初始干密度对非饱和土变形及强度影响的试验研究  

INFLUENCE OF DIFFERENT INITIAL DRY DENSITY ON DEFORMATION AND STRENGTH OF UNSATURATED SOIL

作　　者：庄心善[1] 彭伟珂 吴镜泊 

机构地区：[1]湖北工业大学土木建筑与环境学院,武汉430068

出　　处：《工业建筑》2017年第3期107-110,181,共5页Industrial Construction

基　　金：国家自然科学基金项目(51209084)

摘　　要：通过压力板仪测定并对比分析了不同初始干密度下粉质黏土的土水特征曲线;使用GDS非饱和土三轴仪,进行了不同初始干密度、不同基质吸力下非饱和粉质黏土的强度试验。结果表明:van Genuchten模型可以较好拟合不同初始干密度粉质黏土土水特征曲线;试样进气值与初始干密度呈正相关,持水能力和水稳定性随初始干密度的增大逐渐增大;相同初始干密度的非饱和粉质黏土强度随基质吸力的增大而增大,随着基质吸力的增大,基质吸力对试样抗剪强度的贡献值逐渐变小。不同初始干密度的试样体积变化均随着基质吸力的增大而减小,且初始干密度越大,不同基质吸力试样体变越接近一致。重塑非饱和粉质黏土的应力-应变关系可以用双曲线模型来描述,试样切线模量随基质吸力的增大而增大。Through the pressure plate apparatus,the soil-water characteristic curves of silty clay under different initial dry densities were measured and compared. The strength test of unsaturated silty clay under different initial dry density and different matrix suction was carried out by using GDS unsaturated soil triaxial apparatus. The results showed that van Genuchten model could be used to fit the soil-water characteristic curve of different initial dry density silty clay well,the correlation coefficients were close to 1. 0. The intake values of the specimens positively correlated with the initial dry densities,and the water holding capacity and water stability increased with the increase of the initial dry densities. The strength of unsaturated silty clay with the same initial dry density increased with the increase of the matrix suction,and the contribution of matrix suction to the shear strength of the sample became smaller with the increase of the matrix suction. The volume change of specimens with different initial dry density decreased with the increase of the matrix suction,and the larger the initial dry density,the more closer to the same. The stress-strain relationship of the unsaturated silty clay could be described by a hyperbolic model,and the tangent modulus of the specimens increased with the increase of the matrix suctions.

关 键 词：初始干密度 土水特征曲线 GDS三轴仪 应力-应变关系 非饱和土 

分 类 号：TU411[建筑科学—岩土工程]