基础埋深对碎石桩复合地基桩体破坏模式的影响
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TU441

基金项目:

国家重点研发计划(2017YFC0805407);国家自然科学基金重点项目(41630641);国家自然科学基金青年项目(51708405);天津市科技计划项目(16YDLJSF00040)。


Influence of composite foundation embedded depth on the failure modes of stone columns
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    摘要:

    针对碎石桩复合地基中桩体性能,通过有限差分数值模拟与模型试验对比分析,验证了数值模型的可靠性,进而通过变化饱和黏土中碎石桩复合地基的埋置深度,分析了复合基础下单桩与群桩的承载特性和破坏模式。研究结果表明:增加复合地基的基础埋深,单桩复合地基的基础外土体围压增强,桩体侧向约束增加,桩体的最大径向位移减小,桩体破坏位置沿桩体向下移动;群桩复合地基桩体的破坏模式主要由桩体所在位置决定,中心桩破坏位置位于桩体较深处,边桩的破坏位置发生在桩顶附近,基础埋深对边桩的侧向约束作用较明显;摩擦型群桩复合地基破坏模式随埋置深度发生转变,并导致桩体破坏模式由最初沿水平方向鼓胀(剪切)破坏转变成为向下的刺入破坏。

    Abstract:

    Performance of stone columns in composite foundation was investigated through finite difference method(FDM) that was verified by published experimental results of model tests, and then the effect of embedded depth of composite foundation on failure mode of single column and group columns in saturated clay soil was analyzed. The research results show that with the increase of the embedded depth of composite foundation, the surrounding pressure of the single column increases, the lateral constrains function is enhanced, the horizontal maximum deformation along stone columns reduces, and the failure location move down gradually along stone column. In the cases of a group of stone columns, the failure mode of columns is determined by the location of columns under composite foundation. Compared with side stone columns whose failure location is near to the top of the columns, the failure of the central column is located in the deeper parts of the columns. The lateral restraint effect of the foundation embedded depth on the side column is obvious. The failure mechanism of the friction columns transforms from the initial bulging(shearing)along the horizonal direction to downward penetration when the embedment depth becomes large.

    参考文献
    [1] 郑刚, 龚晓南, 谢永利, 等. 地基处理技术发展综述[J]. 土木工程学报, 2012, 45(2):127-146.ZHENG Gang, GONG Xiaonan, XIE Yongli, et al. State-of-the-art techniques for ground improvement in China[J]. China Civil Engineering Journal, 2012, 45(2):127-146. (in Chinese)
    [2] Hughes J M O, Withers N J. Reinforcing of soft cohesive soils with stone columns[J]. International Journal of Rock Mechanics and Mining Sciences & Geomechanics Abstracts, 1974, 11(11):A234.
    [3] Hughes J M O, Withers N J, Greenwood D A. A field trial of the reinforcing effect of a stone column in soil[J]. Géotechnique, 1975, 25(1):31-44.
    [4] Bae W S, Shin B W, An B C, et al. Behaviors of Foundation System Improved With Stone Columns[J]. 한국마린엔지니어링학회2012년도후기학술대회논문집, 2002.
    [5] Madhav M R, Vitkar P P. Strip footing on weak clay stabilized with a granular trench or pile[J]. Canadian Geotechnical Journal, 1978, 15(4):605-609.
    [6] Muir Wood D, Hu W, Nash D F T. Group effects in stone column foundations:model tests[J]. Géotechnique, 2000, 50(6):689-698.
    [7] Aboshi H, Ichimoto E, Harada K, et al. The composer-A method to improve the characteristics of soft clays by inclusion of large diameter sand columns[C]//Proceedings of International Conference on Soil Reinforcement. Paris, ENPC-LCPC 1979:211-216.
    [8] Zhou H Z, Diao Y, Zheng G, et al. Failure modes and bearing capacity of strip footings on soft ground reinforced by floating stone columns[J]. Acta Geotechnica, 2017, 12(5):1089-1103.
    [9] 郑刚, 周海祚, 刁钰, 等. 饱和黏性土中散体桩复合地基极限承载力系数研究[J]. 岩土工程学报, 2015, 37(3):385-399.ZHENG Gang, ZHOU Haizuo, DIAO Yu, et al. Bearing capacity factor for granular column-reinforced composite ground in saturated soft clay[J]. Chinese Journal of Geotechnical Engineering, 2015, 37(3):385-399. (in Chinese)
    [10] Grzyb-Faddoul A M. Numerical analysis of the reinforcement of existing foundations by the Soil Mixing technique[J]. Ph. D. dissertation, L'Institut National des Sciences Appliquées de Lyon.
    [11] 邓楚键, 孔位学, 郑颖人, 等. 极限分析有限元法讲座Ⅲ:增量加载有限元法求解地基极限承载力[J]. 岩土力学, 2005, 26(3):500-504.DENG Chujian, KONG Weixue, ZHENG Yingren, et al. Analysis of ultimate bearing capacity of foundations by elastoplastic FEM through step loading[J]. Rock and Soil Mechanics, 2005, 26(3):500-504. (in Chinese)
    [12] 魏芸, 闫澍旺. 碎石墩复合地基的承载机理及破坏过程[J]. 土木工程学报, 2011, 44(7):111-118.WEI Yun, YAN Shuwang. Bearing mechanism and destruction process of stone column composite foundations[J]. China Civil Engineering Journal, 2011, 44(7):111-118. (in Chinese)
    [13] Park Y M, Shin E C, Ahn S R. Geotechnical properties of soft marine clay in Korea[C]//The Sixth International Offshore and Polar Engineering Conference. International Society of Offshore and Polar Engineers, 1996.
    [14] Berezantsev V C, Khristoforov V, Golubkov V. Load-bearing capacity and deformation of piled foundations[C]//International Conference on Soil Mechanics and Foundation Engineering, 1961.
    [15] 盛崇文. 软土地基用碎石桩加固后的极限承载力计算[J]. 水利水运科学研究, 1980(2):3-11.SHENG Chongwen. Calculation of ultimate bearing capacity of soft soil foundation with gravel piles[J]. Journal of Hydraulic Engineering, 1980(2):3-11. (in Chinese)
    [16] Ambily A P, Gandhi S R. Behavior of stone columns based on experimental and FEM analysis[J]. Journal of Geotechnical and Geoenvironmental Engineering, 2007, 133(4):405-415.
    [17] Zhou H Z, Zheng G, Yu X X, et al. Bearing capacity and failure mechanism of ground improved by deep mixed columns[J]. Journal of Zhejiang University-Science A, 2018, 19(4):266-276.
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肖成志,夏博洋,郑刚,刘志,周海祚.基础埋深对碎石桩复合地基桩体破坏模式的影响[J].重庆大学学报,2019,42(7):63-69.

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  • 收稿日期:2018-12-30
  • 在线发布日期: 2019-07-27
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