per cycle and faces when employing a micro-step construction method.The findings indicate that without face reinforcement,to ensure construction safety,the mechanical excavation advance in the tunnel portal should be controlled within 1.2 m per cycle,and the overlapping length of the forepoling pipes should be no less than 3 m.When increasing the advance per cycle,tunnel face reinforcement is necessary.With the use of 10-meter-long and 1.5-meter-spaced fiberglass anchors arranged in a honeycomb pattern to reinforce the tunnel face,the maximum advance per cycle can be increased to 1.8 m.

关 键 词：隧道工程 机械化开挖 洞口浅埋段 循环进尺 辅助加固措施 

分 类 号：U455[建筑科学—桥梁与隧道工程]