沉管基槽开挖诱发临岸结构变形数值模拟与实测分析  

Numerical simulation and field measurement analysis of coastal structures under immersed tunnel trench excavation

作　　者：刘力英 欧振锋 杨春山 段尚磊 LIU Liying;OU Zhenfeng;YANG Chunshan;DUAN Shanglei(Guangzhou Municipal Engineering Design&Research Institute Co.,Ltd.,Guangzhou 510060,Guangdong,China)

机构地区：[1]广州市市政工程设计研究总院有限公司,广东广州510060

出　　处：《隧道与地下工程灾害防治》2024年第4期12-19,共8页Hazard Control in Tunnelling and Underground Engineering

基　　金：广东省住房和城乡建设厅科技创新计划资助项目(2022-K4-094918)

摘　　要：为揭示沉管基槽开挖卸荷作用下临岸结构变形特征,以广州如意坊放射线系统工程为背景,通过建立三维数值模型及进行现场监测对基槽开挖过程中临岸厂房与加强护岸变形规律展开分析。研究结果表明:基槽边坡坡面土体整体往基槽方向移动,沿基槽方向最大位移为23.65 mm,出现在边坡中间部位变坡点处;基槽开挖诱发厂房整体往河床方向倾斜,厂房位移随基槽开挖深度增加而增大并最终趋于稳定,数值结果与实测结果一致,实测厂房最大沉降为5.66 mm,数值计算厂房垂直堤岸方向最大位移为8.13 mm,相邻柱基间沉降差与柱距之比最大值为0.264‰,满足规范限值要求,厂房运营安全;加强护岸变形以垂直堤岸方向为主,呈两端小中间大分布,最大为7.98 mm;坡顶设置钢板桩和基础注浆均可有效降低厂房结构变形,其中沉降降低效果显著,相比于未采取措施,同时设置钢板桩和注浆加固可降低厂房结构沉降约25%。In order to reveal the deformation characteristics of the adjacent structures induced by immersed tunnel trench excavation,the Ruyifang Radioactive System Project in Guangzhou was taken as the background to analyze the deforma⁃tion law of the adjacent plant buildings and the reinforced revetment during the foundation excavation by 3D⁃dimensional simulation and field measurement.The research results showed that the soil on the slope surface of the foundation trench moved as a whole towards the direction of the foundation trench,with a maximum displacement of 23.65 mm along the direction of the foundation trench,occurring at the point of slope change in the middle of the slope;The excavation of the foundation trench induces the overall tilting of the factory building towards the riverbed,and the displacement of the factory building increased with the depth of the foundation trench excavation and eventually stabilized,the numerical re⁃sults were consistent with the measured results,the maximum measured settlement of the factory building was 5.66 mm,and the maximum vertical displacement of the factory building in the direction of the embankment calculated numerically was 8.13 mm,the maximum ratio of the settlement difference between adjacent column foundations to the column spac⁃ing was 0.264‰,which met the requirements of the standard limit and ensured the safe operation of the factory build⁃ing;The reinforced revetment deformed mainly in the vertical direction of the embankment with the variations of small at both ends and large in the middle and the maximum of 7.98 mm generating in the revetment top middle;The installa⁃tion of steel sheet piles and foundation grouting at the top of the slope could effectively reduce the deformation of the factory structure,with a significant reduction in settlement.Compared with no measures taken,the simultaneous instal⁃lation of steel sheet piles and grouting reinforcement could reduce the settlement of the factory structure by about 25%.

关 键 词：沉管隧道 基槽开挖 沉降监测 数值分析 变形控制措施 

分 类 号：TU433[建筑科学—岩土工程]