基于下负荷面本构的盾构掘进响应计算  

Calculation of Shield Tunneling Response Based on Subloading Cam-Clay Model

作　　者：李亮 陆勇 范存新[1] 郭兵 李安勇[1] LI Liang;LU Yong;FAN Cunxin;GUO Bing;LI Anyong(School of Civil Engineering,Suzhou University of Science and Technology,215011,Suzhou,China;China Railway 16th Bureau Group Beijing Metro Engineering Construction Co.,Ltd.,100018,Beijing,China)

机构地区：[1]苏州科技大学土木工程学院,苏州215011 [2]中铁十六局集团北京轨道交通工程建设有限公司,北京100018

出　　处：《城市轨道交通研究》2024年第12期24-31,共8页Urban Mass Transit

基　　金：江苏省高等学校基础科学(自然科学)研究项目(22KJB170020);江苏省建设系统科技项目(2017ZD204);江苏省研究生科研创新计划项目(KYCX22_3284)。

摘　　要：[目的]盾构在富水软弱地层中施工时,地层变形往往会受土体强度、变形及渗透特性的共同影响,其中渗透特性导致的时间效应会进一步影响周围环境。因此,有必要采用合理的本构模型开展应力渗流耦合计算,研究饱和粉质黏土中盾构掘进诱发的地层变形响应。[方法]以苏州轨道交通11号线鱼池泾站—白河潭站区间为例,采用能够反映土体力学特性状态相关性的下负荷面本构模型,并结合应力渗流耦合有限元程序,计算分析饱和粉质黏土中盾构掘进引起的地面沉降及孔隙水压力响应规律,并与工程实测数据进行对比。[结果及结论]基于下负荷面本构模型的应力渗流耦合计算能够较好地再现盾构掘进影响效应;饱和粉质黏土地层中的盾构掘进容易诱发地层变形,且掌子面压力的变化对地层变形有显著影响,掌子面压力过大往往会诱发地面隆起;盾构施工会对掘进面前方土体产生挤压扰动,继而诱发周围土层中超孔隙水压力演化,这也是地层变形时间效应的内在机制。[Objective]During shield tunneling in water-rich soft strata,ground deformation is often influenced by the combined effects of soil strength,deformation,and permeability characteristics.The time effect caused by permeability characteristics may further impact the surrounding environment.Therefore,it is necessary to use a reasonable constitutive model to conduct stress-seepage coupling calculations,and study the ground deformation response induced by shield tunneling in saturated silty clay.[Method]Taking the Yuchijing Station-Baihetan Station interval on Suzhou Rail Transit Line 11 as an example,a subloading Cam-Clay model that reflects the state correlation of soil mechanical properties is adopted,and combined with a stress-seepage coupling finite element program,to calculate and analyze the land subsidence and pore water pressure response patterns induced by shield tunneling in saturated silty clay.The results are compared with the field-measured engineering data.[Result&Conclusion]The stress-seepage coupling calculation based on the subloading Cam-Clay model can effectively reproduce the effects of shield tunneling.Shield tunneling in saturated silty clay can easily induce ground deformation,which is significantly affected by changes in the excavation face pressure.The excessive excavation face pressure often induces ground heave.Shield construction causes extrusion disturbance to the soil in front of the excavation face,which in turn induces the evolution of excess pore water pressure in the surrounding soil layers.This is also the intrinsic mechanism for the time effect of ground deformation.

关 键 词：隧道 盾构掘进响应 下负荷面本构模型 应力渗流耦合计算 

分 类 号：U455.43[建筑科学—桥梁与隧道工程]