摘要
研究目的:小半径曲线盾构隧道施工引起的地表变形规律与盾构直线掘进差异明显,易造成地层损失加剧、地表非对称性沉陷等问题。本文以济南厚冲积黏性土地层盾构曲线施工为研究对象,探究隧道埋深及曲率半径对地表变形的影响规律,基于Peck公式结合现场实测数据,建立曲线盾构施工地表沉降预测公式。研究结论:(1)曲线盾构掘进受转弯段刀盘超挖、主动铰接盾壳挤压土体、千斤顶不平衡推力等因素的影响,致使隧道两侧地层差异扰动、地表变形非对称性;(2)在1.5~3倍隧道直径的埋深范围内,地表峰值沉降、沉降槽宽度系数及地层损失率随埋深的增大呈线性递增,地表沉降槽偏移量随曲率半径的减小呈线性递增;(3)修正Peck公式与现场实测数据吻合较高,修正系数取值范围为α=0.46~0.52,β=0.43~1.16;(4)该研究成果对黏性土地层曲线盾构施工地表变形预测及灾害防控具有指导意义。
Research purposes： The engineering problems, such as violent ground deformation, asymmetrical surface subsidence, are easily to be caused by small - radius curved shield construction, and the surface deformation law in small- radius curved shield construction has obviously variation with shield driving in straight line. In the engineering background of small -radius curved shield construction in thick alluvial clay strata in Jinan, the influence law of tunnel depth and radius of curvature on surface deformation was discussed. The surface deformation prediction formula for curved shield tunnel was established based on the Peck formula and field monitoring data. Research conclusions： （ 1 ） The phenomenon of differential disturbance on both sides of tunnel and asymmetrical surface deformation was caused by the influence of cutterhead overbreaking in shield turning part, shield shell pushing stratum by actively - hinged and uneven thrust of hydraulic jack. （2） The maximum surface settlement, width coefficient of settlement trough and ground loss ratio increase linearly with the increase of buried depth in the buried depth of 1.5 ~ 3 times tunnel diameter. The surface subsidence trough migration increases linearly with the decrease of radius ofcurvature. （3） The modified Peck formula fits well with the field monitoring data, and is α = 0.46 - 0.52, β = 0.43 - 1.16. （4） The research results are of important guidin ground deformation and prevention and control of disaster for small radius curve shield the range of correction coefficie g significance to tunnel in clay s the prediction tratum. nt of
作者
路林海
孙捷城
周国锋
谭生永
刘浩
李罡
LU Lin - hai;SUN Jie - cheng;ZHOU Guo - feng;TAN Sheng - yong;LIU Hao;LI Gang(Jinan Rail Transit Group Co. Ltd, Jinan, Shandong 250101, China;Jinan Railway Bureau, Jinan, Shandong 250100, China)
出处
《铁道工程学报》
EI
北大核心
2018年第5期99-105,共7页
Journal of Railway Engineering Society
基金
山东省自然科学基金项目(ZR2017MEE065
ZR2014EEQ028)
住房城乡建设部科学技术项目(2016-K4-053)
山东省住建厅科学技术项目(2017-K2-011
2017-K2-012
2018-K5-02
FW-20161001:A7)
济南市社会民生重大专项(201704140)
济南市优秀创新团队(济政字[2016]40号)
济南市5150人才资助项目
关键词
曲线盾构施工
黏性土地层
地表变形规律
影响因素
Peck公式修正
curved shield construction
clay stratum
surface deformation laws
influencing factors
Peck formulamodification
