卸荷土体本构模型选用及其参数的确定——以港珠澳大桥拱北隧道明挖段基坑为例

柳志平; 刘泉声; 程勇; 贾瑞华; 蒋景东

卸荷土体本构模型选用及其参数的确定——以港珠澳大桥拱北隧道明挖段基坑为例 English Version

(1. 武汉大学土木建筑工程学院，湖北武汉 430072；2. 中交第二公路勘察设计研究院有限公司，湖北武汉 430056 )

详细信息

作者简介:
柳志平(1985– )，男，湖北黄冈人，博士研究生，从事基坑设计及地基处理等方面研究。

中图分类号: TU473
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- 收稿日期: 2012-11-12
- 发布日期: 2012-11-12

Selection and parametric determination of constitutive model for unloading soil—Case study of foundation pit at open excavation section of Gongbei tunnel of Hongkong-Zhuhai-Macau Bridge

(1. School of Civil Engineering & Architecture, Wuhan University, Wuhan 430072, China; 2. CCCC Second Highway Consultants Co., Ltd., Wuhan 430056, China)

摘要

摘要: 对卸荷土体工程性质的认识是解决基坑开挖工程中问题的关键，港珠澳大桥连接线珠海拱北隧道处于海相软黏土地层，基坑开挖深度大，断面宽，研究该基坑土体在卸荷应力路径下的土体本构模型及其参数，对工程设计有着重要的意义。取现场土样，选定海相沉积的淤泥质土和可塑状粉质黏土作为研究对象，测定其K0值，采用应力控制式三轴仪，在围压100，200，400，600 kPa状态下进行K0排水固结，对固结完成的土样进行不同应力路径的卸荷试验，根据应力–应变关系曲线的非线性特征，采用邓肯张E–μ模型作为该基坑土体的本构模型，依照试验结果，分别确定邓肯张E–μ模型的8个基本参数，为基坑有限元分析提供重要依据。
- 基坑 /
- 卸荷试验 /
- 邓肯张模型 /
- 模型参数
Abstract: The understanding of engineering properties of unloading soil is the key to solving the problems in excavation of foundation pits. Gongbei tunnel in Zhuhai of Hongkong-Zhuhai-Macau Bridge is located in marine facies soft clay. The excavation depth and width of its foundation pit are both very large. The researches on of constitutive model and model parameters of the foundation pit soil under unloading stress path are of great significance to the engineering design. The marine faces sediment-mucky soil and plastic silty clay are are studied so as to determine their K0 coefficients. K0 drained consolidation expririments are performed under the confining pressures of 100, 200, 400 and 600 kPa by using the stress controlled triaxial apparatus. Unloading tests with various stress paths are conducted after the soil samples are completely consolidated. According to the non-linear feature of stress-strain relationship curve, the Duncan-Zhang E-μ model is adopted as the constitutive model for soil. According to the experimental results, 8 basic parameters are determined, and this study provides important basis for the FEM analysis of the foundation pit. |
- foundation pit /
- unloading test /
- Ducan-Zhang model /
- model parameter

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参考文献(15)

