Test on the Horizontal Characteristics of Disconnected Piled Raft Foundation

ZHU Xiao-jun, KONG Wei-yang, GONG Wei-ming, LI Wen-shuai, FEI Kang

China Journal of Highway and Transport ›› 2019, Vol. 32 ›› Issue (2) : 97-105,115.

PDF Full Text Download(2841 KB)
PDF Full Text Download(2841 KB)
China Journal of Highway and Transport ›› 2019, Vol. 32 ›› Issue (2) : 97-105,115.
Bridge Engineering

Test on the Horizontal Characteristics of Disconnected Piled Raft Foundation

  • ZHU Xiao-jun1,2, KONG Wei-yang1, GONG Wei-ming2, LI Wen-shuai1, FEI Kang1
Author information +
History +

Abstract

To provide reference for the design and construction of disconnected piled rafts (DPRs), specifically aiming at the seismic isolation foundation of DPRs, which has been widely adopted in large scale bridge construction, by considering the influences of vertical load and cushion thickness, the horizontal bearing characteristics of DPRs were studied by conducting a laboratory test. Particle image velocimetry was used to track the horizontal soil displacement path, and the displacement field and shear zone were obtained using the digital image correlation (DIC) technique. The influences of vertical load and cushion thickness on the horizontal displacement of the raft, pile bending moment, and shear force were analyzed. A simplified model and calculation method for obtaining the lateral bearing capacity of DPRs were proposed and verified with the test data. Results demonstrate that the vertical load on raft could limit the horizontal displacement of the rafts, whereas the pile bending moment and the shear force reduced with a reduction in the thickness of the cushion, which was positioned between the raft and the pile head. The soil concentration zone formed at the top of the cushion and the local plastic deformation zone then appeared and expanded continuously. Toward the end, the local plastic deformation zones penetrated to form an overall shear zone. The lateral bearing capacity of DPRs was dependent on the friction between the raft and the cushion or the horizontal bearing capacity of the cushion, which was related to the vertical load on the raft. This conclusion corresponds to the cushion failure mode obtained by the DIC technique. Therefore, the bending moment and the shear force can be reduced by adjusting the cushion thickness during the design and engineering applications of the DPRs. The revelation of the failure mode of the cushion under a horizontal load can be used as the reference for the design and research of vibration isolation foundation in large-scale bridge.

Key words

bridge engineering / piled raft foundation / model test / gravel cushion / horizontal characteristic / failure mode

Cite this article

EndNote

Ris (Procite)

Bibtex

Download Citations
ZHU Xiao-jun, KONG Wei-yang, GONG Wei-ming, LI Wen-shuai, FEI Kang. Test on the Horizontal Characteristics of Disconnected Piled Raft Foundation[J]. China Journal of Highway and Transport, 2019, 32(2): 97-105,115

