富水砂卵石地层泥水盾构施工地层变形规律  

Deformation Law of Water-rich Sandy Gravel Stratum Induced by Slurry Shield Driving

作　　者：王振飞[1] 张成平[1] 王剑晨[1] 

机构地区：[1]北京交通大学,北京100044

出　　处：《铁道工程学报》2013年第9期78-83,共6页Journal of Railway Engineering Society

基　　金：国家科技支撑计划项目(2012BAJ01B03);国家自然科学基金项目(51008015);中央高校基本科研业务费专项资金项目(2012JBZ013)

摘　　要：研究目的:富水砂卵石地层颗粒间空隙大、无黏聚力且灵敏度高,在此类地层进行大直径盾构隧道施工所引起的地层变形规律尚不明确。本文以北京地下直径线为依托,通过对地表沉降和深部土体水平位移的实测和分析,得出富水砂卵石地层盾构隧道施工引起地层变形的基本规律。研究结论:(1)通过对盾构刀盘改造,可使富水砂卵石地层泥水盾构施工引起的地表沉降显著降低,隧道两侧深部土体的水平位移也相应降低,说明合理的盾构刀盘设计对富水砂卵石地层变形控制至关重要;(2)盾构隧道掘进过程中,最大沉降发生在盾构通过阶段,地表沉降的纵向影响范围约为盾构隧道工作面前方1.25倍隧道洞径和工作面后方4.15倍隧道洞径;(3)盾构刀盘改造前后,Peck公式均可以很好地拟合地表沉降槽曲线,但地层损失率和沉降槽宽度系数有一定变化;(4)研究成果可为类似工程提供借鉴及参考。Research purposes： The laws of strata deformation induced by large diameter shield driving in the water - rich sandy gravel stratum are not clearly known due to the large gap between particles, none cohesion and the high sensitivity in this stratum. Based on the Beijing underground diameter line project, the surface subsidence and horizontal displacement of the deep soil were measured and analyzed to know the laws of strata deformation induced by shield tunnel driving in the water- rich sandy gravel stratum. Research conclusions： Before remolding of the shield cutter head, the maximum surface subsidence was about 17.0 ram, the transverse influence range of the surface subsidence was about 40 m on each side of the tunnel centerline, the longitudinal influence range of the surface subsidence was about 1.25 times of the tunnel diameter in front of the tunnel working face and 4.15 times of the tunnel diameter in rear of the tunnel working face and the maximum transverse and longitudinal displacements values of the deep soil on both sides of the tunnel were 11.0 mm and 6.8 mm respectively on the horizontal plane of the tunnel center. After remolding of the shield cutter head, the maximum surface subsidence was reduced to 8.0 mm or below and the horizontal displacements of the deep soil on both sides of the tunnel were also reduced. It can be seen the the surface subsidence can be effectively controlled by remolding of the shield cutter head. The peck equation matched the surface groove curve before and after the remolding of the shield cutter head. However the changes took place in the strata ioss rate and width coefficient of settlement trough. This research results can provide reference to the similar projects.

关 键 词：隧道工程 泥水盾构施工 富水砂卵石 地层变形 现场实测 PECK公式 

分 类 号：U25[交通运输工程—道路与铁道工程]