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| MODEL TEST STUDY OF EFFECT OF INCLINATION ON BEARING BEHAVIORS OF PLASTIC TUBE CAST-IN-PLACE CONCRETE PILE |
(1. Department of Civil Engineering，Zhejiang University City College，Hangzhou，Zhejiang 310015，China；2. Geotechnical Research Institute，Hohai University，Nanjing，Jiangsu 210098，China；3. Key Laboratory of Ministry of Education for Geomechanics and Embankment Engineering，Hohai University，Nanjing，Jiangsu 210098，China；4. Zhejiang Province Best Way
Communications Technology Development Co.，Ltd.，Hangzhou，Zhejiang 310012，China) |
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Abstract The bearing behaviors of vertical pile and inclined piles with inclination angles of 5°，8°，10° and 15° are contrasted according to model test. Effects of inclination on the bearing capacity of single plastic tube cast-in-place concrete pile(TC pile for short)，pile-top settlement，pile shaft horizontal displacement，bending moment along pile shaft，skin friction and the ratio of tip resistance to load on pile top are analyzed. The model test results show that：(1) Effects of pile inclination on the bearing capacity and pile-top settlement are not apparent when the inclination angle of TC pile is less than 8°；but for the inclined piles with inclination angles of 10° and 15°，the reduction of bearing capacity of single pile is significant. (2) Horizontal displacement and bending moment of pile shaft mainly occur in the upper one third of pile length；and both go up with the increase of load and inclination angle. (3) Skin frictions of vertical pile and each inclined pile first increase and then decrease with the increase of pile depth；and the mean values of ultimate skin frictions increase slightly with the increase of inclination angle；and the bearing ratio of skin friction is large. (4) Tip resistance and the ratio of tip resistance to load on pile top go up with the increase of load and fall with the increase of inclination angle. The Origin software is applied to fit the curve between ultimate bearing capacity and inclination angle with Sigmoidal function. The formula is obtained to calculate the ultimate bearing capacity of inclined pile. Based on the field data，the range of correction factor is gained.
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Received: 17 December 2010
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| [1] 苏 杰. 塑料套管现浇混凝土桩新型地基处理方式的试验研究[硕士学位论文][D]. 南京：河海大学，2008.(SU Jie. In-situ test study on new foundation treatment technique of plastic tube cast-in-place concrete pile[M. S. Thesis][D]. Nanjing：Hohai University，2008.(in Chinese))
[2] 张开伟. 塑料套管现浇混凝土桩复合地基桩土应力比试验研究[硕士学位论文][D]. 南京：河海大学，2009.(ZHANG Kaiwei. In-situ test study on pile-soil stress ratio of composite-foundation of plastic tube cast-in-place concrete pile[M. S. Thesis][D]. Nanjing：Hohai University，2009.(in Chinese))
[3] 郝 忠. 塑料套管现浇混凝土桩单桩承载特性研究[硕士学位论文][D]. 南京：河海大学，2009.(HAO Zhong. Study on the bearing characteristics of single plastic tube cast-in-place concrete pile[M. S. Thesis][D]. Nanjing：Hohai University，2009.(in Chinese))
[4] 徐建平，周 健，许朝阳，等. 沉桩挤土效应的模型试验研究[J]. 岩土力学，2000，21(3)：235–238.(XU Jianping，ZHOU Jian，XU Chaoyang，et al. Model test research on pile driving effect of squeezing against soil[J]. Rock and Soil Mechanics，2000，21(3)：235–238.(in Chinese))
[5] 周 健，张 刚，曾庆有. 主动侧向受荷桩模型试验与颗粒流数值模拟研究[J]. 岩土工程学报，2007，29(5)：650–656.(ZHOU Jian，ZHANG Gang，ZENG Qingyou. Model tests and PFC2D numerical analysis of active laterally loaded piles[J]. Chinese Journal of Geotechnical Engineering，2007，29(5)：650–656.(in Chinese))
[6] 安永福. 塑料套管混凝土桩倾斜对竖向承载特性的影响研究[硕士学位论文][D]. 南京：河海大学，2010.(AN Yongfu. Study on bearing deformation behaviour of single oblique piles of plastic tube cast- in-place concrete pile under vertical load[M. S. Thesis][D]. Nanjing：Hohai University，2010.(in Chinese))
[7] GIANNAKOU A，GEROLYMOS N，GAZETAS G，et al. Seismic behavior of batter piles：elastic response[J]. Journal of Geotechnical and Geoenvironmental Engineering，2010，136(9)：1 187–1 199.