[1]	LAMBE T W. Stress path method[J]. Journal of the soil Mechanics and Foundation Division ASCE, 1967, 93(SM6): 309–331.
[2]	曾国熙, 潘秋元, 胡一峰. 软黏土地基基坑开挖性状的研究[J]. 岩土工程学报, 1958, 10(3): 13–22. (ZENG Guo-xi, PAN Qiu-yuan, HU Yi-feng. The behavior of excavation in soft clay ground[J]. Chinese Journal of Geotechnical Engineering, 1958, 10(3): 13–22. (in Chinese))
[3]	何世秀, 韩高升, 庄心善, 等. 基坑开挖卸荷土体变形的试验研究[J]. 岩土力学学报, 2003, 24(1): 17–20. (He Shi-xiu, HAN Gao-sheng, ZHUANG Xin-shan, et al. Experimental researches on unloading deformation of clay in excavation of foundation pit[J]. Rock and Soil Mechanics, 2003, 24(1): 17–20.(in Chinese))
[4]	周秋娟. 软土卸荷力学特性及软弱地层中基坑稳定性研究[D]. 广州暨南大学, 2009. (ZHOU Qiu-juan. Research on mechanical characteristics of soft soil under unloading and stability of foundation on weak underground[D]. Guangzhou Ji'nan University, 2009. (in Chinese))
[5]	付建军. 二元地质环境下狭长型基坑围护体系与防渗体系研究[D]. 武汉: 中国科学院武汉岩土力学研究所, 2010. (FU Jian-jun Study on Long–narrow Foundation Enclosure System and Impervious System in the Environment of Binary Geological[D]. Wuhan: Institute of Rock and Mechanics, Chinese Academy of Sciences, 2010.6. (in Chinese))
[6]	高江平, 李芳. 黄土邓肯张模型有限元计算参数的试验[J]. 长安大学学报(自然科学版), 2006, 26(2): 11–14. (GAO Jiang-ping, LI Fang. Experiments on parameters of Duncan Chang Model for Loess[J]. Journal of Chang'an University (Natural Science Edition), 2006, 26(2): 11–14. (in Chinese))
[7]	NAGARAJ T S M K, SRIDHARAN A. Incremental Loading device for stress path and strength testing of soils[J]. Geotechnical Testing Journal, 1981, 4(2): 35–46.
[8]	矫德全, 陈俞炯. 土的各项异性和卸荷体缩[J]. 岩土工程学报, 1994, 16(4): 9–15. (JIAO De-quan, CHEN Yu-jiong. Anisotropy and volume-contraction of soil due to axial unloading in CD test[J]. Chinese Journal of Geotechnical Engineering, 1994, 16(4): 9–15. (in Chinese))
[9]	李广信, 郭瑞平. 土的卸荷体缩与可恢复剪胀[J]. 岩土工程学报, 2000, 22(2): 158–161. (LI Guang-xin, GUO Rui-ping. Volume-contraction in unloading of shear tests and reversible Engineering[J]. Chinese Journal of Geotechnical Engineering, 2000, 22(2): 158–161. (in Chinese))
[10]	李广信, 武世锋. 土的卸荷体缩的试验研究及其机理探讨[J]. 岩土工程学报， 2002, 24(1): 47–50. (LI Guang-xin, WU Shi-feng. Experimental research on volume-contraction of soil under unloading and examination of its mechanism[J]. Chinese Journal of Geotechnical Engineering, 2002, 24(1): 47–50. (in Chinese))
[11]	常银生. 黏性土应力路径的试验研究与分析[D]. 南京: 南京工业大学, 2005. (CHANG Ying-sheng. Experimental study and analysis of stress path for cohesive soil[D]. Nanjing: Nanjing University of Technology, 2005. (in Chinese))
[12]	刘国斌, 侯学渊. 软土的卸荷模量[J]. 岩土工程学报, 1996, 18(6): 18–23. (LIU Guo-bin, HOU Xue-yuan. Unloading modulus of the Shanghai soft clay[J]. Chinese Journal of Geotechnical Engineering, 1996, 18(6): 18–23. (in Chinese))
[13]	刘国斌, 侯学渊. 软土的卸荷载应力–应变特性[J]. 地下工程与隧道, 1997(2): 16–23. (LIU Guo-bin, HOU Xue-yuan. Unloading stress-strain characteristics of the soft clay[J]. Underground Engineering and Tunnel, 1997(2): 16–23. (in Chinese))
[14]	童华炜, 邓祎文. 土体K0固结–卸荷剪切试验研究[J]. 工程勘察, 2008(5): 13–16. (TONG Hua-wei, DENG Yi-wen. The experimental study on the K0 consolidation-lateral unloading of the soil[J]. Geotechnical Investigation & Surveying, 2008(5): 13–16. (in Chinese))
[15]	童华炜. 考虑卸荷应力路径的基坑开挖土体变形研究[J]. 建筑科学, 2008, 21(7): 35–38. (TONG Hua-wei. Researches on soil deformations in foundation pit excavation by triaxial unloading path test[J]. Building Science, 2008, 21(7): 35–38. (in Chinese))

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卸荷土体本构模型选用及其参数的确定——以港珠澳大桥拱北隧道明挖段基坑为例 English Version

作者简介: 柳志平(1985– )，男，湖北黄冈人，博士研究生，从事基坑设计及地基处理等方面研究。

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出版历程

Selection and parametric determination of constitutive model for unloading soil—Case study of foundation pit at open excavation section of Gongbei tunnel of Hongkong-Zhuhai-Macau Bridge

计量

出版历程

目录

作者简介:
柳志平(1985– )，男，湖北黄冈人，博士研究生，从事基坑设计及地基处理等方面研究。