Experimental Study of Bearing Behavior of Composite Foundation with Flexible Pile and Lateral Restraint at Long-term Load

Abstract

Abstract:

Abstract： In order to study the bearing behavior of composite foundation with flexible pile at longterm load, comparative experiments of composite foundation with rammed soilcement pile with or without lateral restraint at longterm load were conducted. Settlement marks were laid on the surface of composite foundation to measure the sedimentation of pile and soil, from which the variation law of the sedimentation of pile and soil with time could be obtained. By laying earth pressure cells on the surface and bottom of the foundation and building PVC tube with stain gauge in pile shaft to measure the stress value, the stress variation of pile top and soil top, the stress ratio of pile soil and pile shaft tress change with time were analyzed. The results of comparative tests show that at longterm load, the performance of composite foundation of rammed soil-cement pile with lateral constraint length piles is obviously better than that without lateral restraint, which can greatly shorten the time step in stable phase (approximately 64%) and reduce the settlement after construction (approximately 29% to 42%), and decrease the pilesoil stress ratio approximately 39%, hence adjust the distribution of axial force of pile shaft significantly. It can be acknowledged that when soft soil is treated with flexible pile, the settlement after construction can be effectively reduced and bearing capacity of subgrade can be improved if rigid long pile is set as lateral restraint.

Key words: long-term load, lateral restraint, rammed soilcement pile, composite foundation, model experiment

CLC Number:

TU 447

WU Youping1,ZHANG Keneng1,LIU Jie2,HE Jie2. Experimental Study of Bearing Behavior of Composite Foundation with Flexible Pile and Lateral Restraint at Long-term Load[J]. Journal of Shanghai Jiaotong University, 2014, 48(11): 1568-1573.

References

［1］Chai J C，Carter J P．Deformation analysis in soft ground improvement［J］. Geotechnical，Geological and Earthquake Engineering，2011，18: 173234．

［2］Lai Y P，Bergado D T，Lorenzo G A，et al．Fullscale reinforced embankment on deep jet mixing improved ground［J］．Ground Improvement，2006，10(04)：153164．

［3］张磊，魏安．软土处理技术的研究与新进展［J］．铁道勘测与设计，2005(2)：6466．

ZHANG Lei， WEI An． Research and new development of treatment technology of soft soil［J］． Railway Survey and Design，2005(2)：6466．

［4］朱明，范建华．浅谈软土地基处理方法及施工工艺［J］．西部探矿工程，2009(1)：2628．

ZHU Ming，FAN Jianhua．Method and construction technology of soft foundation treatment［J］．WestChina Exploration Engineering，2009(1)：2628．

［5］龚晓南．地基处理［M］．北京：中国建筑工业出版社，2005: 148156．

［6］刘海涛，谢新宇，程功，等．刚柔性桩复合地基试验研究［J］．岩土力学, 2005，26(2)： 303306．

LIU Haitao， XIE Xinyu， CHENG Gong，et al． Experimental study of the rigidflexible pile composite foundation［J］． Rock and Soil Mechanics，2005，26(2)：303306．

［7］朱奎，魏纲，徐日庆．刚柔性桩复合地基中桩荷载传递规律试验研究［J］．岩土力学, 2009，30(1)： 201205．

ZHU Kui， WEI Gang， XU Riqing． Research on insitu tests of pile load transfer behaviors in composite foundation with rigid flexible piles［J］． Rock and Soil Mechanics，2009，30(1)：201205.

［8］马骥，张东刚，张震，等．长短桩复合地基设计计算［J］．岩土工程技术, 2001(2)： 8691．

MA Ji，ZHANG Donggang，Zhang Zhen，et al． Design of the composite foundation with longshortpile［J］． Geotechnical Engineering Technique，2001(2)：8691．

［9］李斌．桩体长短与刚度对长短桩复合地基性状影响的模型试验研究［D］．太原：太原理工大学， 2010．

［10］左珅，刘维正，张瑞坤，等．路堤荷载下刚柔长短桩复合地基承载特性研究［J］．西南交通大学学报, 2014(3)：379385．

ZUO Shen， LIU Weizheng，ZHANG Ruikun，et al． Bearing behavior of composite foundation with rigidflexible and longshort piles under embankment load［J］．Journal of Southwest Jiaotong University, 2014(3)： 379385．

［11］Tavenas F， Leroueil S． The behavior of embankment on clay foundation［J］． Canadian Geotechnique， 1980(17)： 236260．

［12］Leroueil S， Magnan J P，Tavenas F． Embankment on soft clays［M］． London： Ellis Horwood Limited，1990: 157170．

［13］Loganathan N，Balasubramaniam A S，Bergado D T．Deformation analysis of embankments［J］．Journal Geotechnical Engineering，1993，119(8): 11851206．

［14］王峰，金武，王宏坤，等．考虑侧向变形影响的客运专线路基沉降的修正［J］．岩土工程学报，2010，32(S2)：245248．

WANG Feng， JIN Wu， WANG Hongkun，et al．Amendment of subgrade settlement of passenger dedicated line considering the lateral deformation effects［J］．Chinese Journal of Geotechnical Engineering，2010，32(S2)：245248．

