强震作用下可液化海床沉管隧道上浮机理研究  

RESEARCH OF FAILURE UPLIFT OF IMMERSED TUNNEL UNDER STRONG SEISMIC LOADING

作　　者：王秋哲 韩瑞 白笑笑 蒋家卫 赵凯[1] 陈国兴[1] WANG Qiu-zhe;HAN Rui;BAI Xiao-xiao;JIANG Jia-wei;ZHAO Kai;CHEN Guo-xing(Institute of Geotechnical Engineering,Nanjing Tech University,Nanjing,Jiangsu 210000,China;School of Construction Engineering and Management,Jiangsu Vocational College of Bussiness,Nantong,Jiangsu 226000,China)

机构地区：[1]南京工业大学岩土工程研究所,江苏南京210000 [2]江苏商贸职业学院建筑工程与管理学院,江苏南通226000

出　　处：《工程力学》2025年第4期121-129,共9页Engineering Mechanics

基　　金：国家自然科学基金项目(52408540,52378347);南通市自然科学基金项目(JC2023026);江苏省高等学校基础科学(自然科学)研究面上项目(24KJD560002);江苏省研究生科研与实践创新计划项目(KYCX24_1580)。

摘　　要：沉管隧道埋置于海床浅表层,与陆域隧道所处环境存在较大差异,开展沉管隧道的地震稳定性研究具有重要的科学意义和工程应用价值。在Biot动力固结方程框架下,构造土体黏弹塑性应力-应变滞回曲线,引入实时耦合的剪切-体积应变增量模型,基于FLAC3D计算平台实现了砂土液化过程的有效应力方法,并验证了该方法的有效性。以渤海海域中的典型钻孔作为场地条件,对砂质海床沉管隧道的地震稳定性进行了数值模拟,研究了砂质海床中沉管隧道上浮机理。结果表明:沉管侧壁摩擦阻力的减小,底部浮力的增大以及周围海床的大变形共同引起了沉管隧道的上浮,输入地震动加速度时程曲线的非对称性会导致沉管隧道两侧的非对称响应现象,进而引发沉管隧道结构两侧竖向位移时程的分离。The immersed tunnel is buried in the shallow surface of seabed,which is quite different from the land tunnel.It is of great scientific significance and engineering application value to study the seismic stability of immersed tunnel.Within the framework of Biot's dynamic consolidation equations,a viscoelastic-plastic stressstrain hysteresis curve for soil was constructed,and a real-time coupled shear-volumetric strain increment model was introduced.Based on the FLAC3D computational platform,an effective stress method for the sand liquefaction process was implemented,and the validity of this method was verified.Taking a typical borehole in Bohai sea as site condition,the seismic stability of immersed tunnel in sandy seabed was numerically simulated,and the uplift mechanism of immersed tunnel in liquefied seabed was studied.The results show that the decrease of the friction resistance of the side wall,the increase of the buoyancy of the bottom and the large deformation of seabed together lead to the uplift of the immersed tunnel.The asymmetric acceleration of the input ground motion leads to the asymmetric response phenomenon on both sides of the tunnel,and then leads to the separation of vertical displacement time history on both sides.

关 键 词：可液化海床 沉管隧道 有效应力方法 地震反应 土-结构相互作用 

分 类 号：TU93[建筑科学—结构工程]