Research on the structural parameters of loess based on shear strength

Based on the concept of comprehensive structural potential, many scholars have currently defined various structural parameters of loess. However, these parameters are mostly defined based on the deformation characteristics of soil samples. Due to the significant influence of the calculation process by experimental conditions and stress-strain states, these parameters are difficult to accurately represent the intrinsic relationship between the structural characteristics of loess and its mechanical strength. This problem has become a key bottleneck restricting the deepening of loess structural research. Therefore, this paper takes the shear strength theory as the core support and proposes a structural parameter of loess based on complex stress states. This parameter not only can directly reflect the coupling relationship between the structural characteristics and mechanical strength of loess, but also has the advantage of adapting to complex stress environments. More importantly, its calculation results are independent of specific stress states and experimental conditions, and have stronger universality. Based on the results of the three-axis shear test, this paper systematically analyzed the variation patterns of the shear strength and new structural parameters of loess samples under different moisture contents and dry densities; by deeply exploring the correlation mechanism between the shear strength of loess and its structure, the rationality and stability of this complex stress-type structural parameter were further verified. This study provides more reliable parameter indicators for the evaluation of loess structure, and also offers a new research perspective for revealing the structural control mechanism of loess mechanical behavior.