上软下硬复合地层土压平衡盾构双线施工土体变形规律研究  

Study on soil deformation law of double-line construction of earth pressure balance shield in upper-soft and lower-hard composite stratum

作　　者：杜金鹏 陈鹏飞 赵世森 Du Jinpeng;Chen Pengfei;Zhao Shisen(First Mechanized Construction Branch of China Railway Shanghai Engineering Group Co.,Ltd.,Nanjing Jiangsu 211102,China;State Key Laboratory of Intelligent Construction and Healthy Operation and Maintenance of Deep Underground Engineering,China University of Mining and Technology,Xuzhou Jiangsu 221116,China)

机构地区：[1]中铁上海工程局集团有限公司第一机械化施工分公司,江苏南京211102 [2]中国矿业大学深地工程智能建造与健康运维全国重点实验室,江苏徐州221116

出　　处：《山西建筑》2025年第8期159-163,169,共6页Shanxi Architecture

摘　　要：上软下硬复合地层作为盾构施工中的特殊地质,同时具有软岩地层稳定性差和硬岩地层强度高的特点。以济南地铁6号线某盾构区间为施工背景,采用FLAC3D基于土体特性建立盾构掘进精细化数值模型,分析了开挖过程中土体变形规律,研究了管片顶部与底部最大主应力和最小主应力变化情况。结果表明:双线隧道掘进后,地表最大沉降量位于各隧道上方地表,并沿两边逐渐减小,地表沉降曲线大致呈“W”形,总体呈对称分布;随着开挖面土岩比例的不断增加,地表变形值逐渐增大,两隧道中心线处地表沉降相比于左右两条总体略小;隧道拱顶处最大主应力与最小主应力随着土岩比的增大而不断减小,拱底处最大主应力与最小主应力随着土岩比的增大而增大。As a special geology in shield construction,the upper soft and lower hard composite stratum has the characteristics of poor stability of soft rock stratum and high strength of hard rock stratum.In this paper,a shield section of Jinan Metro Line 6 is taken as the construction background.FLAC3D is used to establish a fine numerical model of shield tunneling based on soil characteristics,and the deformation law of soil during excavation is analyzed.The changes of the maximum principal stress and the minimum principal stress at the top and bottom of the segment are analyzed.The results show that after the double-track tunnel is excavated,the maximum surface settlement is located on the surface above each tunnel and gradually decreases along both sides.The surface settlement curve is roughly‘W’shaped and symmetrically distributed.With the increase of the proportion of soil and rock on the excavation surface,the surface deformation value increases gradually,and the surface settlement at the center line of the two tunnels is slightly smaller than that of the left and right tunnels.The maximum principal stress and minimum principal stress at the vault of the tunnel decrease with the increase of the soil-rock ratio,and the maximum principal stress and minimum principal stress at the arch bottom increase with the increase of the soil-rock ratio of the tunnel.

关 键 词：上软下硬地层 土压盾构 数值模拟 土体变形规律 双线施工 

分 类 号：TU997[建筑科学—市政工程] U455.43[建筑科学—桥梁与隧道工程]