- 摘 要
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(江苏华岩建设有限公司, 苏州 215101)
摘要: 以周边环境要求高、地质条件复杂、非常规施工的某工程为例,详细分析其工程特点。 采用正交分析法对桩基及基坑进行统筹设计,以实测结果分析桩基及基坑在开挖过程中的相互影响。 结果表明:对下部有较好持力层的深厚新填土场地选用载体桩是合理的,填土厚度、均匀性对载体桩单桩承载力影响不大;先行施工的永久性挡墙锚杆、灌注桩可明显提高基坑的整体稳定性;深厚新填土中采用桩侧压密注浆对提高载体桩抗压效果不明显,但可显著提高水平承载力;基坑开挖前施工的锚杆最大位移及塑性位移均明显大于基坑开挖后施工的锚杆;深层水平位移沿填土深度逐步减小,并在下部黏土顶面附近趋近于零。
关键词: 桩基; 基坑; 统筹设计; 深厚填土; 载体桩; 单桩承载力
中图分类号:TU473 1 文献标志码:A 文章编号:1002⁃848X(2022)14⁃0131⁃05
DOI:10 19701 / j jzjg 20200921
Overall design of pile foundation and foundation pit of recent deep filling site under restricted conditions
YUAN Yuntao, LI Suchun, HAN Shuang, LU Ruiwu
(Jiangsu Huayan Construction Co. , Ltd. , Suzhou 215101, China)
Abstract: Taking a project with high requirements of surrounding environment, complex geological conditions andunconventional construction as an example, the engineering characteristics were analyzed in detail. Overall design of pilefoundation and foundation pit was carried out by orthogonal analysis method, and the interaction between pile foundationand foundation pit in the excavation process was analyzed based on the measured results. The results show that it isreasonable to select piles with ram⁃compacted for recent deep filling site with better bearing layer. The thickness anduniformity of filling site have little influence on the bearing capacity of piles with ram⁃compacted. The anchor rod inpermanent retaining wall and cast⁃in⁃place piles constructed in advance construction can significantly improve the overallstability of the foundation pit. The effect of pile side compaction grouting in recent deep filling site on improving thecompressive capacity of piles with ram⁃compacted were not obvious, but it can significantly improve the horizontal bearingcapacity. The maximum displacement and plastic displacement of anchor rod constructed before the excavation of thefoundation pit are significantly greater than that of the anchor rod constructed after the excavation of the foundation pit. Thedeep horizontal displacement decreases gradually along the filling soil depth and tends to zero near the top surface of thelower clay.
Keywords:pile foundation; foundation pit; overall design; deep filling soil; piles with ram⁃compacted; bearing capacity of single pile
∗苏州市建设系统科研项目(2020 年度)。第一作者:袁运涛,硕士,高级工程师,主要从事岩土及地下结构工程研究工作,Email:635102933@ qq. com。[引用本文] 袁运涛,李苏春,韩霜,等. 受限条件下深厚新填土场地桩基及基坑统筹设计[J]. 建筑结构,2022,52(14):131⁃135. YUAN Yuntao,LI Suchun,HAN Shuang,et al. Overall design of pile foundation and foundation pit ofrecent deep filling site under restricted conditions[J]. Building Structure,2022,52(14):131⁃135.