Displacement changes of the soil around the squeezed branch pile directly affect its vertical bearing capacity,while,traditional test methods are different to obtain the deformation characteristics of soil around the pile. The transparent soil model test was carried out,which is based on transparent materials and particle image velocimetry(referred to as PIV) technique,and the soil displacement around the branch pile and soil around equal section pile under axial load are tested by non-intrusive measurement. Test results show:compared with the equal section pile,squeezed branch pile can increase the bearing capacity by increasing the scope of the soil deformation displacement field and inducing the strength of the soil deformation displacement field. The soil displacement around the branches and that under the pile tip both have radial features,which shows the branch and the pile tip have the same bearing capacity,and the branches share a part of the pile load and change load transfer law. According to the soil displacement field around the branch,the soil displacement under the branch has a negative effect on the lateral frictional resistance of the pile. The position and distance of the branches have a great influence on the soil displacement field of around the branch pile through the test,and the distance between the branches should better be more than three times of the branch diameter.
张敏霞,崔文杰,徐 平,牛月君. 竖向荷载作用下挤扩支盘桩桩周土体位移场变化规律研究[J]. 岩石力学与工程学报, 2017, 36(S1): 3569-3577.
ZHANG Minxia,CUI Wenjie,XU Ping,NIU Yuejun. Research on soil displacement field around the squeezed branch pile under vertical load. , 2017, 36(S1): 3569-3577.
钱德玲. 挤扩支盘桩受力性状的研究[J]. 岩石力学与工程学报, 2003,22(3):494-499.(QIAN Deling. Study on bearing behavior of squeezed branch pile[J]. Chinese Journal of Rock Mechanics and Engineering,2003,22(3):494-499.(in Chinese))
[2]
王东坡,钱德玲. 挤扩支盘桩的荷载传递规律及研究现状[J]. 岩石力学与工程学报,2004,23(增1):4 645-4 648.(WANG Dongpo,QIAN Deling. Law of load transmission of squeezed branch piles and it’s research advances[J]. Chinese Journal of Rock Mechanics and Engineering,2004,23(Supp.1):4 645-4 648.(in Chinese))
[3]
巨玉文,梁仁旺,赵明伟. 挤扩支盘桩承载变形特性的试验研究[J]. 建筑技术,2003,34(3):178-180.(JU Yuwen,LIANG Renwang,ZHAO Mingwei. Experimental study on bearing deformation property of squeezed branch pile[J].Architecture Technology,2003,34(3):178-180.(in Chinese))
[4]
巨玉文,梁仁旺,赵明伟. 挤扩支盘桩的荷载传递法及数值模拟[J]. 建筑技术,2004,35(3):204-205.(JU Yuwen,LIANG Renwang,ZHAO Mingwei. Load transmission method of squeezed branch pile and its numerical simulation[J]. Architecture Technology,2004,35(3):204-205.(in Chinese))
[5]
GAO X J,WANG J C,ZHU X R. Static load test and load transfer mechanism study of squeezed branch and plate pile in collapsible loess foundation[J]. Journal of Zhejiang University:Science A,2007,8(7):1 110-1 117.
[6]
杨俊杰,章雪峰,彭孔曙. 挤扩支盘桩桩土相互作用的模型试验研究[J]. 工业建筑,2005,35(增1):447-451.(YANG Junjie,ZHANG Xuefeng,PENG Kongshu. Experimental research on the interaction between piles with branches and plates and surrounding soil[J]. Industrial Construction,2005,35(Supp.1):447-451.(in Chinese))
[7]
王树仁,李启民,武崇福,等. 荷载作用下挤扩支盘桩支护特性数值模拟分析[J]. 岩土力学,2007, 28(增1):658-662.(WANG Shuren,LI Qimin,WU Chongfu,et al. Numerical analysis of the squeezed branch piles under loading for protecting foundation excavation[J]. Rock and Soil Mechanics,2007,28(Supp.1):658-662.(in Chinese))
[8]
王伊丽,徐良英,李碧青,等. 挤扩支盘桩竖向承载力特性和影响因素的数值研究[J]. 土木工程学报,2015,48(增2):158-162. (WANG Yili,XU Liangying,LI Biqing,et al. Finite element numerical study on the axial bearing behaviors and factors of squeezed branch pile[J]. China Civil Engineering Journal,2015,48(Supp.2):158-162.(in Chinese))
ISKANDER M,SADEK S,LIU J Y. Optical measurement of deformation using transparent silica gel to model sand[J]. International Journal of Physical Modelling in Geotechnics,2002,2(4):13-26.
[11]
LEHANE B M,GILL D R. Displacement fields induced by penetrometer installation in an artificial soil[J]. International Journal of Physical Modelling in Geotechnics,2004,4(1):25-36.
[12]
NI Q,HIRD C C,GUYMER I. Physical modelling of pile penetration in clay using transparent soil and particle image velocimetry[J]. Geotechnique,2010,60(2):121-132.
[13]
曹兆虎,孔纲强,刘汉龙,等. 基于透明土的管桩贯入特性模型试验研究[J]. 岩土工程学报,2014,36(8):1 564-1 568.(CAO Zhaohu,KONG Gangqiang,LIU Hanlong,et al. Model test on pipe pile penetration by using transparent soils[J]. Chinese Journal of Geotechnical Engineering,2014,36(8):1 564-1 568.(in Chinese))
[14]
曹兆虎,孔纲强,周 航,等. 基于透明土的静压楔形桩沉桩效应模型试验研究[J]. 岩土力学,2015,36(5):1 363-1 367.(CAO Zhaohu,KONG Gangqiang,ZHOU Hang,et al. Model test on installation effect of tapered piles in transparent soils[J]. Rock and Soil Mechanics,2015,36(5):1 363-1 367.(in Chinese))
[15]
齐昌广,陈永辉,王新泉,等. 细长桩屈曲的透明土物理模型试验研究[J]. 岩石力学与工程学报,2015,34(4):838-848.(QI Changguang,CHEN Yonghui,WANG Xinquan,et al. Physical modeling experiment on buckling of slender piles in transparent soil[J]. Chinese Journal of Rock Mechanics and Engineering,2015,34(4):838-848.(in Chinese))