基于土壤转换函数(PTF)预测不同初始孔隙比土的土–水特征曲线
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摘要
提出了预测van Genuchten(VG)模型参数n的一个土壤转换函数(pedotransfer function, PTF),该函数是一个非线性回归方程,结合VG模型参数?与初始孔隙比e0的回归方程,来预测不同初始孔隙比土的土–水特征曲线(SWCC)。n和?回归方程中的拟合参数(a,b和A,B)只需通过3组常规的SWCC试验数据即可校正。将选取的具有代表性的各个文献中的试验数据均分成两部分:一部分用于校正拟合参数(a,b和A,B),另一部分用于验证基于PTF预测SWCC方法的准确性。结果表明,基于PTF所预测得SWCC与文献中的试验数据具有很好的一致性。PTF只需引入一个预测变量即初始孔隙比e0;它不仅适用于变形土,也适用于非变形土。
A pedotransfer function(PTF), which is a nonlinear regression equation, is proposed for predicting the parameter n of the van Genuchten(VG) model. Considering the regressive relationship between the parameter ? of the VG model and the initial void ratio e0, the soil-water characteristic curves(SWCCs) of soil specimens with different initial void ratios can be accurately predicted. The fitting parameters(i.e., a, b and A, B) of the regression equations corresponding to the parameters n and ? can be calibrated using the test data obtained from three sets of conventional SWCC tests. The test data in each reference available are divided into two parts. One part is used for the calibration of the fitting parameters(i.e., a, b and A, B), and the other part is employed for the verification of the predicted SWCCs based on PTFs. The results show that the SWCCs, which are predicted by using the proposed nonlinear regression equation(PTF) concerning the parameter n of the VG model, have good agreement with the test data in the references. Only one predictive variable(i.e., initial void ratio, e0) is needed in the proposed PTF. This PTF is suitable for both rigid and deformable soils.
A pedotransfer function(PTF), which is a nonlinear regression equation, is proposed for predicting the parameter n of the van Genuchten(VG) model. Considering the regressive relationship between the parameter ? of the VG model and the initial void ratio e0, the soil-water characteristic curves(SWCCs) of soil specimens with different initial void ratios can be accurately predicted. The fitting parameters(i.e., a, b and A, B) of the regression equations corresponding to the parameters n and ? can be calibrated using the test data obtained from three sets of conventional SWCC tests. The test data in each reference available are divided into two parts. One part is used for the calibration of the fitting parameters(i.e., a, b and A, B), and the other part is employed for the verification of the predicted SWCCs based on PTFs. The results show that the SWCCs, which are predicted by using the proposed nonlinear regression equation(PTF) concerning the parameter n of the VG model, have good agreement with the test data in the references. Only one predictive variable(i.e., initial void ratio, e0) is needed in the proposed PTF. This PTF is suitable for both rigid and deformable soils.
引文
[1]陈正汉.非饱和土与特殊土力学的基本理论研究[J].岩土工程学报,2014,36(2):201-272.(CHEN Zheng-han.On basic theories of unsaturated soils and special soils[J].Chinese Journal of Geotechnical Engineering,2014,36(2):201-272.(in Chinese))
[2]施建勇,赵义.气体压力和孔隙对垃圾土体气体渗透系数影响的研究[J].岩土工程学报,2015,37(4):586-593.(SHI Jian-yong,ZHAO Yi.Influence of air pressure and void on permeability coefficient of air in municipal solid waste(MSW)[J].Chinese Journal of Geotechnical Engineering,2015,37(4):586-593.(in Chinese))
[3]孙德安,高游,刘文捷,等.红黏土的土水特性及其孔隙分布[J].岩土工程学报,2015,37(2):351-356.(SUNDe-an,GAO You,LIU Wen-jie,et al.Soil-water characteristics and pore-size distribution of lateritic clay[J].Chinese Journal of Geotechnical Engineering,2015,37(2):351-356.(in Chinese))
[4]吴宏伟.大气-植被-土体相互作用:理论与机理[J].岩土工程学报,2017,39(1):1-47.(CHARLES Wang-Wai Ng.Atmosphere-plant-soil interactions:theories and mechanisms[J].Chinese Journal of Geotechnical Engineering,2017,39(1):1-47.(in Chinese))
[5]孔令伟,陈建斌,郭爱国,等.大气作用下膨胀土边坡的现场响应试验研究[J].岩土工程学报,2007,29(7):1065-1073.(KONG Ling-wei,CHEN Jian-bin,GUO Ai-guo,et al.Artificial rainfall infiltration tests on a well-instrumented unsaturated expansive soil slope[J].Chinese Journal of Geotechnical Engineering,2007,29(7):1065-1073.(in Chinese))
[6]谢妮,邹维列,严秋荣,等.黄土路基边坡降雨响应的试验研究[J].四川大学学报(工程科学版),2009,41(4):31-36.(XIE Ni,ZOU Wei-lie,YAN Qiu-rong,et al.Experimental research on response of a loess subgrade slope to artificial rainfall[J].Journal of Sichuan University(Engineering Science Edition),2009,41(4):31-36.(in Chinese))
[7]赵成刚,韦昌富,蔡国庆.土力学理论的发展和面临的挑战[J].岩土力学,2011,32(12):3521-3540.(ZHAOCheng-gang,WEI Chang-fu,CAI Guo-qing.Development and challenge for soil mechanics[J].Rock and Soil Mechanics,2011,32(12):3521-3540.(in Chinese))
[8]VAN Genuchten M T.A closed-form equation for predicting the hydraulic conductivity of unsaturated soil[J].Soil Science Society American Journal,1980,44:892-898.
