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JOURNAL OF ZHEJIANG UNIVERSITY (ENGINEERING SCIENCE)
    
Release of residual stress in existing preformed pile due to further excavation beneath  pile raft
GOU Yao-bo1, YU Feng1, XIA Tang-dai2
1.School of Civil Engineering and Architecture, Zhejiang Sci-Tech University, Hangzhou 310018, China; 2. Research Center of Coastal and Urban Geotechnical Engineering, Zhejiang University, Hangzhou 310058, China
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Abstract  

This study aims to improve the understanding on the stress state and bearing behavior of existing pile subjected to excavation beneath the raft or cap of the pile. Concerning high-rise buildings supported by preformed piles, analysis was carried out to observe the change of post-installation residual stress locked in the piles due to such excavation. A proposal for residual stress calculation was proposed by using a simplified simulation model and the principle of energy conservation. The parameters for calculating the residual stress were determined based on the models for pile's shaft and base resistances and the model for soil heave subjected to excavation. The change of residual stress due to excavation was thus derived. The results indicate that excavation leads to the loss of shaft and base capacities of the piles, but the rate of reduction is smaller than that for the residual stress. The release degree of the residual stress is related to the distance between the calculated point and the excavation surface, i.e., farther distance corresponds to smaller degree of release. This finding is an indicator that the release of residual stress is closely associated with the relative pile-soil displacement.



Published: 26 December 2015
CLC:  TU 473.1  
Cite this article:

GOU Yao-bo, YU Feng, XIA Tang-dai. Release of residual stress in existing preformed pile due to further excavation beneath  pile raft. JOURNAL OF ZHEJIANG UNIVERSITY (ENGINEERING SCIENCE), 2015, 49(5): 969-974.

URL:

http://www.zjujournals.com/eng/10.3785/j.issn.1008-973X.2015.05.023     OR     http://www.zjujournals.com/eng/Y2015/V49/I5/969


增层开挖引起既有预制桩残余应力释放分析

为了更好地理解地下室增层开挖后既有工程桩的应力状态和承载性状,以采用预制桩基础的高层建筑为研究对象,分析增层开挖对既有预制桩施工残余应力的影响.从施工残余应力简化模型和能量法概念出发,提出桩残余应力的计算模型,再结合增层开挖前后桩侧摩阻力和桩端阻力的计算模型以及回弹量的计算方法,确定计算残余应力所需的模型参数,模拟出增层开挖前后桩身残余应力的变化情况.结果表明,增层开挖会造成桩侧摩阻力及桩端阻力的损失,并引起更高幅度的桩身残余应力释放.同时,桩残余应力的释放程度与计算点到开挖面的距离有关,距离越远释放幅度越小,这说明残余应力的释放与桩-土间的相对位移有关.