[8] GEROLYMOS N，GIANNAKOU A，ANASTASOPOULOS I，et al. Evidence of beneficial role of inclined piles：observations and summary of numerical analyses[J]. Bulletin of Earthquake Engineering，2008，6(4)：705–722.
[9] PADRON L A，AZNAREZ J J，MAESO O，et al. Dynamic stiffness of deep foundations with inclined piles[J]. Earthquake Engineering and Structural Dynamics，2010，39(12)：1 343–1 367.
[10] ESCOFFIER S，CHAZELAS J L，GAMIER J. Centrifuge modeling of raked piles[J]. Bulletin of Earthquake Engineering，2008，6(4)：689–704.
[11] ZHANG L M，MCVAY M C，HAN S J，et al. Effects of dead loads on the lateral response of battered pile group[J]. Canadian Geotechnical Journal，2002，39(3)：561–575.
[12] MEYERHOF G G，YALCIN A S. Behaviour of flexible batter piles under inclined loads in layered soil[J]. Canadian Geotechnical Journal，1993，30(2)：247–256.
[13] MEYERHOF G G. Behaviour of pile foundations under special loading conditions：1994 R. M. Hardy keynote address[J]. Canadian Geotechnical Journal，1995，32(2)：204–222.
[14] 郑 刚，王 丽. 竖向荷载作用下倾斜桩的荷载传递性状及承载力研究[J]. 岩土工程学报，2008，30(3)：323–330.(ZHENG Gang，WANG Li. Load transfer and bearing capacity of inclined pile under vertical load[J]. Chinese Journal of Geotechnical Engineering，2008，30(3)：323–330.(in Chinese))
[15] 孔纲强，杨 庆，郑鹏一，等. 考虑时间效应的斜桩基负摩阻力室内模型试验研究[J]. 岩土工程学报，2009，31(4)：617–621.(KONG Gangqiang，YANG Qing，ZHENG Pengyi，et al. Model tests on negative skin friction resistance for inclined pile foundation considering time effect[J]. Chinese Journal of Geotechnical Engineering，2009，31(4)：617–621.(in Chinese))
[16] 武 军. 深厚软土中斜桩桩土相互作用研究[硕士学位论文][D]. 成都：西南交通大学，2009.(WU Jun. Study on pile-soil-pile interaction effects of battered pile in deep soft soil[M. S. Thesis][D]. Chengdou：Southwest Jiaotong University，2009.(in Chinese))
[17] RAJASHREE S S，SITHARAM T G. Nonlinear finite-element modeling of batter piles under lateral load[J]. Journal of Geotechnical and Geoenvironmental Engineering，2001，127(7)：604–612.
[18] 云天铨，云 飞，张桂标. 刚性斜桩顶部受任意力的位移的线载荷积分方程法的分析[J]. 应用力学学报，1992，9(4)：114–123.(YUN Tianquan，YUN Fei，ZHANG Guibiao. Analysis of displacement of rigid sloping pile under arbitrary loads at top by line-loaded integral equation method[J]. Chinese Journal of Applied Mechanics，1992，9(4)：114–123.(in Chinese))
[19] 屠毓敏，魏汝龙. 曲桩竖向承载力的确定[J]. 土木工程学报，1999，32(4)：64–68.(TU Yumin，WEI Rulong. Determination of the vertical bearing capacity of bent piles[J]. China Civil Engineering Journal，1999，32(4)：64–68.(in Chinese))
[20] 中华人民共和国行业标准编写组. JGJ106—2003建筑基桩检测技术规范[S]. 北京：中国建筑工业出版社，2003.(The Professional Standards Compilation Group of People?s Republic of China. JGJ106—2003 Technical code for testing of building foundation piles[S]. Beijing：China Architecture and Building Press，2003.(in Chinese)) |
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2011, Vol. 30 
