The Duncan-Chang statistical damage correction model of unsaturated soil considering matric suction
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摘要:
为反映非饱和地基土变形全过程，以某基础工程非饱和土为研究对象，开展固结排水三轴压缩试验。研究发现，非饱和土的偏应力-应变曲线形态近似双曲线，基质吸力对土体力学行为影响十分明显，基质吸力越大，土体偏应力越高。根据非饱和土变形特性及工程特点，选取邓肯-张双曲线模型作为基础模型，引入统计损伤理论，假设非饱和土微元强度服从Weibull概率密度分布，建立邓肯-张统计损伤模型。通过搭建初始切线模量与基质吸力的联系，建立一种新的考虑基质吸力的非饱和土邓肯-张统计损伤模型。给出参数解析方法，得到Weibull分布参数经验表达式，从而修正模型。分析不同基质吸力条件下非饱和土损伤累积规律，采用所建模型和传统邓肯-张模型对比验证非饱和土偏应力-应变试验曲线，证明所建模型的可行性和合理性。研究成果为非饱和土的力学特性研究及辨识模拟提供一定参考。
Abstract:In order to reflect the whole deformation process of unsaturated foundation soil, the consolidated drained triaxial compression test is carried out on the unsaturated soil of a foundation project. It is found that the partial stress-strain curve of unsaturated soil is similar to hyperbola, and the matrix suction has an obvious influence on the mechanical behavior of soil. The greater the matrix suction, the higher the partial stress of soil. According to the deformation characteristics and engineering characteristics of unsaturated soil, the Duncan-Chang hyperbolic model is selected as the basic model, and the statistical damage theory is introduced. Assuming that the micro element strength of unsaturated soil obeys the Weibull probability density distribution, the Duncan-Chang statistical damage model is established. By establishing the relationship between the initial tangent modulus and matrix suction, a new Duncan-Chang statistical damage model of the unsaturated soil considering matrix suction is established. The parameter analysis method is given, and the empirical expression of the Weibull distribution parameters is obtained, which is used to modify the model. The damage accumulation law of unsaturated soil under different matrix suction conditions is analyzed, and the partial stress-strain test curve of unsaturated soil is compared with the traditional Duncan-Chang model, which proves the feasibility and rationality of the model. The research results provide a certain reference for the study of mechanical properties and identification simulation of unsaturated soil.
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Key words:
- unsaturated soil /
- matric suction /
- initial tangent modulus /
- Duncan-Chang model /
- statistical damage
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表 1 Eu和b值
Table 1. Eu and b values
s/kPa Eu/MPa b/10−4 100 16.113 22.436 200 23.684 16.628 300 33.601 12.041 400 37.583 9.747 
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表 2 参数m和F0值
Table 2. Values of parameters m and F0
s/kPa m F0/kPa β R2 100 0.364 385.720 −1.569 0.9762 200 0.487 527.936 −2.376 0.9841 300 0.612 656.831 −4.083 0.9825 400 0.793 703.367 −5.954 0.9763
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[1] 李修磊, 陈洪凯, 李金凤, 等. 基于非饱和土强度理论的土质边坡浅层破坏稳定性分析[J]. 工程科学与技术,2019,51(2):61 − 70. [LI Xiulei, CHEN Hongkai, LI Jinfeng, et al. Stability analysis on shallow layer failure of soil slope based on unsaturated soil strength theory[J]. Advanced Engineering Sciences,2019,51(2):61 − 70. (in Chinese with English abstract)
[2] LLORET-CABOT M, WHEELER S J, SÁNCHEZ M. A unified mechanical and retention model for saturated and unsaturated soil behaviour[J]. Acta Geotechnica,2017,12(1):1 − 21. doi: 10.1007/s11440-016-0497-x
[3] 陈正汉, 郭楠. 非饱和土与特殊土力学及工程应用研究的新进展[J]. 岩土力学,2019,40(1):1 − 54. [CHEN Zhenghan, GUO Nan. New developments of mechanics and application for unsaturated soils and special soils[J]. Rock and Soil Mechanics,2019,40(1):1 − 54. (in Chinese with English abstract)
[4] HAYATI E, ABDI E, SARAVI M M, et al. Temporal pattern of soil matric suction in the unsaturated soil slope under different forest cover[C]// European Geosciences Union General Assembly, 2017.
