软土群桩原位足尺试验研究

戴国亮; 戴永兴; 茅燕兵; 龚维明; 李小娟

doi:10.11779/CJGE2015S2031

软土群桩原位足尺试验研究 English Version

戴国亮^{1, 2},
戴永兴³,
茅燕兵³,
龚维明^{1, 2},
李小娟^{1, 2}

1. 混凝土及预应力混凝土结构教育部重点实验室,江苏南京 210018; 2.东南大学土木工程学院,江苏南京 210018; 3. 广州地铁设计研究院有限公司,广东广州 510010

基金项目: “973”计划资助项目（2013CB036304）

详细信息

作者简介:
戴国亮(1975- ),湖南安化人,东南大学教授,科研方向：桩基础及深基础。

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出版历程
- 收稿日期: 2015-03-25
- 发布日期: 2015-07-24

Full scale in-situ static loading tests on pile groups in soft soils

1. Key Laboratory for RC and PC Structures of Ministry of Education, Nanjing 210018, China; 2. School of Civil Engineering, Southeast University, Nanjing 210018, China; 3.Design Institute of Guangzhou Metro Corporation, Guangzhou 510010, China

摘要

摘要: 软土地区群桩基础受力机理复杂,目前阶段国内外关于群桩的现场足尺试验比较缺乏。在南京市江宁区软土地基进行了9桩的钻孔灌注群桩的足尺试验,试验桩桩径为400 mm,桩长分为20,24 m。通过布设在桩身各控制断面主筋上的钢筋计测量桩身轴力,在群桩中不同基桩桩顶的压力盒测量桩顶荷载。对比分析了单桩和群桩的沉降特性、轴力特性、侧摩阻力特性以及群桩中各基桩的荷载分配规律,并将实测的桩顶反力和群桩效应系数与理论方法计算所得结果进行了比较,结果表明弹性理论计算所得的群桩中各基桩桩顶荷载差异比实测值大;考虑应力叠加的群桩效应系数的公式以及Converse-Labrre群桩效应公式与本次试验的实测数据比较吻合。
- 群桩基础 /
- 足尺试验 /
- 现场试验 /
- 侧摩阻力 /
- 荷载分配 /
- 群桩效应系数
Abstract: The bearing characteristics of pile groups in soft soils are complex. At present there are few full scale tests on in-situ pile groups at domestic and abroad. Full scale tests on bored pile groups are conducted to explore the performance of pile groups in soft soils in Jiangning District of Nanjing City. The pile diameter is 400 mm, and the pile length is 20 and 24 m. The loading tests are carried out on a single pile and pile groups with nine piles. Steel bar meters are fixed in the piles to measure the axial force. Pressure cells are placed at the top of the piles to get the accurate load on them. The data of the tests are listed to show the comparison of settlement, axial force, side resistance and load distribution of the single pile and pile groups. The measured values of counterforce of pile head and the effect coefficient of pile groups are compared with those calculated by different kinds of theoretical methods. The results show that the load distribution calculated by the elastic theory in the pile groups has larger difference compared with the measured value. The results of the formula for pile group effect coefficient considering stress superposition and the Converse-Labrre's formula for pile group effect coefficient agree well with the measured values.
- pile group /
- full scale test /
- in-situ test /
- side resistance /
- load distribution /
- effect coefficient of pile group

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参考文献(9)

[1]	韩煊, 张乃瑞, 钟和, 等. 大型群桩基础静荷载试验与测试中的关键问题[J]. 工程勘察, 2005(1): 10-14. (HAN Xuan, ZHANG Nai-rui, ZHONG he, et al. Full scale static load test of pile foundation and the key problem in the test[J]. Geotechnical Investigation &Surveying, 2005(1): 10-14. (in Chinese))
[2]	BAI Xiao-hong, HE Wu-bin, JIA Jun-gang, et al. Experimental study on the interaction mechanism of cap-pile group-soil[J]. Marine Georesources and Geotechnology, 2006, 24(3): 173-182.
[3]	O'NEILL M W, HAWKINS R A, AUDIBERT J M E. Installation of pile group in overconsolidated clay[J]. Journal of the Geotechnical Engineering Division, ASCE, 1982, 108(11): 1369-1386.
[4]	PHUNG L D. Footings with settlement-reducing piles in non-cohesive soil[D]. Department of Geotechnical Engineering, Chalmers University of Technology, 1993.
[5]	刘金砺, 袁振隆. 粉土中桩孔群桩承台-桩-土相互作用特性和承载力计算[J]. 岩土工程学报, 1987, 9(6): 1-15. (LIU Jin-li, YUAN Zhen-long. Cap-pile-soil interaction of bored pile groups in silt and calculation on bearing capacity[J]. Chinese Journal of Geotechnical Engineering, 1987, 9(6): 1-15. (in Chinese))
[6]	Rodrigo Salgado. The engineering of foundation[M]. Newyork: Book-mart Press, 2005.
[7]	POULOS H G, DAVIS E H. Pile foundation analysis and design[M]. Newyork: John Wiley and Sons, 1980.
[8]	史佩栋. 实用桩基工程手册[M]. 北京: 中国建筑工业出版社, 1999: 114-121. (SHI Pei-dong. Practical pile foundation engineering manual[M]. Beijing: China Building Industry Press, 1999: 114-121. (in Chinese))
[9]	JTJ 254—98港口工程桩基规范[S]. 北京: 人民交通出版社, 1998. (JTJ 254—98 Port engineering pile specification[S]. Beijing: People's Communications Press, 1998. (in Chinese))