不同干密度下土水特征曲线模型参数确定简化方法
|
摘要
为避免获得土水特征曲线模型参数的复杂测试过程,提出了一种确定模型参数的简化方法。通过使用Gardner,Van Genuchten,Fredlund&Xing 3种模型对土水特征曲线数据拟合,发现3种模型相关系数除干密度为1.50,1.60,1.71 g/cm~3时Gardner模型的决定系数R~2为0.940,0.949,0.953,其他相关系数均超过了0.96,拟合效果较好。对Gardner模型和Van Genuchten模型中各参数进行分析,发现它们与干密度之间有良好的相关性,干密度和各模型参数之间成线性、二次函数和幂函数关系,并据此提出了由干密度确定模型参数的简化方法,具有一定的实用性,期望能为工程提供参考。
Soil-water characteristic curve(SWCC) was fitted by Gardner's model, Van Genuchten's model, and Fredlund & Xing's model to find that in addition to the correlation coefficient R~2(0.940, 0.949, 0.953) fitted by Gardner's model when dry density equals 1.5 g/cm~3, 1.6 g/cm~3, and 1.71 g/cm~3, the correlation coefficients fitted by other models all exceed 0.96, indicating a good fitting effect. The parameters in Gardner's model and Van Genuchten's are of good correlation with dry density. On this basis, a simplified method for determining the model parameters according to dry density is proposed to avoid the complex testing process for obtaining the model parameters. The proposed method is practical and is expected to offer reference for engineering.
Soil-water characteristic curve(SWCC) was fitted by Gardner's model, Van Genuchten's model, and Fredlund & Xing's model to find that in addition to the correlation coefficient R~2(0.940, 0.949, 0.953) fitted by Gardner's model when dry density equals 1.5 g/cm~3, 1.6 g/cm~3, and 1.71 g/cm~3, the correlation coefficients fitted by other models all exceed 0.96, indicating a good fitting effect. The parameters in Gardner's model and Van Genuchten's are of good correlation with dry density. On this basis, a simplified method for determining the model parameters according to dry density is proposed to avoid the complex testing process for obtaining the model parameters. The proposed method is practical and is expected to offer reference for engineering.
引文
[1] 丁少林,左昌群,刘代国,等.非饱和残积土土-水特性研究及基质吸力估算[J].长江科学院院报,2016,33(3):98-103.
[2] 王晓峰,时红莲,王震,等.非饱和土渗透系数曲线的分段简化模型[J].长江科学院院报,2015,32(2):72-77.
[3] 常波,吴益平,何高峰,等.临江Ⅱ号崩滑体土水特征曲线试验研究[J].长江科学院院报,2012,29(9):53-58.
[4] VANAPALLI S K, FREDLUND D G, PUFAHL D E. Relationship Between Soil-water Characteristic Curves and the As-compacted Water Content versus Soil for a Clay Till[C]//Proceedings of Ⅺ Pan-American Conference on Soil Mechanics and Foundation Engineering. Brazil: Iguanzu Falls, August 8-13, 1999: 991-998.
[5] 褚峰,邵生俊,陈存礼.干密度和竖向应力对原状非饱和黄土土水特征影响的试验研究[J].岩石力学与工程学报,2014, 33(2):413-420.
[6] 张雪东,赵成刚,刘艳,等.变形对土水特征曲线影响规律模拟研究[J].土木工程学报,2011,44(7):119-126.
[7] 陶高梁,孔令伟,肖衡林,等.土-水特征曲线的分形特性及其分析拟合[J].岩土力学,2014,35(9):2443-2447.
[8] GARDNER W R. Some Steady-state Solutions of the Unsaturated Moisture Flow Equation with Application to Evaporation from a Water Table[J]. Soil Science, 1958, 85(4):228-232.
[9] 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.
[10] FREDLUND D G, XING A. Equations for the Soil-water Characteristic Curve[J]. Canadian Geotechnical Journal, 1994, 31(4): 521-532.
[11] FREDLUND D G. Unsaturated Soil Mechanics in Engineering Practice[M]. New Jersey: John Wiley & Sons, 2012.
[12] 刘奉银,张昭,周冬,等.密度和干湿循环对黄土土-水特征曲线的影响[J].岩土力学,2011,32(增2):132-136.
[2] 王晓峰,时红莲,王震,等.非饱和土渗透系数曲线的分段简化模型[J].长江科学院院报,2015,32(2):72-77.
[3] 常波,吴益平,何高峰,等.临江Ⅱ号崩滑体土水特征曲线试验研究[J].长江科学院院报,2012,29(9):53-58.
[4] VANAPALLI S K, FREDLUND D G, PUFAHL D E. Relationship Between Soil-water Characteristic Curves and the As-compacted Water Content versus Soil for a Clay Till[C]//Proceedings of Ⅺ Pan-American Conference on Soil Mechanics and Foundation Engineering. Brazil: Iguanzu Falls, August 8-13, 1999: 991-998.
[5] 褚峰,邵生俊,陈存礼.干密度和竖向应力对原状非饱和黄土土水特征影响的试验研究[J].岩石力学与工程学报,2014, 33(2):413-420.
[6] 张雪东,赵成刚,刘艳,等.变形对土水特征曲线影响规律模拟研究[J].土木工程学报,2011,44(7):119-126.
[7] 陶高梁,孔令伟,肖衡林,等.土-水特征曲线的分形特性及其分析拟合[J].岩土力学,2014,35(9):2443-2447.
[8] GARDNER W R. Some Steady-state Solutions of the Unsaturated Moisture Flow Equation with Application to Evaporation from a Water Table[J]. Soil Science, 1958, 85(4):228-232.
[9] 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.
[10] FREDLUND D G, XING A. Equations for the Soil-water Characteristic Curve[J]. Canadian Geotechnical Journal, 1994, 31(4): 521-532.
[11] FREDLUND D G. Unsaturated Soil Mechanics in Engineering Practice[M]. New Jersey: John Wiley & Sons, 2012.
[12] 刘奉银,张昭,周冬,等.密度和干湿循环对黄土土-水特征曲线的影响[J].岩土力学,2011,32(增2):132-136.
© 2004-2018 中国地质图书馆版权所有 京ICP备05064691号 京公网安备11010802017129号 地址：北京市海淀区学院路29号 邮编：100083 电话：办公室：(+86 10)66554848；文献借阅、咨询服务、科技查新：66554700 |