Stress–Strain Strength Characteristics of Undisturbed Granite Residual Soil Considering Different Patterns of Variation of Mean Effective Stress

Granite residual soil is one of the most frequently encountered problem soils in tropical regions, whose mechanical behavior heavily depends on pattern variation mean effective stress (p’) during shearing, which can be classified into three categories: increasing-p’, constant-p’, and decreasing-p’. Unfortunately, so far, stress–strain strength characteristics granite have been studied mainly under increasing-p’ paths, although it very likely to encounter paths with decreasing p’ practice, especially excavation engineering. Moreover, pertinent research has focused remolded soils, whereas undisturbed specimens not yet received enough attention. In this paper, path triaxial tests considering different patterns were conducted an soil. Subsequently, a variable termed loading angle was introduced quantitatively represent path. The influences Mohr–Coulomb parameters, deformation characteristics, ductility, shearing stiffness analyzed, emphasis role stress. experimental results show that friction increases while cohesion decreases increase angle. leads less volume contraction smaller failure strain. During exhibited brittle response angles. initial secant shear modulus first decreased then increased as increased, minimum occurring at certain lying between 90° 123.7°.