浅埋暗挖隧道杂填土地层钢管桩加固机理研究  

Study on Reinforcement Mechanism of Steel Pipe Pile for Shallow Mined Tunnels in Miscellaneous Fills

作　　者：张安睿[1] 张建国 马超 ZHANG Anrui;ZHANG Jianguo;MA Chao(Guizhou Transportation Planning Survey and Design Institute of Limited Co.,Ltd.,Guiyang 550000;Changsha Road and Bridge Branch of China Railway Sixth Group Co.,Ltd.,Changsha 410007)

机构地区：[1]贵州省交通规划勘察设计研究院股份有限公司,贵阳550000 [2]中铁六局集团有限公司长沙路桥分公司,长沙410007

出　　处：《现代隧道技术》2020年第S01期165-173,共9页Modern Tunnelling Technology

基　　金：贵州省科技攻关计划(黔科合重大专项字[2018]3011).

摘　　要：杂填土地层的加固对浅埋暗挖隧道的施工安全具有重要的影响。文章依托双柏隧道工程展开了浅埋暗挖隧道杂填土地层钢管桩的加固机理研究,利用有限元数值软件对钢管桩加固杂填土地层的加固机理进行了数值模拟研究,并通过现场测试对加固后隧道的安全性进行相关分析。结果表明:(1)采用钢管桩加固杂填土区可有效减小地表沉降及隧道变形值,保证开挖隧道的稳定性;(2)钢管桩加固后可有效阻断岩层位移的发展及围岩塑性区的发展,提高围岩的承载能力;(3)不同的开挖工序对于地表沉降及支护结构安全性的影响不同,采用预留核心土法施工时,下台阶的开挖对于隧道整体的安全性及地表沉降具有重要的影响作用,在施工时应当予以高度重视;(4)通过对锚杆轴力、钢架应力及喷射混凝土应力的现场测试分析,支护结构均处于安全状态。The reinforcement of the miscellaneous fills has an important influence on the construction safety of the shallow mined tunnel.In this paper,in order to study the reinforcement mechanism of the steel pipe pile for the shallow buried tunnel in the miscellaneous fills,the relevant research is carried out based on the Shuangbai tunnel project.The finite element numerical analysis software is used to simulate the mechanical properties of the reinforced miscellaneous fills,and the safety analysis of the reinforced tunnel is carried out by site testing.The results show that:(1)using steel pipe piles to reinforce the miscellaneous fills can effectively reduce the ground settlement and tunnel deformation values,guaranteeing the stability of the excavated tunnel;(2)the steel pipe pile can effectively block the development of displacement and the plastic zone of surrounding rocks,ensuring the stability of surrounding rocks and improving the bearing capacity of surrounding rocks;(3)different excavation procedures have different effects on the surface settlement and the safety of the supporting structure,when the bench construction method with reserved core soil is adopted,the excavation of the lower bench has an important effect on the overall safety of the tunnel and the surface settlement,and it should pay attention to this during construction;(4)the testing of the axial force of the bolt,the stress of the steel arch and the stress of the shotcrete on the site shows that the supporting structure is in a safe state.

关 键 词：浅埋暗挖隧道 杂填土层 钢管桩 加固机理 数值模拟 现场实测 

分 类 号：U451[建筑科学—桥梁与隧道工程]