[5] 刘东燕, 郑志明, 侯龙, 等. 路基非饱和土抗剪强度的吸力效应[J]. 土木建筑与环境工程,2012,34(4):1 − 5. [LIU Dongyan, ZHENG Zhiming, HOU Long, et al. Matric suction effect on shear strength of roadbed unsaturated soil[J]. Journal of Civil, Architectural & Environmental Engineering,2012,34(4):1 − 5. (in Chinese with English abstract)
[6] 孙德安. 饱和度对非饱和土力学性质的影响[J]. 岩土力学, 2009, 30(增刊2): 13−16. [SUN De’an. Effect of saturation degree on mechanical behaviours of unsaturated soils[J]. Rock and Soil Mechanics, 2009, 30(Sup 2): 13−16. (in Chinese with English abstract)]
[7] 宋友建, 胡新丽, 郭利娜, 等. 吸力路径对非饱和土力学性质的影响[J]. 水文地质工程地质,2013,40(5):64 − 68. [SONG Youjian, HU Xinli, GUO Lina, et al. Effect of suction path on mechanical behaviors of unsaturated soils[J]. Hydrogeology & Engineering Geology,2013,40(5):64 − 68. (in Chinese with English abstract)
[8] 刘文化. 干湿循环对非饱和土力学特性影响及非饱和土本构关系探讨[D]. 大连: 大连理工大学, 2015.
LIU Wenhua. Effect of drying/wetting on the mechanical behaviors of unsaturated soils and study on the constitutive relationship of unsaturated soils[D]. Dalian: Dalian University of Technology, 2015. (in Chinese with English abstract)
[9] 杨庆. 初始状态对非饱和土力学特性的影响研究[C]// 非饱和土的应力—强度理论与变形特性学术研讨会, 2016.
YANG Qing. Influence of initial state on mechanical properties of unsaturated soil[C]// Symposium on stress strength theory and deformation characteristics of unsaturated soils, 2016. (in Chinese with English abstract)
[10] 张庆海. 基于冻融干湿作用的非饱和黄土力学性质试验及工程应用研究[D]. 兰州: 兰州理工大学, 2018.
ZHANG Qinghai. Study on mechanical properties experiment and engineering application of unsaturated loess based on freeze-thaw and dry-wet[D]. Lanzhou: Lanzhou University of Technology, 2018. (in Chinese with English abstract)
[11] 赵成刚, 刘艳, 周贵荣, 等. 非饱和土本构模型研究进展[J]. 北京工业大学学报,2008,34(8):820 − 829. [ZHAO Chenggang, LIU Yan, ZHOU Guirong, et al. Research progress of constitutive models for unsaturated soils[J]. Journal of Beijing University of Technology,2008,34(8):820 − 829. (in Chinese with English abstract)
[12] 魏建柄, 刘卫斌. 非饱和土蠕变力学特性试验及经验模型研究[J]. 水文地质工程地质,2019,46(6):67 − 73. [WEI Jianbing, LIU Weibin. An experimental study of the creep mechanical properties of unsaturated soil and empirical models[J]. Hydrogeology & Engineering Geology,2019,46(6):67 − 73. (in Chinese with English abstract)
[13] FAROUK A, LAMBOJ L, KOS J. A numerical model to predict matric suction inside unsaturated soils[J]. Acta Polytechnica,2004,44(4):4 − 10. doi: 10.14311/588
[14] 李顺群, 栾茂田, 杨庆. 考虑基质吸力变化时非饱和土的一维本构模型[J]. 岩土力学,2006,27(9):1575 − 1578. [LI Shunqun, LUAN Maotian, YANG Qing. One-dimensional constitutive model of unsaturated soil considering change of matric suction[J]. Rock and Soil Mechanics,2006,27(9):1575 − 1578. (in Chinese with English abstract) doi: 10.3969/j.issn.1000-7598.2006.09.030
