硬塑粉质黏土层深埋马蹄形隧道开挖土拱演化分析  

Evolution analysis of pressure-arch of deeply buried horseshoe tunnel in hard plastic silty clay layers

作　　者：刘金慧 屈克军 丁万涛[3,4] 王杨 LIU Jinhui;QU Kejun;DING Wantao;WANG Yang(School of Communications and Civil Engineering,Shandong Jiaotong University,Ji nan 250023,China;China Railway 14th Bureau Group Co.,Ltd.,Ji nan 250101,China;Geotechnical and Structural Engineering Research Center,Shandong University,Ji nan 250061,China;School of Qilu Transportation,Shandong University,Ji nan 250002,China)

机构地区：[1]山东交通学院交通土建工程学院,山东济南250023 [2]中铁十四局集团有限公司,山东济南250101 [3]山东大学岩土与结构工程研究中心,山东济南250061 [4]山东大学齐鲁交通学院,山东济南250002

出　　处：《人民长江》2022年第1期189-197,共9页Yangtze River

基　　金：国家自然科学基金项目(41572275)。

摘　　要：硬塑状粉质黏土地层深埋马蹄形隧道开挖易出现土拱效应。以改进的太沙基围岩压力理论为基础,对上述马蹄形隧道开展了数值计算和现场监测试验,分析隧道开挖全过程中围岩竖向应力重分布及地层沉降变化情况,得出压力拱的形成及演化规律,并分析围岩力学参数大小变化对压力拱形态的影响。研究结果表明:压力拱内围岩应力及地层沉降变化显著,可作为压力拱高度和形状的判断依据;压力拱的形成与发展主要集中在掌子面前后约1倍隧道洞径的距离,它主要分布在隧道上方90°的区域;压力拱高度随围岩黏聚力及内摩擦角的增大呈明显的减小趋势,但宽度对围岩力学参数变化不敏感。研究成果为确定硬塑状粉质黏土地层深埋马蹄形隧道的超前支护参数提供了参考,对指导隧道施工具有重要意义。The soil arching effect can be easily caused in excavation of deeply buried horseshoe tunnel in hard plastic silty clay layers.On the basis of Terzaghi rock mass pressure theory,we use numerical calculation and field monitoring test to study the vertical stress redistribution and stratum settlement variation during the whole process of tunnel excavation.The influence of mechanical parameters of surrounding rock and tunnel excavation on the morphology of soil arching is also analyzed.The result shows that rock stress and stratum settlement in soil arching can change significantly,which could describe the height and morphology of soil arching.The formation and development of soil arching effect mainly concentrated in area near tunnel face of 1 time of tunnel span,and in the range of upper 90°of tunnel vault.The height of soil arching decreased obviously with the increase of cohesion and internal friction angle of the surrounding rock,however the width of soil arching was not sensitive to the change of mechanical parameters of surrounding rock.The research results can provide a reference for determining the parameters of the advance support of deeply buried horseshoe tunnel in hard plastic silty layers,and are of great significance for guiding the tunnel construction.

关 键 词：马蹄形隧道 土拱效应 硬塑状粉质黏土地层 竖向应力 

分 类 号：U459.3[建筑科学—桥梁与隧道工程]