[9]MINASNY B,MCBRATNEY A B,BRISTOW K L.Comparison of different approaches to the development of pedotransfer functions for water-retention curves[J].Geoderma,1999,93(3/4):225-253.
[10]TARANTINO A.A water retention model for deformable soils[J].Géotechnique,2009,59(9):751-762.
[11]W?STEN J H M,LILLY A,NEMES A,et al.Development and use of a database of hydraulic properties of europeansoils[J].Geoderma,1999,90(3/4):169-185.
[12]HODNETT M G,TOMASELLA J.Marked differences between van Genuchten soil water-retention parameters for temperate and tropical soils:a new water-retention pedo-transfer functions developed for tropical soils[J].Geoderma,2002,108(3/4):155-180.
[13]RAJKAI K,KABOS S,GENUCHTEN M T V.Estimating the water retention curve from soil properties:comp-arison of linear,nonlinear and concomitant variable methods[J].Soil&Tillage Research,2004,79(2):145-152.
[14]MATULA S.Pedotransfer function application for estimation of soil hydrophysical properties using parametric methods[J].Plant Soil&Environment,2007,53(4):149-157.
[15]TIRZAH M D M,CORREA P O.Artificial neural networks for estimating soil water retention curve using fitted and measured data[J].Applied&Environmental Soil Science,2015:1-16.
[16]EBRAHIM-ZADEH G,BAYAT H,SINEGANI A A S,et al.Investigating the correlation between soil tensile strength curve and soil water retention curve via modeling[J].Soil&Tillage Research,2017,167:9-29.
[17]ASSOULINE S.Modeling the relationship between soil bulk density and the water retention curve[J].Vadose Zone Journal,2006,5(2):554-563.
[18]AUBERTIN M,RICARD J F,CHAPUIS R P.A predictive model for the water retention curve:application to tailings from hard-rock mines[J].Canadian Geotechnical Journal,1998,35(35):55-69.
[19]LALIBERTE G E,COREY A T,BROOKS R H.Properties of unsaturated porous media[D].Fort Collins:Colorado State University,1966.
[20]VANAPALLI S K,PUFAHL D E,FREDLUND D G.The influence of soil structure and stress history on the soil-water characteristic of a compacted till[J].Géotechnique,1999,49(2):143-159.
[21]SUN W J,LIU S,SUN D,et al.Hydraulic and mechanical behavior of GMZ Ca-bentonite[J].Geotechnical Special Publication,Reston,VA,2014,236:125-134.
[22]HUANG S,FREDLUND D G,BARBOUR S L.Measurement of the coefficientof permeability for a deformable unsaturated soil using a triaxial permeameter[J].Canadian Geotechnical Journal,1998,35(3):426-432.
[23]STANGE C F,HORN R.Modeling the soil water retention curve for conditions of variable porosity[J].Vadose Zone Journal,2005,4(3):602-613.
