土壤含水率与土壤碱度对土壤抗剪强度的影响  

Effects of soil water content and soil sodicity on soil shearing strength

作　　者：陈红星[1] 李法虎[1] 郝仕玲[1] 张心平[1] 

机构地区：[1]中国农业大学水利与土木工程学院,北京100083

出　　处：《农业工程学报》2007年第2期21-25,共5页Transactions of the Chinese Society of Agricultural Engineering

基　　金：农业部农业生态环境科技项目;中国农业大学精品课程建设项目

摘　　要：土壤含水率和土壤碱度是表征土壤物理化学性质的两个重要参数。通过室内三轴不固结不排水试验,研究了土壤含水率和土壤碱度对土壤抗剪强度的影响。试验处理采用5种土壤碱度(土壤可交换钠百分比ESP=0、5、10、20、40)和4种土壤质量含水率(0.05、0.10、0.20以及饱和含水率0.34)水平。试验结果显示,土壤黏聚力随着土壤含水率的增加基本上呈先增大后减小之趋势;当土壤含水率在0.10附近时黏聚力达到其最大值。土壤内摩擦角随着土壤含水率的增加而线性减小。土壤碱度对土壤黏聚力的影响机理较为复杂,其影响效果随土壤含水率的增加而减小;但土壤碱度对土壤内摩擦角的影响较小。土壤碱度对土壤抗剪强度的影响程度明显地小于土壤含水率对其的影响程度。Soil water content and soil sodicity are two important parameters of soil physical and chemical characteristics. Effects of soil water content and soil sodicity on soil shearing strength were carried out in laboratory by triaxial shearing test under unconsolidated-undrained conditions. Five soil exchangeable sodium percentages （ESP） of 0, 5, 10, 20, 40 and four soil water contents（w/w） of 0.05, 0. 10, 0.20, 0.34（saturated） were tested. Experimental data indicate that soil cohesive force firstly increases and then decreases with the increase of soil water content, and it reaches to the maximum at the water content of about 0.10. Soil internal frictional angle decreases linearly with the increase of soil water content. The influence mechanism of soil ESP on soil cohesive force is complicated and its effect decreases with the increase of soil water content. The soil ESP influence on soil internal frictional angle is small. The effect of soil water content on soil shearing strength is much greater than that of soil sodicity.

关 键 词：土壤含水率 土壤碱度 土壤抗剪强度 抗剪强度指标 

分 类 号：S152.7[农业科学—土壤学] TU432[农业科学—农业基础科学]