摘要
【目的】土—水特征曲线是非饱和红黏土的重要概念,从结构性出发分析红黏土的土—水特征曲线对实际工程具有重要意义。【方法】采用离心机对初始状态相同的原状和重塑红黏土进行宏观土—水特征曲线试验,获得原状和重塑红黏土的土—水特征曲线,并通过电镜扫描试验,观察原状和重塑红黏土的微观结构特征,分析结构性对红黏土土—水特征曲线的影响。【结果】试验结果表明,原状和重塑红黏土的基质吸力随着体积含水率的减小而增加,体积含水率相同的情况下,原状土的基质吸力较大;原状土的原生结构没有破坏,骨架稳定,孔隙较小,重塑土骨架遭到破坏,孔隙较大且分布均匀,因此原状土失水速率较慢,持水能力较强,进气值较大。【结论】研究结果揭示了结构性影响红黏土土—水特征曲线的内在机理,可为解决实际工程问题提供理论支持。
[Purposes]The soil—water characteristic curve is an important concept of unsaturated red clay,and it is of great significance to analyze the soil—water characteristic curve of red clay from the structural point of view.[Methods]The macroscopic soil—water characteristic curves of the undisturbed and remodeled red clay with the same initial state were tested by centrifuge,and the soil—water charac-teristic curves of the undisturbed and remodeled red clay were obtained,and the microstructure charac-teristics of the undisturbed and remodeled red clay were observed by electron microscope scanning test,and the influence of structure on the soil—water characteristic curve of red clay was discussed from the macro and micro perspectives.[Findings]The test results show that the matrix suction of undisturbed and remodeled red clay increases with the decrease of volumetric moisture content,and the matrix suc-tion of undisturbed soil is larger when the volumetric moisture content is the same.The original structure of the undisturbed soil is not damaged,the skeleton is stable,the pores are small,the skeleton of the re-shaped soil is damaged,and the pores are large and evenly distributed,so the water loss rate of the undis-turbed soil is slow,the water—holding capacity is strong,and the air intake value is larger.[Conclu-sions]The results reveal the internal mechanism of structural influence on the soil—water characteristic curve of red clay,which can provide theoretical support for solving practical engineering problems.
作者
李久鹏
张亚彬
LI Jiupeng;ZHANG Yabin(Henan Provincial Communications Planning,Design Institute Co.,Ltd.,Zhengzhou 450000,China)
出处
《河南科技》
2024年第14期68-71,共4页
Henan Science and Technology
关键词
红黏土
结构性
土—水特征曲线
电镜扫描
red clay
structural
soil—water characteristic curve
electron microscope scan