［15］韩君良，赵岩．高路堤侧向位移沉降特性分析［J］．武汉理工大学学报: 交通科学与工程版, 2012(1)： 165167．

HAN Junliang， ZHAO Yan．Analysis on the settlement characteristic of lateral displacement of the high embankment［J］．Journal of Wuhan University of Technology: Transportation Science & Engineering， 2012(1)： 165167．

［16］丁光文，唐艳．粉喷桩侧向约束在软土地基加固中的运用［J］．路基工程，1999(1)：4950．

DING Guangwen，TANG Yan．Application of powder jet pile for lateral restraint at soft soil foundation treatment［J］．Subgrade Engineering，1999(1)：4950．

［17］吴保全．粉土中格栅结构复合地基的原理与技术方法研究［D］．成都: 成都理工大学，2008．

［18］张军，郑俊杰，马强，等．桩承式加筋路堤挂网技术侧向位移影响分析［J］．华中科技大学学报: 自然科学版，2012，40(1)：6366．

ZHANG Jun， ZHENG Junjie，MA Qiang，et al．Analysis of lateral displacement in fixed geosynthetic technique of geosynthetic reinforced and pile supported embankment［J］．Journal Huazhong University of Science & Technology: Natural Science Edition， 2012，40(1)： 6366．

［19］柏松平，陈兴培，李勇林．侧向限制法软土处理技术研究［J］．公路，2005（7）：127130．

BAI Songping，CHEN Xinpei，LI Yonglin．Study of soft soil treatment technology of lateral restraint［J］．Highway，2005（7）：127130．

［20］吴有平．有无侧向约束夯实水泥土桩复合地基性状对比研究［D］．株洲: 湖南工业大学，2012．

[1]	SHI Kunpeng, ZHENG Yuxing, TIAN Yutao, et al. Design of Ship Model Resistance Experiment Platform [J]. Ocean Engineering Equipment and Technology, 2025, 12(3): 1-10.
[2]	CHEN Peishuai, PAN Yazhou, LIANG Fayun, LI Dejie. Consolidation Characteristics and Bearing Behavior of Sand Pile Composite Foundation in Caisson Heightening [J]. Journal of Shanghai Jiao Tong University, 2021, 55(6): 707-715.
[3]	SONG Xiaolong,ZHAO Wei,NIAN Tingkai,JIAO Houbin. Experiment Simulation of Submarine Clayey Slope Failure Induced by Gas Hydrate Dissociation [J]. Journal of Shanghai Jiaotong University, 2020, 54(1): 43-51.
[4]	WEI Chengxun *(韦承勋), ZHOU Daocheng (周道成), OU Jinping (欧进萍). Wave Forces and Moments on a Gravity Pier Foundation [J]. Journal of Shanghai Jiao Tong University (Science), 2019, 24(3): 305-312.
[5]	XIAO Jing-jing, WANG Chi-ming, ZHANG Shuai, YAO Kai-han. Design of a vector anti-rolling device and its control system [J]. Ocean Engineering Equipment and Technology, 2019, 6(2): 482-486.
[6]	QIAN Peng* (钱鹏), YI Hong (易宏), LI Yinghui (李英辉). The Numerical Simulation of a Towing Cylinder Based on Immersed Body Boundary Method [J]. Journal of shanghai Jiaotong University (Science), 2016, 21(2): 136-142.
[7]	JIAO Jialong, REN Huilong, YU Haicheng. Analysis of Load Characteristics of a Ship in Oblique Regular Waves [J]. Journal of Shanghai Jiao Tong University, 2016, 50(03): 407-412.
[8]	LU Xiang,FENG Zhengping,XU Xuesong. Positioning for Entry Control of Deep-Sea Risers Based on Image Processing [J]. Journal of Shanghai Jiaotong University, 2014, 48(12): 1802-1808.
[9]	Zhi-jun WEI, Shi-lun RUAN, Qian-jin YUE, Bin XIE. Experimental Investigation of Liquid Sloshing Impact Load in a Large-Scale Prismatic Tank [J]. Ocean Engineering Equipment and Technology, 2014, 1(1): 55-61.
[10]	CHEN Zhanyang,REN Huilong，SUN Fangsheng. Model Experiment of Time Distribution of Flare Slamming [J]. Journal of Shanghai Jiaotong University, 2013, 47(06): 904-908.
[11]	JIANG An-Feng-1, LI Rui-Hai-2, WANG Guo-Li-2, FU Zheng-Cai-1. Scale Model Experimental Design on Lightning Shielding Performance of UHVDC Transmission Line [J]. Journal of Shanghai Jiaotong University, 2012, 46(08): 1334-1339.
[12]	LIU Jing-1, LIAN Zhi-Wei-1, CHEN Xu-2, SHI Ding-Yue-2, CHEN An-Yang-2, AN Yu-Hui-2. The Ventilation in Cargo with Reefer Container [J]. Journal of Shanghai Jiaotong University, 2012, 46(03): 468-473.