压缩条件下非饱和黄土的结构流体等效应力特性

 对不同含水率的西安原状、重塑及人工结构性黄土进行压缩试验，依据变形等效原则，用同一固结孔隙比下非饱和黄土与相同干密度饱和黄土的应力之差确定结构流体等效应力，探讨结构流体等效应力的特性。分析结果表明：西安原状、重塑及人工结构性黄土的结构流体等效应力与总应力及饱和度之间呈幂函数关系，这与其他地区原状黄土定性上相同，结构流体等效应力的变化规律具有很强的普适性。结构流体等效应力能够反映黄土的结构性、湿度及应力的变化，其幂函数表达式中参数与含水率、结构性、干密度有关。根据此幂函数关系式可以确定湿载耦合作用下非饱和黄土的结构流体等效应力，进而得到非饱和黄土的有效应力及有效应力压缩曲线。

CHARACTERISTICS OF EQUIVALENT STRESS OF STRUCTURAL FLUID OF UNSATURATED LOESS UNDER COMPRESSION

The compression tests are conducted on Xi?an intact and remoulded as well as artificially structural loesses under different moisture contents. Based on the principle of equivalent deformation，the equivalent stress of structural fluid is ascertained by using compressive stress difference between unsaturated and saturated loesses which have the same dry density and consolidation void ratio. The characteristics of equivalent stress of structural fluid are investigated. The research result indicates that the relationship between equivalent stress of structural fluid and stress as well as degree of saturation on Xi?an intact and remoulded as well as artificially structural loesses is power function，which is the same as that on the loess of other regions qualitatively. The variation regularity of equivalent stress of structural fluid is successfully universal. The changes of structural property and moisture content of loess as well as stress can be reflected by the equivalent stress of structural fluid；and the parameters of power function equation of equivalent stress of structural fluid are relative to moisture content and structural property as well as dry density. The equivalent stress of structural fluid under the condition of coupling of stress and moisture is calculated by the power function equation. Furthermore，effective stress and the compression curves of effective stress of unsaturated loess can be obtained.