摘要
以洛阳龙门地铁车站狭长深基坑工程为依托,运用Midas-GTS/NX有限元软件并结合现场监测数据,研究了不同开挖阶段基坑长短边围护结构及土体沉降变形规律,并提出狭长深基坑变形控制措施。结果表明:对于狭长型深基坑在不同施工阶段,由于空间效应的影响,基坑长边范围内土体沉降及围护结构变形明显大于短边方向,且随着基坑开挖和钢支撑的架设,桩体变形由“悬臂式”逐渐转变为“鼓肚状”,两个方向最大水平位移最终稳定在0.62H~0.78H,最大值达到11.88 mm和8.21 mm。长边方向最大沉降距坑边约为15 m处,短边约为10 m处,两个方向最大沉降差值为3.36 mm。桩体弯矩与开挖深度成正比,长边方向最大弯矩值是短边的1.51倍。桩体水平位移对钢支撑的架设位置比较敏感,且随着桩体嵌固深度的增加变形明显减小,但超过一定嵌固深度,变形控制效果减弱。
Based on the long and narrow deep foundation pit project of Luoyang Longmen metro station, Midas GTS/NX finite element software combined with field monitoring data was used to study the laws of retaining structure of long and short sides of foundation pit and soil settlement and deformation at different excavation stages. The deformation control measures of narrow and long deep foundation pit were put forward. The results show that for long and narrow deep foundation pits at different construction stages, due to spatial effects, the soil settlement and the deformation of the retaining structure within the long side of the foundation pit are significantly greater than that of the short side. And with the erection of steel supports, the pile deformation gradually changes from cantilever to bulging. The maximum horizontal displacement in the two directions is finally stable between 0.62Hand 0.78H, and the maximum value reaches 11.88 mm and 8.21 mm. The maximum settlement in the long side is about 15 m from the pit edge, and the short side is about 10 m away.The maximum settlement difference between the two directions is 3. 36 mm. The bending moment of the pile is proportional to the excavation depth, and the maximum bending moment in the long side direction is 1. 51times that of the short side. The horizontal displacement of the pile body is sensitive to the erection position of the steel support, and the deformation decreases significantly with the increase of the depth of the pile body embedding, but the deformation control effect is weakened beyond a certain embedding depth.
作者
张俊杰
高林静
范兆东
郭伟轩
李文杰
ZHANG Junjie;GAO Linjing;FAN Zhaodong;GUO Weixuan;LI Wenjie(The City Construction Company Ltd.of China Railway 15th Bureau Group,Luoyang 471013,China;Civil Engineering School,Henan University of Science&Technology,Luoyang 471023,China;China Railway 19th Bureau Group Co.,Ltd.,Beijing 100176,China)
出处
《河南科技大学学报（自然科学版）》
CAS
北大核心
2022年第6期59-66,M0006,M0007,共10页
Journal of Henan University of Science And Technology:Natural Science
基金
国家自然科学基金项目(U1604135)
中铁十一局集团有限公司重点科研课题(18-AⅡ-02)
中铁十五局集团有限公司重点科研课题(2019C51)
中铁十九局集团有限公司重点科研课题(19-A04)。
关键词
地铁车站
狭长深基坑
沉降及变形规律
有限元分析
现场监测
控制措施
subway station
long and narrow deep foundation pit
settlement and deformation law
finite element analysis
on site monitoring
control measures
