双层非均质地基中单桩受扭弹塑性分析

邹新军; 赵灵杰; 徐洞斌; 赵明华

doi:10.11779/CJGE201605008

双层非均质地基中单桩受扭弹塑性分析 English Version

1. 湖南大学土木工程学院,湖南长沙 410082;
2. 建发房地产集团有限公司,福建厦门 361008

基金项目: 国家自然科学基金项目（51378197; 51578231）

详细信息

作者简介:
邹新军(1975- ),男,博士,副教授,主要从事桩基础及复合地基的理论与应用研究。E-mail: xjzouhd@hnu.edu.cn。

中图分类号: TU43
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出版历程
- 收稿日期: 2015-04-20
- 发布日期: 2016-05-24

Elastic-plastic torsional behavior of single pile in double-layered non-homogeneous subsoil

1. College of Civil Engineering, Hunan University, Changsha 410082, China;
2. C & D Realty Co., Ltd., Xiamen 361008, China

摘要

摘要: 为探讨双层非均质地基中单桩的受扭承载特性,基于单层土体剪切模量呈幂函数分布的假定,考虑桩-土接触面上极限摩阻力随深度非线性变化,建立出桩顶扭矩作用下的桩身扭转控制方程,进而导得桩顶及桩身的扭矩(T)与扭转角(Φ)等解答,并将其退化为单层非均质及双层均质地基后与已有成果进行了对比验证。同时,桩顶T-Φ曲线参数分析结果表明：增加桩体剪切模量G_p有利于控制桩顶扭转角;桩径r₀增加一倍,相同扭转角下桩顶能承受的扭矩值增大4~6倍;随地面处土体剪切模量μ₁和模量分布函数中非线性系数α₁,α₂的增加,桩身受扭性能得到显著改善。此外,桩顶扭转影响因子I_Φ的对比分析表明：桩身在ζL<0.2和ζL>5.0时分别表现为刚性桩和柔性桩,且后者传至桩底的扭矩极小而可忽略;当ζL>5且上下土层顶部剪切模量比μ₁/μ₂>1时,0.2倍桩长(L)范围内的上部土层对桩身受扭性能影响较大;当ζL>10且μ₁/μ₂<1时,桩身受扭能力主要源自0.4L的表层土。
- 桩基础 /
- 双层非均质地基 /
- 扭矩荷载 /
- 弹塑性分析
Abstract: To discuss the torsional behavior of a single pile in double-layered non-homogeneous subsoil, assuming the shear modulus of each single layer as the power function distribution and considering a nonlinear variation of the limit friction resistance along the pile-soil interface, the governing differential equation for the pile shaft under torque is established. Then, the internal forces (torque T) and deformations (torsion angle Φ) at the pile top and along the pile shaft are obtained respectively. By simplifying the solutions to single-layered non-homogeneous or double-layered homogeneous subsoil, good agreements are found between the calculated results and the available achievements. Besides, a parameter analysis of pile top T-Φ curve shows that increasing the shear modulus of pile shaft G_p helps to control the torsional angle at pile top. And a double value of pile radius r₀ will result in an increase of 4~6 times the torsional resistance at pile top. Similarly, the performance of torsional piles can be improved by greater values of the nonlinear coefficients α₁ and α₂ and the surface modulus μ₁. Besides, comparative analysis results of torsional influence factors at pile top I_Φ show that the pile shaft can be seen as a rigid body for ζL<0.2, while a value of ζL>5.0 will cause a flexible pile with the torque transferred to the pile tip small enough to be ignored. Moreover, for a combined value of ζL>5.0 and shear modulus ratio of upper to lower layers μ₁/μ₂>1.0, the main contribution to torque resistance comes from the 0.2L surface subsoil, while the 0.4L surface soil layer will determine the torsional behavior of pile shaft for ζL>10 and μ₁/μ₂<1.0.
- pile foundation /
- double-layered non-homogeneous subsoil /
- torsional load /
- elastic-plastic analysis

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参考文献(15)

