# Experimental Study on Shear Creep Characteristics of Residual Soil with Different Stone Content
## 1 Introduction  
Creep landslide refers to the type of landslide with continuous, slow, and long-term deformation. The creep properties of landslide materials are often the primary reason for failure and instability in such cases [1; 2; 3; 4; 5]. Therefore, analyzing the creep properties of landslide materials serves as a crucial theoretical foundation for studying the deformation mechanism and conducting stability analyses of creep landslides. The study of creep properties of landslide materials primarily involves creep tests, constitutive models, and long-term strength [6; 7; 8; 9]. Previous research on creep landslides mainly concentrated on homogeneous soils such as loess, clay, sandy clay, and silty clay, as well as soft rocks. The creep process typically encompasses three stages: initial creep, steady-state creep, and accelerated creep. In cases where the stress exerted on the rock or soil surpasses its long-term strength, accelerated creep occurs, leading to significant sliding damage [10; 11; 12; 13; 14]. The development of a constitutive model that effectively captures the rheological properties of rock and soil based on an analysis of their rheological characteristics is a key focus in the field of rheological mechanics research [15; 16; 17]. Extensive research has been conducted by scholars globally on rheological models, with the component model, particularly the Burgers model, being widely utilized for describing the creep behavior of different rock and soil formations [18; 19]. The Burgers model is favored due to its intuitive concept, parameters with clear physical meaning, and straightforward calculations [20]. Residual soil is the sediment that slowly moves downhill after undergoing natural weathering and eventually deposits on gentle slopes. Under the action of gravity, the residual soil exhibits slowly over an extended period, leading to the formation of a creep landslide. These landslides can cause wide-ranging, large-scale, and long-term damage. Currently, due to the limitations of instruments and equipment, there is limited research on the creep behavior of geotechnical bodies with particle sizes larger than 2 mm [21; 22; 23], and there is a lack of studies on the creep characteristics of residual soil containing large particles. [PERSON] et al. carried out a triaxial creep test of Majiagou landslide in the Three Gorges Reservoir area. The study showed that the coarse-grained soil exhibited evident nonlinear creep characteristics, with the surrounding pressure and stress levels having a significant impact on the creep rate and stage division. The Singh-Mitchell creep model was used to describe the creep behavior of coarse-grained soil [24]. [PERSON] et al. conducted a direct shear creep test on a landslide deposit, revealing decelerated creep and steady-state creep characteristics. The deposit would transition into an accelerated creep state when subjected to a larger horizontal load, and the long-term strength of the deposit was found to be between 39% and 59% of its instantaneous shear strength [25]. In another investigation, [PERSON] et al. performed a large-scale triaxial creep test on a strongly weathered muddy sandstone slide zone. They found that the adjustment of the internal structure of the specimen at lower stress levels is primarily governed by void compression and particle movement, and particle fragmentation was observed mainly at higher stress levels [26]. Additionally, [PERSON] et al. conducted a study on two groups of landslide soils with different stone contents. They found that a significant increase in creep stresses led to specimen failure and the ratio of creep stresses to residual strengths as the stone content increased [27]. The residual soil in mountainous regions exhibits wide distribution, poor structural properties, and varying stone content. The stone content plays a crucial role in their creep properties. This study focuses on a creep landslide involving residual soil in western Henan Province.