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摘要:
土-水特征曲线是非饱和土入渗和流-固耦合分析的基础，目前该模型的研究成果由于试验方法和设备的局限，仅能够得到局部基质吸力段（低吸力或高吸力）的土-水特征曲线；而如何根据局部试验数据集推断与试验结果相吻合的全基质吸力段范围的土-水特征曲线是一个难题。对东南沿海广泛分布的原状残积土进行了不同基质吸力段的土-水特征试验。根据残积土低吸力段和高吸力段的试验数据，运用可靠度分析方法，从土壤孔隙微元破裂失稳的角度，建立了土壤全基质吸力段的土-水特征模型。根据UNSODA2.0数据库提取砂土、粉土、黏土等3种类型土样本（52个）的试验数据，讨论了模型参数意义和不同土类的模型适用性，进行了不同土-水特征模型的比较分析。对比验证研究表明，形状参数σ和中值比例参数
$ \mu $ Abstract:Soil–water characteristic curves (SWCCs) are considered as a basis for analyzing fluid–solid coupling of unsaturated soil. How to estimate the SWCC over the whole region with matric suction based on the limited local datasets is challenging. Laboratory test is separately carried out on the ranges with low and high matric suctions of the undisturbed residual soil widely distributed in southeast China. With the test data, a model for SWCCs of soil in the whole range with matric suction is established by applying the reliability analysis method. Through analysis and verification based on the test data and data of 52 samples of three types of soil (sand, silt-loam and clay) obtained from UNSODA, it is found that the model parameters involved in the model show significant physics meaning. The model can be used to estimate the SWCC of soil within the whole range with matric suction according to part of the data (in the low or high matric suction part). Compared with the other models, the model is robust and is applicable for acquiring SWCCs of different types of soil within the whole range matric suction with R2>0.98. In addition, the model provides an important method to obtain SWCCs of soils with different texture, and is of the reference significance to the geotechnical AI analysis.
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Key words:
- soil water characteristic curve /
- residual clay /
- matric suction /
- fully matric suction /
- reliability
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表 1 残积土的物理性质
Table 1. Physical properties of the residual clay profiles
性质 均值 密度/(g·cm−3) 1.48 初始含水率w/ % 15 重度G/ (kN·m−3) 14.5 孔隙率e 0.79 塑限/% 30.3 液限/% 41.4 有机质含量/% 0.5 级配系数CU 8.75 曲率系数CC 1.21 有效粒径D10/ mm 0.008 平均粒径D50/ mm 0.050 
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表 2 基质吸力空间的不同概率描述
Table 2. Different probability distribution models for the test data
编号 概率分布 低基质吸力段组 高基质吸力段组 全基质吸力段 MLE a MLE b R2(1) MLE a MLEb R2(2) MLE a MLE b R2(3) 1 伽马分布 0.38 2234.09 0.9562 0.13 33749.73 0.7628 0.28 7206.14 0.9284 2 广义极值分布 548.59 362.22 0.9753 6123.45 28758.52 0.6014 1103.94 906.40 0.957 3 对数正态分布 5.61 2.77 0.9804 5.64 3.05 0.9721 5.68 2.93 0.9776 4 瑞利分布 315.38 / 0.9104 894.77 / 0.8290 318.16 / 0.9148 5 韦伯分布 627.39 0.47 0.9645 1834.35 3.48 0.4666 948.58 0.37 0.9464 6 指数分布 385.42 / 0.8355 1330.13 / 0.6928 470.04 / 0.8288 7 正态分布 384.85 428.29 0.9782 2043.83 2777.75 0.5672 643.19 886.78 0.9652
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表 3 UNSODA不同土壤特征试验数据
Table 3. Basic information of the selected soil data from UNSODA
类型 样本数 UNSODA 编码 数值 密度/ (g·cm−3) 粒径试验组数 土-水试验组数 砂土 31 1140 1141 1142 1465
1466 1467 2221 2310 3132 3141 3142 3143
3144 3153 3154 3155 3162 3163 3164 3165
3172 3173 3174 3181 3206 4440 4441 4444
4520 4521 4522均值 1.58 8 15 最大值 1.81 16 42 最小值 1.43 6 10 粉砂土 9 2404 2405 2760 2761
3260 3261 4071 4570
4671均值 1.38 5 13 最大值 1.56 9 25 最小值 1.13 3 7 黏性土 12 1400 2361 2362 2620
2621 2660 3281 3282 4120 4121 4680 4681均值 1.25 6 13 最大值 1.61 9 25 最小值 1.03 3 7
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表 4 土-水特征曲线模型
Table 4. Different models for the soil characteristic curve
模型 公式 Gardner (1956) 
Brooks and Corey (1964) 
Fredlund and Xing (1994) 
Van Genuchten (1980) 
Kosugi (1994) 
McKee and Bumb (1987)
(Boltzman )
注：S是饱和度， 
是基质吸力值，
、
、
是模型参数。
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[1] FREDLUND D, HOUSTON S. Interpretation of soil-water characteristic curves when volume change occurs as soil suction is changed[C]// Advances in Unsaturated Soils - Proceedings of the 1st Pan-American Conference on Unsaturated Soils, PanAmUNSAT 2013. Colombia: CRC Press, 2013: 15 − 31.
