Abstract: Accumulation landslides in western Hubei mountainous areas are widely distributed and large-scale, with deformation patterns closely related to the spatiotemporal characteristics of rainfall. 【Objective】To investigate the deformation behavior and evolutionary process of accumulation slopes in response to rainfall patterns, and to determine the sensitivity of landslide stability to various factors. 【Methods】This study examines the Landslide No. 1 in Machi Village, a typical accumulation landslide in Shiyan City, through physical model tests. The experiments simulate the landslide evolution process under four rainfall patterns: forward peak, central peak, uniform peak, and backward peak. Orthogonal testing and analysis of variance (ANOVA) are employed to identify the dominant factors influencing landslide stability. 【Results and Conclusion】The results indicate: (1) The influence of the four rainfall patterns on pore water pressure is primarily reflected in the timing of peak pressure, which occurs earlier when the rainfall peak is closer to the beginning. Moreover, backward peak rainfall leads to a relatively larger failure area and more pronounced disaster-inducing effects. (2) Under all rainfall patterns, slope deformation initiates in the middle section, starting with creep deformation, followed by step-like progressive failure until complete collapse. (3) ANOVA of orthogonal tests reveals that the sensitivity of factors affecting overall stability of the Landslide No. 1 in Machi Village, in descending order, is: internal friction angle (φ) > cohesion (c) > cumulative rainfall (T) > permeability coefficient (Ks) > unit weight of slip zone soil (γ) > rainfall pattern (Q). Cohesion (c) and internal friction angle (φ) are key shear strength parameters for evaluating landslide stability. (4) For local stability at the landslide front, permeability coefficient (Ks) is a critical factor, whereas cumulative rainfall (T) has a greater influence on overall stability.
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