[1] 贾强, 应惠清, 张鑫. 锚杆静压桩技术在既有建筑物增设地下空间中的应用[J]. 岩土力学, 2009, 30(7): 2053-2057.
JIA Qiang, YING Hui-qing, ZHANG Xin. Construction of basement in existing buildings by static bolt-pile [J]. Rock and Soil Mechanics, 2009, 30(7): 2053-2057.
[2] 杜斌,刘祖德,聂向珍,等. 既有建筑物基础托换技术中的钢管纤维桩工法[J]. 岩土力学, 2007, 28(5): 1040-1044.
DU Bin, LIU Zu-de, NIE Xiang-zhen, et al. Steel fiber pile technology in underpinning project of existing building [J]. Rock and Soil Mechanics, 2007, 28(5): 1040-1044.
[3] 文颖文,胡明亮,韩顺有, 等. 既有建筑地下室增设中锚杆静压桩技术应用研究[J]. 岩土工程学报, 2013, 35(增刊2):224-229.
WEN Ying-wen, HU Ming-liang, HAN Shun-you, et al. Application of static bolt-pile technique to construction of basement of existing buildings [J].Chinese Journal of Geotechnical Engineering, 2013, 35(S2): 224-229.
[4] ZHENG Gang, PENG Si-yuan, CHARLES W W, et al. Excavation effects on pile behaviour and capacity [J]. Canadian Geotechnical Journal, 2012, 49(12): 1347-1356.
[5] 胡琦, 凌道盛, 陈云敏, 等. 深基坑开挖对坑内基桩受力特性的影响分析[J]. 岩土力学, 2008, 29(7): 1965-1970.
HU Qi, LING Dao-sheng, CHEN Yun-min, et al. Study of loading characters of pile foundation due to unloading of deep foundation pit excavation [J]. Rock and Soil Mechanics, 2008, 29(7): 1965-1970.
[6] 陈锦剑, 王建华, 范巍, 等. 抗拔桩在大面积深开挖过程中的受力特性分析[J]. 岩土工程学报, 2009, 31(3): 402-407.
CHEN Jin-jian, WANG Jian-hua, FAN WEI, et al. Behavior of up-lift pile foundation during large-scale deep excavation [J]. Chinese Journal of Geotechnical Engineering, 2009, 31(3): 402-407.
[7] 杨敏, 逯建栋. 深开挖基坑回弹引起的坑中桩受力与位移计算[J]. 同济大学学报, 2010, 38(12): 1730-1735.
YANG Min, LU Jian-dong. A calculation of behavior of underpinning pile subject to excavation of deep foundation pit [J]. Journal of Tongji University, 2010, 38(12): 1730-1735.
[8] 龚晓南, 伍程杰,俞峰,等. 既有地下室增层开挖引起的桩基侧摩阻力损失分析[J]. 岩土工程学报, 2013, 35(11): 1957-1964.
GONG Xiao-nan, WU Chen-jie, YU Feng, et al. Shaft resistence loss of piles due to excavation beneath existing basements [J]. Chinese Journal of Geotechnical Engineering, 2013, 35(11): 1957-1964.
[9] 伍程杰,龚晓南,俞峰,等.既有高层建筑地下增层开挖桩端阻力损失分析[J].浙江大学学报:工学版, 2014, 48(4): 671-678.
WU Cheng-jie, GONG Xiao-nan, YU Feng, et al. Pile base resistance loss for excavation beneath the existing high-rise building[J]. Journal of Zhejiang University :Engineering Science, 2014, 48(4): 671-678.
[10]HUNTER A H, DAVISSON M T. Measurement of pile load transfer [C]∥Proceedings of Symposium on Performance of Deep Foundations. San Francisco: ASTM Special Technical Publication. 1969: 106-117.
[11] VESIC A S. On the significance of residual loads for load response of piles [C]∥Proceedings of the 9th International Conference on Soil Mechanics and Foundation Engineering. Tokyo: The Japanese Society of Soil Mechanics and Foundation Engineering.1977:374-379.
[12] 俞峰, 谭国焕,杨峻,等. 静压桩残余应力的长期观测性状[J]. 岩土力学,2011, 32(8): 2318-2324.
YU Feng, THAM Leslie George, YANG Jun, et al. Observed long-term behavior of the residual stress in jacked pile [J]. Rock and Soil Mechanics, 2011, 32(8):2318-2324.
[13] 浙江城建建筑设计院. 浙江饭店翻扩建工程施工图[R].杭州: 浙江城建建筑设计院, 1996.
Zhejiang Urban Construction and architectural design institute. Design paper of Zhejiang hotel expansion project[R]. Hangzhou: Zhejiang Urban Construction and Architectural Design Institute, 1996.
[14] 杭州市勘察测绘院. 浙江饭店翻扩建工程地质勘察报告[R]. 杭州: 杭州市勘察测绘院, 1996.
Hangzhou Surveying and Mapping Institute. Geological survey report of zhejiang hotel expansion project[R]. Hangzhou: Hangzhou Surveying and Mapping Institute, 1996.
[15] 俞峰,谭国焕,杨峻,等. 粗粒土中预制桩的静压施工残余应力[J]. 岩土工程学报,2011, 33(10):1526-1536.
YU Feng, THAM Leslie George, YANG Jun, et al. Post-installation residual stresses in preformed piles jacked into granular soils [J]. Chinese Journal of Geotechnical Engineering, 2011, 33(10):1526-1536.
[16] 刘俊伟.静压开口混凝土管桩施工效应试验及理论研究[D].杭州:浙江大学,2012:149-169.
LIU Jun-wei. Experimental and theoretical studies on the construction effects for jacked open-ended concrete pipe piles [D]. Hangzhou: Zhejiang University, 2012:149-169.
[17] 刘俊伟,俞峰,张忠苗,等.基于能量守恒的预制桩施工残余应力模拟[J]岩土力学,2012,33(4):1227-1232.
LIU Jun-wei, YU Feng, ZHANG Zhong-miao, et al. Simulation of post-installation residual stress in preformed piles based on energy conservation [J]. Rock and Soil Mechanics, 2012,33(4):1227-1232.
[18] VESIC A S. A study of bearing capacity of deep foundations [R]. Atlanta: Georgia Institute of Technology, Engineering Experiment Station, 1967.
[19] 刘国彬,黄院雄,侯学渊. 基坑回弹的实用计算法[J]. 土木工程学报, 2000, 33(4): 61-67.
LIU Guo-bin, HUANG Yuan-xiong, HOU Xue-yuan. Practical method for calculating a heave of excavated foundation [J]. China Civil Engineering Journal, 2000, 33(4): 61-67.

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