土壤液限和抗剪强度特征值及其影响因素研究——基于紫色土区  

Characters and Effects of Soil Liquid Limit and Shear Strength in Purple Hilly-mountainous Region

作　　者：花可可[1,2] 魏朝富[1,2] 任镇江[1,2] 

机构地区：[1]西南大学三峡库区生态环境教育部重点实验室,重庆400715 [2]西南大学资源环境学院,重庆400715

出　　处：《农机化研究》2011年第6期105-110,共6页Journal of Agricultural Mechanization Research

基　　金：国家科技支撑计划项目(2008BAD98B02);西南大学生态学重点学科"211工程"项目(2005-2010)

摘　　要：紫色土区土壤力学性质独特,造成土壤侵蚀现象严重,对水土保持和农田基本建设产生了较大的影响。为此,以紫色土和水稻土两种代表性土壤为例,通过液塑限联合测定试验和快速剪切试验,测定土壤的液限及抗剪强度特征值,并对其影响因素进行探讨。结果表明：紫色土和水稻土两种土壤的液限值差异较大;紫色土的液限值为13.37%~15.75%,平均值为14.42%,水稻土液限值为42.61%~47.64%,平均值为45.16%;紫色土为一般性粘土,而水稻土为高液限粘性土。粘粒和有机质是影响土壤液限值的重要因素,且土壤液限受有机质影响最为强烈,三者之间符合多元线性回归分析方程,相应的VAF和RMSE值分别为92.18,96.86和0.19,0.24,R2值分别为0.922和0.969。在100kPa固定压力下,紫色土和水稻土的抗剪强度差异明显,水平值分别为61.91kPa和46.76kPa,水稻土的抗剪强度小于紫色土,且土壤液性指数与抗剪强度之间具有明显的指数函数关系。Purple soil due to be intensity soil erosion and special mechanics has a great influence in water preservation and construction of farmland.In this study,purple and paddy soils were tested through liquid and plastic limit and direct shear box test to acquit the value of liquid and plastic and shear strength.The results showed that the diversity of two kinds of soils was so obvious.The liquid limit of purple soil was between 13.37 percent and 15.75 percent and the average was 14.42 percent.However,the paddy soil was between 42.67 percent and 47.64 percent and average was 45.16 percent.So it was concluded that purple soil was a common soil while paddy soil was a high liquid soil.Clay and organic matter were the most important factors influencing the liquid limit and organic matter mostly contributed to liquid limits.The relationship among them could be described through multi line regression analysis properly.VAF and RMSE were 92.18,96.86 and 0.19,0.24 respectively.The square R was 0.922 and 0.969.Under the fastness pressure 100kPa,the shear strength of purple and paddy soils was 61.91 and 46.76 kPa respectively.The paddy soil of shear strength was lower than purple＇s and the relationship between liquid index and shear strength could be described by exponential function.

关 键 词：紫色土 液塑限 抗剪强度 液性指数 

分 类 号：S15[农业科学—土壤学]