[1]	STOLL U W. Torque shear test of cylindrical friction piles[J]. Civil Engineering, 1972, 42(4): 63-65.
[2]	POULOS H G. Torsional response of piles[J]. Journal of Geotechnical Engineering Division, ASCE, 1975, 101(10): 1019-1035.
[3]	RANDOLPH M F. Piles subjected to torsion[J]. Journal of Geotechnical Engineering Division, ASCE, 1981, 107(8): 1095-1111.
[4]	CHOW Y K. Torsional response of piles in non-homogeneous soil[J]. Journal of Geotechnical Engineering, ASCE, 1985, 111(7): 942-947.
[5]	GUO W D, RANDOLPH M F. Torsional piles in non-homogeneous media[J]. Computers and Geotechnics, 1996, 19(4): 265-287.
[6]	RAJAPAKSER K N D. A torsion load transfer problem for a class of non-homogeneous elastic solids[J]. International Journal of Solids Structures, 1988, 24(2): 139-151.
[7]	刘云云, 陈竹昌. 扭矩作用下嵌岩桩桩顶内力分布的模型试验[J]. 岩土力学, 2000, 21(2): 119-122. (LIU Yun-yun, CHEN Zhu-chang. Model simulation of internal load distribution in rock-socketed piles subject to torsion[J]. Rock and Soil Mechanics, 2000, 21(2): 119-122. (in Chinese))
[8]	陈胜立, 寿汉平. 传递矩阵法分析层状地基中桩的扭转变形[J]. 岩土力学, 2004, 25(增刊2): 178-186. (CHEN Sheng-li, SHOU Han-ping. Analysis of torsional response of a single pile embedded in layered soil with transfer matrix method[J]. Rock and Soil Mechanics, 2004, 25(S2): 178-186. (in Chinese))
[9]	陈胜立, 张利民. 层状地基中单桩的扭转变形分析[J]. 岩土工程学报, 2005, 27(5): 531-535. (CHEN Sheng-li, ZHANG Li-min. Torsional response of single pile embedded in layered ground[J]. Chinese Journal of Geotechnical Engineering, 2005, 27(5): 531-535. (in Chinese))
[10]	KONG L G, ZHANG L M. Centrifuge modeling of torsionally loaded pile groups[J]. Journal of Geotechnical and Geoenvironmental Engineering, ASCE, 2007, 133(11): 1374-1384.
[11]	ZHANG L Y. Nonlinear analysis of torsionally loaded piles in a two-layer soil profile[J]. International Journal of Geomechanics, 2010, 10(2): 65-73.
[12]	邹新军, 徐洞斌, 王亚雄. 成层地基中单桩受扭弹塑性分析[J]. 湖南大学学报(自然科学版), 2014, 41(9): 72-78. (ZOU Xin-jun, XU Dong-bin, WANG Ya-xiong. Elastic- plastic analysis of torsional single pile in layered subsoil[J]. Journal of Hunan University (Natural Sciences), 2014, 41(9): 72-78. (in Chinese))
[13]	BASACK S, SEN S. Numerical solution of single piles subjected to pure torsion[J]. Journal of Geotechnical and Geoenvironmental Engineering, ASCE, 2014, 140(1): 74-90.
[14]	杜秦文. 土体剪切模量随深度连续变化非均质地基解析研究[D]. 杭州: 浙江大学, 2005. (DU Qin-wen. Analytical study on non-homogeneous subgrade with continuous variation of Shear modulu svesrus depth[D]. Hangzhou: Zhejiang University, 2005. (in Chinese))
[15]	HACHE R A G, VALSANGKAR A J. Torsional resistance of single pile in layered soil[J]. Journal of Geotechnical Engineering, ASCE, 1988, 114(2): 216-220.

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双层非均质地基中单桩受扭弹塑性分析 English Version

作者简介: 邹新军(1975- ),男,博士,副教授,主要从事桩基础及复合地基的理论与应用研究。E-mail: xjzouhd@hnu.edu.cn。

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Elastic-plastic torsional behavior of single pile in double-layered non-homogeneous subsoil

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目录

作者简介:
邹新军(1975- ),男,博士,副教授,主要从事桩基础及复合地基的理论与应用研究。E-mail: xjzouhd@hnu.edu.cn。