基于强度条件的黄土结构性静力试验研究

Test study of loess structure based on static strength conditions

土体的结构是其强度、变形的内在决定因素,黄土的结构性由黄土颗粒之间的联结结构强度和摩擦结构强度所决定。由此,提出了基于强度条件的黄土静力结构性参数即联结结构静力强度势参数m1ε、摩擦结构静力强度势参数mε2以及结构静力强度势参数mε,并通过黄土的三轴试验研究了原状黄土和人工水泥结构性黄土的结构性及基于强度条件的黄土静力结构性参数的变化规律,揭示了含水率、围压、轴向变形对原状黄土和水泥人工结构性黄土结构性的影响。结果表明,原状黄土的含水率越小,其结构性越强,结构破坏后土体强度损失越大;黄土结构的损伤破坏主要发生在小应变阶段。并对所提出的基于强度条件的黄土静力结构性参数的合理性进行了讨论。

Soil structure is the intrinsic determinants of its strength and deformation.Loess structure is determined by the link structural strength and the friction structural strength.Based on this,some new and reasonable structural parameters of loess are suggested based on soil static strength,such as the link structural static strength potential parameters,the friction structural static strength potential parameters and the structural static strength potential parameters.The variation of the structure and the structural parameters based on the static strength conditions are studied with the triaxial compression tests of intact loess and artificial cement structural loess;and the impacts of moisture content,confining pressure and axial deformation on the structure of intact loess and artificial cement structural loess are revealed.The results show that the water content of loess is smaller;its structure is stronger;and the greater loss of soil mass strength will occur after the structural damage.Loess structure damage mainly occurs in the small strain stage.Finally,the rationality of these structural parameters based on the static strength conditions are discussed.