[2]施建勇,赵义.气体压力和孔隙对垃圾土体气体渗透系数影响的研究[J].岩土工程学报,2015,37(4):586-593.(SHI Jian-yong,ZHAO Yi.Influence of air pressure and void on permeability coefficient of air in municipal solid waste(MSW)[J].Chinese Journal of Geotechnical Engineering,2015,37(4):586-593.(in Chinese))
[3]孙德安,高游,刘文捷,等.红黏土的土水特性及其孔隙分布[J].岩土工程学报,2015,37(2):351-356.(SUNDe-an,GAO You,LIU Wen-jie,et al.Soil-water characteristics and pore-size distribution of lateritic clay[J].Chinese Journal of Geotechnical Engineering,2015,37(2):351-356.(in Chinese))
[4]吴宏伟.大气-植被-土体相互作用:理论与机理[J].岩土工程学报,2017,39(1):1-47.(CHARLES Wang-Wai Ng.Atmosphere-plant-soil interactions:theories and mechanisms[J].Chinese Journal of Geotechnical Engineering,2017,39(1):1-47.(in Chinese))
[5]孔令伟,陈建斌,郭爱国,等.大气作用下膨胀土边坡的现场响应试验研究[J].岩土工程学报,2007,29(7):1065-1073.(KONG Ling-wei,CHEN Jian-bin,GUO Ai-guo,et al.Artificial rainfall infiltration tests on a well-instrumented unsaturated expansive soil slope[J].Chinese Journal of Geotechnical Engineering,2007,29(7):1065-1073.(in Chinese))
[6]谢妮,邹维列,严秋荣,等.黄土路基边坡降雨响应的试验研究[J].四川大学学报(工程科学版),2009,41(4):31-36.(XIE Ni,ZOU Wei-lie,YAN Qiu-rong,et al.Experimental research on response of a loess subgrade slope to artificial rainfall[J].Journal of Sichuan University(Engineering Science Edition),2009,41(4):31-36.(in Chinese))
[7]赵成刚,韦昌富,蔡国庆.土力学理论的发展和面临的挑战[J].岩土力学,2011,32(12):3521-3540.(ZHAOCheng-gang,WEI Chang-fu,CAI Guo-qing.Development and challenge for soil mechanics[J].Rock and Soil Mechanics,2011,32(12):3521-3540.(in Chinese))
[8]VAN Genuchten M T.A closed-form equation for predicting the hydraulic conductivity of unsaturated soil[J].Soil Science Society American Journal,1980,44:892-898.
[9]MINASNY B,MCBRATNEY A B,BRISTOW K L.Comparison of different approaches to the development of pedotransfer functions for water-retention curves[J].Geoderma,1999,93(3/4):225-253.
[10]TARANTINO A.A water retention model for deformable soils[J].Géotechnique,2009,59(9):751-762.
[11]W?STEN J H M,LILLY A,NEMES A,et al.Development and use of a database of hydraulic properties of europeansoils[J].Geoderma,1999,90(3/4):169-185.
[12]HODNETT M G,TOMASELLA J.Marked differences between van Genuchten soil water-retention parameters for temperate and tropical soils:a new water-retention pedo-transfer functions developed for tropical soils[J].Geoderma,2002,108(3/4):155-180.
[13]RAJKAI K,KABOS S,GENUCHTEN M T V.Estimating the water retention curve from soil properties:comp-arison of linear,nonlinear and concomitant variable methods[J].Soil&Tillage Research,2004,79(2):145-152.
[14]MATULA S.Pedotransfer function application for estimation of soil hydrophysical properties using parametric methods[J].Plant Soil&Environment,2007,53(4):149-157.
[15]TIRZAH M D M,CORREA P O.Artificial neural networks for estimating soil water retention curve using fitted and measured data[J].Applied&Environmental Soil Science,2015:1-16.
[16]EBRAHIM-ZADEH G,BAYAT H,SINEGANI A A S,et al.Investigating the correlation between soil tensile strength curve and soil water retention curve via modeling[J].Soil&Tillage Research,2017,167:9-29.
[17]ASSOULINE S.Modeling the relationship between soil bulk density and the water retention curve[J].Vadose Zone Journal,2006,5(2):554-563.
[18]AUBERTIN M,RICARD J F,CHAPUIS R P.A predictive model for the water retention curve:application to tailings from hard-rock mines[J].Canadian Geotechnical Journal,1998,35(35):55-69.
[19]LALIBERTE G E,COREY A T,BROOKS R H.Properties of unsaturated porous media[D].Fort Collins:Colorado State University,1966.
[20]VANAPALLI S K,PUFAHL D E,FREDLUND D G.The influence of soil structure and stress history on the soil-water characteristic of a compacted till[J].Géotechnique,1999,49(2):143-159.
[21]SUN W J,LIU S,SUN D,et al.Hydraulic and mechanical behavior of GMZ Ca-bentonite[J].Geotechnical Special Publication,Reston,VA,2014,236:125-134.
[22]HUANG S,FREDLUND D G,BARBOUR S L.Measurement of the coefficientof permeability for a deformable unsaturated soil using a triaxial permeameter[J].Canadian Geotechnical Journal,1998,35(3):426-432.
[23]STANGE C F,HORN R.Modeling the soil water retention curve for conditions of variable porosity[J].Vadose Zone Journal,2005,4(3):602-613.