[15] HAMID T B, MILLER G A. A constitutive model for unsaturated soil interfaces[J]. International Journal for Numerical and Analytical Methods in Geomechanics,2008,32(13):1693 − 1714. doi: 10.1002/nag.692
[16] 秦冰, 陈正汉, 方振东, 等. 基于混合物理论的非饱和土的热-水-力耦合分析模型Ⅰ[J]. 应用数学和力学,2010,31(12):1476 − 1488. [QIN Bing, CHEN Zhenghan, FANG Zhendong, et al. Analysis of coupled thermo-hydro-mechanical behavior of unsaturated soils based on theory of mixtures Ⅰ[J]. Applied Mathematics and Mechanics,2010,31(12):1476 − 1488. (in Chinese with English abstract) doi: 10.3879/j.issn.1000-0887.2010.12.008
[17] 杨明辉, 孙龙, 赵明华, 等. 基于统计损伤理论的非饱和土简易本构模型[J]. 水文地质工程地质,2015,42(3):43 − 48. [YANG Minghui, SUN Long, ZHAO Minghua, et al. A simplified unsaturated soil constitutive model based on statistical damage theory[J]. Hydrogeology & Engineering Geology,2015,42(3):43 − 48. (in Chinese with English abstract)
[18] 章志荣. 非饱和土的三剪统一弹塑性本构模型研究[D]. 南昌: 南昌大学, 2019.
ZHANG Zhirong. Approaches to the triple-shear unified elasto-plastic constitutive models for unsaturated soils[D]. Nanchang: Nanchang University, 2019. (in Chinese with English abstract)
[19] JEAN L. How to use damage mechanics[J]. Nuclear Engineering and Design,1984,80(2):233 − 245. doi: 10.1016/0029-5493(84)90169-9
[20] 李俊玲, 卢芳云, 赵鹏铎, 等. 含能材料的损伤本构模型研究进展[J]. 含能材料,2010,18(2):229 − 235. [LI Junling, LU Fangyun, ZHAO Pengduo, et al. Progress in the constitutive models including damage of energetic materials[J]. Chinese Journal of Energetic Materials,2010,18(2):229 − 235. (in Chinese with English abstract) doi: 10.3969/j.issn.1006-9941.2010.02.024
[21] 孙龙. 非饱和土统计损伤本构模型试验研究及工程应用[D]. 长沙: 湖南大学, 2014.
SUN Long. Test research and engineering applications of unsaturated soil constitutive model based on statistical damage theory[D]. Changsha: Hunan University, 2014. (in Chinese with English abstract)
[22] JANBU N. Soil compressibility as determined by oedometer and triaxial tests[C]// Proceedings of European Conference on Soil Mechanics and Foundation Engineering, Wiesbaden, 1963, 1: 19−25.
[23] 祝艳波, 余宏明. 巴东组碎屑土夹层的非饱和蠕变经验模型[J]. 中国公路学报,2016,29(4):22 − 29. [ZHU Yanbo, YU Hongming. Empirical unsaturated creep models for weak intercalated soils of Badong formation[J]. China Journal of Highway and Transport,2016,29(4):22 − 29. (in Chinese with English abstract) doi: 10.3969/j.issn.1001-7372.2016.04.004
[24] 张芳枝, 陈晓平. 非饱和黏土变形和强度特性试验研究[J]. 岩石力学与工程学报,2009,28(增刊2):3808 − 3814. [ZHANG Fangzhi, CHEN Xiaoping. Experimental study on characteristics of deformationand strength of unsaturated clay[J]. Chinese Journal of Rock Mechanics and Engineering,2009,28(Sup2):3808 − 3814. (in Chinese with English abstract)
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