土岩复合地层超深圆形基坑内衬墙作用效果及优化  

Effect and Optimization of the Inner Lining Wall of the Ultra-Deep Circular Foundation Pit in the Soil-Rock Composite Stratum

作　　者：赵一行 詹刚毅[3] 石钰锋[1,2] 简庆华 Zhao Yixing;Zhan Gangyi;Shi Yufeng;Jian Qinghua(Jiangxi Provincial Key Laboratory of Geotechnical Engineering Infrastructure Safety and Control,East China Jiaotong University,Nanchang 330013,China;Jiangxi Underground Space Technology Development Engineering Research Center,Nanchang 330013,China;China Railway Shanghai Design Institute Group Co.,Ltd.,Shanghai 200070,China;China Metallurgical Geology First Bureau Construction Engineering Co.,Ltd.,Langfang 065201,Hebei,China)

机构地区：[1]华东交通大学江西省岩土工程基础设施安全与控制重点实验室,南昌330013 [2]江西省地下空间技术开发工程研究中心,南昌330013 [3]中铁上海设计院集团有限公司,上海200070 [4]中国冶金地质总局一局建设工程有限公司,河北廊坊065201

出　　处：《吉林大学学报（地球科学版）》2023年第2期526-540,共15页Journal of Jilin University：Earth Science Edition

基　　金：国家自然科学基金项目(42177162);江西省交通运输厅科技项目(2021Z0004)。

摘　　要：为选择合理的支护方案,满足复杂地层条件下基坑的安全稳定和高效施工,以佛山市某超深圆形基坑为研究背景,采用数值模拟及现场监测手段,对土岩复合地层内衬墙作用效果进行分析,并分别对内衬墙厚度、施工方法、内衬墙布置形式进行优化。研究表明:内衬墙对地连墙受力变形起有利作用;相比有内衬墙支护,无内衬墙支护时地连墙受力变形增加较多,但均未超过规范要求预警值,表明该复合地层内衬墙具有一定的优化空间;地连墙水平位移、地连墙环向应力、坑外地表沉降量最大值与内衬墙厚度呈负相关,内衬墙厚度减小至0.80~0.60 m之间时,地连墙水平位移及环向应力作用效果减弱,内衬墙厚度减小至0.60~0.40 m之间时,坑外地表沉降量作用效果有所减弱;在最优厚度基础上,采用顺逆结合的施工方法既可保障基坑安全稳定,又可提高施工便利性。提出了不连续内衬墙布置形式,即,在最优厚度基础上,采用受压区较小时隔两层施作一层、较大时隔一层施作一层的布置形式,既安全又经济合理。In order to choose a reasonable support scheme to meet the requirements of safety,stability and efficient construction of the foundation pit under complex stratum conditions,taking an ultra-deep circular foundation pit in Foshan City as the research background,numerical simulation and field monitoring methods are used to analyze the effect of soil-rock composite lining wall,and optimize the lining wall thickness,construction method and layout form respectively.The results show that the lining wall has a favorable effect on the deformation of the ground connecting wall.Compared with lined wall support,the stress and deformation of ground connecting wall increase more in the case of unlined wall support,but it does not exceed the warning value required by the engineering standard,indicating that the composite lining wall has a certain optimization space.The maximum of the horizontal displacement,circumferential stress and surface settlement outside the pit are negatively correlated with the thickness of the lining wall.When the thickness is between 0.80 and 0.60 m,the effect of the horizontal displacement and circumferential stress is weakened,and when the thickness is between 0.60 and 0.40 m,the effect of surface settlement outside the pit is weakened.On the basis of optimal thickness,the construction method of combination of forward and backward can not only ensure the safety and stability of foundation pit,but also improve the construction convenience.The discontinuous lining wall layout is put forward,that is,on the basis of the optimal thickness,it is safe,economical and reasonable to adopt the layout of two layers after a small compression zone and one layer after a large compression zone.

关 键 词：超深圆形基坑 数值模拟 内衬墙 受力变形 优化 

分 类 号：TU94[建筑科学—建筑技术科学]