References

[1] POULOS H G. Piled Raft Foundations Design and Applications[J]. Géotechnique, 2001, 51 (2):95-113.
[2] MALI S, SINGH B. Behavior of Large Piled-raft Foundation on Clay Soil[J]. Ocean Engineering, 2018, 149:205-216.
[3] CAO X D, WONG I H, CHANG M F. Behavior of Model Rafts Resting on Pile-reinforced Sand[J]. Journal of Geotechnical and Geoenvironmental Engineering, 2004, 130 (2):129-138.
[4] LIANG F Y, CHEN L Z, SHI X G. Numerical Analysis of Composite Piled Raft with Cushion Subjected to Vertical Load[J]. Computers and Geotechnics, 2003, 30 (6):443-453.
[5] 陈龙珠,梁发云,黄大治,等.高层建筑应用长-短桩复合地基的现场试验研究[J].岩土工程学报,2004,26(2):167-171. CHEN Long-zhu, LIANG Fa-yun, HUANG Da-zhi, et al. Field Study on Behavior of Composite Piled Raft Foundation for High-rise Buildings[J]. Chinese Journal of Geotechnical Engineering, 2004, 26 (2):167-171.
[6] SINHA A, HANNA A M. 3D Numerical Model for Piled Raft Foundation[J]. International Journal of Geomechanics, 2017, 17 (2):04016055.
[7] TRADIGO F, PISANO F, DI PRISCO C, et al. Non-linear Soil-structure Interaction in Disconnected Piled Raft Foundations[J]. Computers and Geotechnics, 2015, 63:121-134.
[8] TRADIGO F, PISANO F, DI PRISCO C. On the Use of Embedded Pile Elements for the Numerical Analysis of Disconnected Piled Rafts[J]. Computers and Geotechnics, 2016, 72:89-99.
[9] ZHOU F, LIN C, WANG X D, et al. Application of Deformation Adjustors in Piled Raft Foundations[J]. Proceedings of the Institution of Civil Engineerings:Geotechnical Engineering, 2016, 169 (6):1-14.
[10] HAMADA J, TSUCHIVA T, TANIKAWA T, et al. Lateral Loading Tests on Piled Rafts and Simplified Method to Evaluate Sectional Forces of Piles[J]. Geotechnical Engineering Journal of the SEAGS & AGSSEA, 2015, 46 (2):29-42.
[11] SAWADA K, TAKEMURA J. Centrifuge Model Tests on Piled Raft Foundation in Sand Subjected to Lateral and Moment Loads[J]. Soils and Foundations, 2014, 54 (2):126-140.
[12] 郑 刚,刘双菊,伍止超,等.刚性桩复合地基在水平荷载作用下工作性状的模型试验[J].岩土工程学报,2005,27(8):865-868. ZHENG Gang, LIU Shuang-ju, WU Zhi-chao, et al. Experimental Study on Behavior of Rigid Pile Composite Ground Under Horizontal Load[J]. Chinese Journal of Geotechnical Engineering, 2005, 27 (8):865-868.
[13] 朱世哲,徐日庆,杨晓军,等.带垫层刚性桩复合地基桩土应力比的计算与分析[J].岩土力学,2004,25(5):814-818.ZHU Shi-zhe, XU Ri-qing, YANG Xiao-jun, et al. Computation and Analysis of Ratio of Pile Stress to Soil Stress of Rigid Pile Composite Foundation with Cushion[J]. Rock and Soil Mechanics, 2004, 25 (5):814-818.
[14] 吴春林,闫明礼,杨军,等.CFG桩及其复合地基水平荷载作用下的性状[J].工程勘察,1996(4):18-21.WU Chun-lin, YAN Ming-li, YANG Jun, et al. Behavior of CFG Pile Composite Foundation Under Lateral Load[J]. Geotechnical Investigation and Surveying, 1996 (4):18-21.
[15]戚科骏,宰金珉,梅国雄,等.群桩复合地基褥垫层效用的数值分析[J].岩石力学与工程学报,2004,23(1):4590-4593.QI Ke-jun, ZAI Jin-min, MEI Guo-xiong, et al. Numerical Analysis on Effects of Cushion of Composite Found with Pile Group[J]. Chinese Journal of Rock Mechanics and Engineering Mechanics, 2004, 23 (1):4590-4593.
[16]宰金珉,凌华,王旭东.桩筏基础非线性共同作用数值分析[J].南京工业大学学报,2002,24(5):1-7.ZAI Jin-min, LIN Hua, WANG Xu-dong. Numerical Analysis of Nonlinear Interaction of Piled Raft Foundation[J]. Journal of Nanjing University of Technology, 2002, 24 (5):17.
[17]刘汉龙,陶学俊,张建伟,等.水平荷载作用下PCC桩复合地基工作性状[J].岩土力学,2010,31(9):2716-2722.LIU Han-long, TAO Xue-jun, ZHANG Jian-wei, et al. Behavior of PCC Pile Composite Foundation Under Lateral Load[J]. Rock and Soil Mechanics, 2010, 31 (9):2716-2722.
[18]孔纲强,杨庆,郑鹏一,等.考虑时间效应的群桩负摩阻力模型试验研究[J].岩土工程学报,2009,31(12):1913-1919. KONG Gang-qiang, YANG Qing, ZHENG Peng-yi, et al. Model Test on Negative Skin Friction for Pile Groups Considering Time Effect[J]. Chinese Journal of Geotechnical Engineering, 2009, 31 (12):1913-1919.
[19]李元海,朱合华,上野胜利,等.基于图像相关分析的砂土模型试验变形场量测[J].岩土工程学报,2004,26(1):36-41.LI Yuan-hai, ZHU He-hua, KATSUTOSHI U, et al.Deformation Field Measurement for Granular Soil Model Using Image Analysis[J]. Chinese Journal of Geotechnical Engineering, 2004, 26 (1):36-41.
PDF Full Text Download(2841 KB)

1511

Accesses

0

Citation

Detail
Sections
Recommended
Copyright © China Journal of Highway and Transport, All Rights Reserved.
Tel: 029-82334387　
E-mail：zgglxb@163.com
Powered by Beijing Magtech Co. Ltd,.

/

〈 〉