[2] FREDLUND D G, XING A Q, HUANG S Y. Predicting the permeability function for unsaturated soils using the soil-water characteristic curve[J]. Canadian Geotechnical Journal,1994,31(4):533 − 546. doi: 10.1139/t94-062
[3] FREDLUND D G, RAHARDJO H, FREDLUND M D. Unsaturated soil mechanics in engineering practice[J]. Unsaturated Soil Mechanics in Engineering Practice,2012,132(3):286 − 321.
[4] HAN Z, VANAPALLI S K, ZOU W L. Integrated approaches for predicting soil-water characteristic curve and resilient modulus of compacted fine-grained subgrade soils[J]. Canadian Geotechnical Journal,2017,54(5):646 − 663. doi: 10.1139/cgj-2016-0349
[5] KOSUGI K, HOPMANS J W. Scaling water retention curves for soils with lognormal pore-size distribution[J]. Soil Science Society of America Journal,1998,62(6):1496 − 1505. doi: 10.2136/sssaj1998.03615995006200060004x
[6] MERAT S, DJERBAL L, BAHAR R. Numerical analysis of climate effect on slope stability[C]//Second Pan-American Conference on Unsaturated Soils. November 12-15, 2017, Dallas, Texas. Reston: American Society of Civil Engineers, 2017: 308 − 318.
[7] 徐全, 谭晓慧, 辛志宇, 等. 土水特征曲线的概率分析[J]. 水文地质工程地质,2015,42(3):79 − 85. [XU Quan, TAN Xiaohui, XIN Zhiyu, et al. Probabilistic analysis of the soil-water characteristic curve[J]. Hydrogeology & Engineering Geology,2015,42(3):79 − 85. (in Chinese with English abstract)
[8] BORDONI M, BITTELLI M, VALENTINO R, et al. Improving the estimation of complete field soil water characteristic curves through field monitoring data[J]. Journal of Hydrology,2017,552:283 − 305. doi: 10.1016/j.jhydrol.2017.07.004
[9] JOHARI A, HABIBAGAHI G, GHAHRAMANI A. Prediction of SWCC using artificial intelligent systems: a comparative study[J]. Scientia Iranica,2011,18(5):1002 − 1008. doi: 10.1016/j.scient.2011.09.002
[10] GARDNER W R, HILLEL D, BENYAMINI Y. Post-irrigation movement of soil water: 1. redistribution[J]. Water Resources Research,1970,6(3):851 − 861. doi: 10.1029/WR006i003p00851
[11] BROOKS R, COREY A. Hydraulic properties of porous media[J]. Hydrology Papers,1964,3(3):37.
[12] MUALEM Y. A new model for predicting the hydraulic conductivity of unsaturated porous media[J]. Water Resources Research,1976,12(3):513 − 522. doi: 10.1029/WR012i003p00513
[13] FREDLUND D G, XING A Q. Equations for the soil-water characteristic curve[J]. Canadian Geotechnical Journal,1994,31(4):521 − 532. doi: 10.1139/t94-061
[14] VAN GENUCHTEN M T. A closed-form equation for predicting the hydraulic conductivity of unsaturated soils[J]. Soil Science Society of America Journal,1980,44(5):892 − 898. doi: 10.2136/sssaj1980.03615995004400050002x
[15] GALLIPOLI D, WHEELER S J, KARSTUNEN M. Modelling the variation of degree of saturation in a deformable unsaturated soil[J]. Géotechnique,2003,53(1):105 − 112.
