# Study on the Development Rule of Mudstone Cracks in Open-Pit Mine Dumps Improved with Xanthan Gum
## 1 Introduction  
In geotechnical engineering, the stability analysis of slopes is a crucial research topic, especially in areas prone to landslides. Given the frequent landslide occurrences in China, the stability issue of open-pit mine slopes is particularly prominent [1, 2]. Compared to conventional rock slopes, the waste dump slopes of open-pit mines are loose body slopes formed by the accumulation of topsoil and rocks stripped during the mining process. These include different grain sizes and types of soil and rock masses, making their mechanical properties more complex. At the same time, the stability of waste dump slopes is influenced by geological conditions and natural factors such as rainfall [3], earthquakes, typhoons, and other extreme weather conditions that can lead to landslide disasters. Surface shrinkage and cracking on waste dump slopes are extremely common. Under rainfall and wet-dry cycles, small cracks can develop into large fissures or gullies, significantly increasing the risk of landslides on waste dump slopes [4, 5]. Therefore, studying the laws of shrinkage and cracking of open-pit mine waste dumps and taking corresponding measures is significant for the safety of open-pit mine production. The human-induced slow construction of open-pit mine waste dumps provides the feasibility of improving their properties by adding specific materials. In the field of geotechnical engineering, modified materials are being widely applied to enhance engineering performance and efficiency. These materials include microbially modified materials [6],nanomaterials [7], and reinforced materials [8], among others. Currently, some materials and technologies at home and abroad can suppress the cracking of soil and rock masses. By incorporating natural fibers [9] (e.g., lignocellulose, bagasse, and plant roots), adding natural gels [10; 11] (guar and xanthan gums, etc. ), spraying soil consolidating solutions [12; 13] (MICP, EICP, etc. ), and biochar chemical treatment [14], the solidification of soil and rock masses can be effectively achieved, realizing the effect of inhibiting the shrinkage and cracking of the surface of soil and rock masses. [PERSON] et al. [15] enhanced the erosion resistance and water retention of waste dumps by spreading PAM powder particles and spraying PAM consolidating solutions. The results of indoor experiments showed that this treatment method can significantly improve the erosion resistance of the slope surface under rainfall conditions and reduce porosity, effectively reducing soil and water loss. [PERSON] et al. [16] evaluated the impact of MICP technology on inhibiting the drying cracks of clay through a series of field experiments. The CaCO\({}_{3}\) crystals produced by the MICP process effectively inhibited the generation of soil and rock cracks by filling the crack space, consolidating soil particles, and reducing soil moisture evaporation. [PERSON] et al. [17] explored the impact of different amounts of xanthan gum and sand content on the crack resistance of surface soil to suppress the development of cracks caused by surface drying. The results showed that combining xanthan gum biopolymers and a certain amount of sand can effectively increase the cohesion within the soil and enhance the crack resistance. [PERSON] et al. [18] found that adding xanthan gum provided good anti-seepage properties to the clay layer and significantly reduced the macroscopic crack rate when studying the impermeability function of biopolymers in clay layers. Although there are many studies on the modification of soil and rock masses, most of them focus on improving the macroscopic mechanical properties of soil and rock masses, and there are fewer studies on the modification of complex soil and rock mixtures such as open-pit mine waste dumps. The effects and mechanisms of modification are still unclear. This study selects the environmentally friendly xanthan gum biopolymer as a modifying material widely used in geotechnical modification.