摘要
为研究矿坑回填深、基岩起伏大的复杂岩层中桩基施工工艺,明晰基坑施工过程中围护结构变形特性,依托泰禾龙池基坑项目,针对特殊地层情况,进行了现场钻孔灌注桩施工工艺的研究,并对基坑施工过程中的土体位移、地表沉降规律进行分析。研究结果表明:(1)在矿坑回填深、基岩起伏大的地层中,采用全回转全套筒施工工艺,并根据现场地质情况采取相应的工艺改进措施,能有效保证灌注桩的施工质量,更好地确保基坑开挖的安全;(2)边坡沉降、边坡水平位移、坑外土体沉降、桩体应力及坑外深层土体水平位移都随着时间的变化呈增大趋势,但变化速率都远小于控制值;(3)在复杂地层中开挖基坑,采用灌注桩排桩加放坡的支护方式,基坑变形的控制效果较好。
In order to study the construction technology of pile foundation in complex rock formation with deep backfill and large bedrock surface fluctuation,and to clarify the deformation characteristics of the retaining structure during the construction of the foundation pit,based on the Taihelongchi foundation pit project,this paper studied the construction technology of bored piles,and analyzes the soil displacements and surface settlements during the construction of the foundation pit.The research results show that:(1)In the stratum with deep pit backfill and large undulation of bedrock surface,the full rotary and full-sleeve construction process was adopted,and corresponding process improvement measures were taken according to the on-site geological conditions,which can effectively ensure the construction quality of the cast-in-place pile and ensure the safety of the foundation pit excavation.(2)The slope settlement,the horizontal displacement of the slope,the soil settlement outside the pit,the pile stress and horizontal displacement of deep soil outside the pit all increase with the excavation,but deformation rates are far less than the control value.(3)The effect of the retaining method of cast-in-place piles to control the foundation pit deformation is quite good.
作者
詹晓波
纪元刚
姚王晶
ZHAN Xiao-bo;JI Yuan-gang;YAO Wang-jing(Zhejiang Dadi Geological Survey and Design Co.,Ltd.,Hangzhou 310030,Zhejiang,China;China Merchants Shekou Industrial Zone Holdings Co.,Ltd.,Shenzhen 518067,Guangdong,China;Institute of Geotechnical Engineering,Zhejiang University of Technology,Hangzhou 310023,Zhejiang,China)
出处
《地基处理》
2023年第4期354-360,共7页
Journal of Ground Improvement
关键词
基坑
钻孔灌注桩
施工技术
地表沉降
结构变形
全回转
基坑监测
foundation pit
bored piles
construction method
ground settlement
structure deformation
full rotation
foundation pit monitoring
