近接既有结构深大基坑隆起变形控制——以天津地铁5号线思源道站接建地下空间工程为例  

Heave Deformation Control Method of Large-scale Deep Foundation Pit Adjacent to Existing Structure:Taking the Underground Space Project Connecting to Siyuandao Station of Tianjin Metro Line 5 as an Example

作　　者：赵伟 陈桥枫 张富国[1] 李铁锋 李梅丽 刘世玉 许杰[1] ZHAO Wei;CHEN Qiao-feng;ZHANG Fu-guo;LI Tie-feng;LI Mei-li;LIU Shi-yu;XU Jie(China Railway 18th Bureau Group Co.,Ltd.,Tianjin 300222,China;Key Laboratory Transportation Tunnel Engineering,Ministry of Education,Southwest Jiaotong University,Chengdu 610031,China)

机构地区：[1]中铁十八局集团有限公司,天津300222 [2]西南交通大学交通隧道工程教育部重点实验室,成都610031

出　　处：《科学技术与工程》2023年第3期1192-1198,共7页Science Technology and Engineering

基　　金：国家重点研发计划(2018YFC0808700);非饱和土力学特性及工程技术四川省高校工程研究中心开放基金(SC-FBHT2022-05)。

摘　　要：现行基坑支护规范抗隆起主要验算支护结构的稳定,无法满足拓建工程对基坑隆起变形的严格要求。从力学平衡和刚度控制的角度,阐明了深大基坑隆起的力学机理和隆起荷载的计算方法,提出了控制基坑隆起的新途径。研究表明:基坑隆起荷载与支护结构的入土深度、基坑深度、基坑宽度、土体内摩擦角和土体重度等因素有关;将基坑隆起问题转化为坑底加固土层的平衡问题,可以作为拓建工程基坑隆起控制的计算方法;坑底土体刚性加固和抗拔桩是控制基坑隆起变形的重要措施,坑底加固和抗拔桩应在基坑开挖前实施。Anti uplift in the current foundation pit support code is mainly used to check the stability of the support structure,which cannot meet the strict requirements of the extension project on the upheaval deformation of the foundation pit.From the point of view of mechanical balance and stiffness control,the mechanical mechanism of deep and large foundation pit heave and the calculation method of uplift load were expounded,and a new way was put forward to control the uplift of foundation pit.The results show that the uplift load of foundation pit is related to soil penetration depth of supporting structure,depth and width of foundation pit,the internal friction angle and the weight of soil mass.The method of load balance of soil layer,which transforms the deformation of pit bottom into structural balance problem,can be used as the calculation method of foundation pit uplift control in extension engineering.The rigid reinforcement and anti pulling pile of the soil at the bottom of the pit are put forward to control the uplift deformation of the foundation pit,but this method should be implemented before the excavation of the foundation pit.

关 键 词：拓建工程 深大基坑 隆起荷载 计算方法 

分 类 号：TU463[建筑科学—结构工程]