[16] CIERVO F, CASINI F, PAPA M N, et al. Some remarks on bimodality effects of the hydraulic properties on shear strength of unsaturated soils[J]. Vadose Zone Journal,2015,14(9):1 − 12. doi: 10.2136/vzj2014.09.0126
[17] GHORBANI J, AIREY D W, EL-ZEIN A. Numerical framework for considering the dependency of SWCCs on volume changes and their hysteretic responses in modelling elasto-plastic response of unsaturated soils[J]. Computer Methods in Applied Mechanics and Engineering,2018,336:80 − 110. doi: 10.1016/j.cma.2018.03.008
[18] 潘登丽, 倪万魁, 苑康泽, 等. 基于VG模型确定土水特征曲线基本参数[J]. 工程地质学报,2020,28(1):69 − 76. [PAN Dengli, NI Wankui, YUAN Kangze, et al. Determination of soil-water characteristic curve variables based on vg model[J]. Journal of Engineering Geology,2020,28(1):69 − 76. (in Chinese with English abstract)
[19] 陈东霞, 龚晓南. 非饱和残积土的土-水特征曲线试验及模拟[J]. 岩土力学,2014,35(7):1885 − 1891. [CHEN Dongxia, GONG Xiaonan. Experiment and modeling of soil-water characteristic curve of unsaturated residual soil[J]. Rock and Soil Mechanics,2014,35(7):1885 − 1891. (in Chinese with English abstract)
[20] 伊盼盼, 牛圣宽, 韦昌富. 干密度和初始含水率对非饱和重塑粉土土水特征曲线的影响[J]. 水文地质工程地质,2012,39(1):42 − 46. [YI Panpan, NIU Shengkuan, WEI Changfu. Effect of dry density and initial moisture content on soil water characteristic curve of remolded unsaturated silt[J]. Hydrogeology & Engineering Geology,2012,39(1):42 − 46. (in Chinese with English abstract)
[21] 张爱军, 王毓国, 邢义川, 等. 伊犁黄土总吸力和基质吸力土水特征曲线拟合模型[J]. 岩土工程学报,2019,41(6):1040 − 1049. [ZHANG Aijun, WANG Yuguo, XING Yichuan, et al. Fitting models for soil-water characteristic curve of total and matrix suctions of Yili loess[J]. Chinese Journal of Geotechnical Engineering,2019,41(6):1040 − 1049. (in Chinese with English abstract)
[22] ALDAOOD A, BOUASKER M, AL-MUKHTAR M. Soil-water characteristic curve of lime treated gypseous soil[J]. Applied Clay Science,2014,102:128 − 138. doi: 10.1016/j.clay.2014.09.024
[23] 尹振华, 张建明, 张虎, 等. 融化压缩下水泥改良冻土的微观孔隙特征演变[J]. 水文地质工程地质,2021,48(2):97 − 105. [YIN Zhenhua, ZHANG Jianming, ZHANG Hu, et al. Microcosmic pore characteristics evolution of the cement improved frozen soil after thawing compression[J]. Hydrogeology & Engineering Geology,2021,48(2):97 − 105. (in Chinese with English abstract)
[24] 胡冉, 陈益峰, 周创兵. 基于孔隙分布的变形土土水特征曲线模型[J]. 岩土工程学报,2013,35(8):1451 − 1462. [HU Ran, CHEN Yifeng, ZHOU Chuangbing. A water retention curve model for deformable soils based on pore size distribution[J]. Chinese Journal of Geotechnical Engineering,2013,35(8):1451 − 1462. (in Chinese with English abstract)
[25] 李同录, 张辉, 李萍, 等. 不同沉积环境下马兰黄土孔隙分布与土水特征的模式分析[J]. 水文地质工程地质,2020,47(3):107 − 114. [LI Tonglu, ZHANG Hui, LI Ping, et al. Mode analysis of pore distribution and soil-water characteristic curve of Malan loess under different depositional environments[J]. Hydrogeology & Engineering Geology,2020,47(3):107 − 114. (in Chinese with English abstract)
[26] DAVID SUITS L, SHEAHAN T C, LEONG E C, et al. Factors affecting the filter paper method for total and matric suction measurements[J]. Geotechnical Testing Journal,2002,25(3):8198. doi: 10.1520/GTJ11094J
[27] LEONG E C. Soil-water characteristic curves - Determination, estimation and application[J]. Japanese Geotechnical Society Special Publication,2019,7(2):21 − 30. doi: 10.3208/jgssp.v07.003
[28] KOYLUOGLU U. Soil mechanics for unsaturated soils[J]. Soil Dynamics and Earthquake Engineering,1993,12(7):449 − 450.
[29] GAO Y, SUN D A, ZHOU A N, et al. Predicting shear strength of unsaturated soils over wide suction range[J]. International Journal of Geomechanics,2020,20(2):04019175. doi: 10.1061/(ASCE)GM.1943-5622.0001555
[30] KRISTO C, RAHARDJO H, SATYANAGA A. Effect of variations in rainfall intensity on slope stability in Singapore[J]. International Soil and Water Conservation Research,2017,5(4):258 − 264. doi: 10.1016/j.iswcr.2017.07.001
[31] MYERS D E. Reliability and statistics in geotechnical engineering[J]. Technometrics,2005,47(1):103 − 104. doi: 10.1198/tech.2005.s838
[32] PHOON K K. Reliability-based design in geotechnical engineering: Computations and applications[M]. Boca Raton: CRC Press, 2008.
[33] XIAO Z P, LÜ Q, ZHENG J, et al. Conditional probability-based system reliability analysis for geotechnical problems[J]. Computers and Geotechnics, 2020, 126: 103751.
[34] WANG Q, FANG H B. An adaptive high-dimensional model representation method for reliability analysis of geotechnical engineering problems[J]. International Journal for Numerical and Analytical Methods in Geomechanics, 2020, 44(12): 1705 − 1723.
[35] NEMES A, SCHAAP M G, LEIJ F J, et al. Description of the unsaturated soil hydraulic database UNSODA version 2.0[J]. Journal of Hydrology, 2001, 251(3/4): 151−162.
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