摘要
为研究大直径盾构切穿护岸抗滑桩对堤岸的扰动影响,确保盾构隧道穿越过程中大堤的安全性与稳定性,采用有限元分析软件建立了隧道-桩基-堤岸三维数值模型,重点分析了盾构切穿施工时堤岸及桩体的变形规律,并对比了不同盾构推力下桩体的变形差异.研究结果表明:盾构切削护岸抗滑桩将导致大堤迎水面边坡产生较大扰动,坡顶出现最大纵向位移,被切桩周围土体出现明显下沉;在盾构推力以及迎水面滑坡推力的双重影响下,抗滑桩以挠曲变形为主,整体形成一条倾斜的“S”形曲线,盾构刀盘抵近桩体时的抗滑桩挠曲变形最为明显;盾构推力由0.7倍静止土压力增至0.9倍,桩身水平位移大幅增加,盾构刀盘抵近桩基时的桩底位移增幅高达162%.综上可知,盾构切削穿越抗滑桩时应严格控制推进速度、泥水压力等施工参数,以减小盾构推力对堤岸及桩体的不利影响.
This study analyzed the disturbance effect on embankment of large-diameter shield cutting through the anti-slide piles,with the goal of ensuring the safety and stability of the levee during the process of shield tunneling.A three-dimensional numerical model of tunnel-pile foundation-embankment was established using finite element analysis software.The settlement of the levee and the deformations of piles during shield tunneling were analyzed,and the deformations of piles under different shield thrust were compared.Results showed that the cutting of anti-slide piles by shield machine caused great disturbance to the upstream slope of the levee.The largest longitudinal displacement occurred at the top of the slope,and the soil around the piles showed obvious settlement.Under the influence of the shield thrust and landslide thrust,the anti-slide piles were characterized by flexure deformation,which formed a slanting“S”curve.The deflection of the antislide piles were the most obvious when the cutter head of the shield machine was close to it.The thrust of the shield increased from 0.7 to 0.9 times the static earth pressure.The horizontal displacement of the pile significantly increased.The displacement of the pile bottom increased by 162% when the cutter head approached the pile foundation.Therefore,when a shield machine cut through anti-slide pile,the construction parameters such as the advancing speed and mud-water pressure should be strictly controlled to reduce the adverse effect of shield thrust on the pile.
作者
蒋啸天
李章林
何国军
张孟喜
赵慧玲
JIANG Xiaotian;LI Zhanglin;HE Guojun;ZHANG Mengxi;ZHAO Huiling(School of Mechanics and Engineering Science,Shanghai University,Shanghai 200444,China;Shanghai Tunnel Engineering Co.,Ltd.,Shanghai 200032,China)
出处
《上海大学学报（自然科学版）》
CAS
CSCD
北大核心
2024年第1期164-173,共10页
Journal of Shanghai University:Natural Science Edition
基金
国家自然科学基金资助项目(52078286)
上海隧道工程有限公司重大项目科研课题资助项目(2020-SK-13)。
关键词
盾构隧道
堤岸变形
抗滑桩
切削桩基
shield tunnel
embankment deformation
anti-slide pile
pile cutting
作者简介
通信作者:张孟喜(1963-),男,教授,博士生导师,博士,研究方向为隧道及地下结构、新型土工加筋技术等.E-mail:mxzhang@i.shu.edu.cn。
