# Study on Disintegration and Infiltration Characteristics of Nanjing Jiangxinzhou Embankment Soil
## 1 Introduction  
During the flood season, the water level of rivers, lakes, and seas increases under continuous heavy rainfall. It remains at a high level for a long time. An embankment has been in an aquatic environment for a long time, resulting in the deterioration of the embankment soil in many aspects. The instability of the embankment slope can cause significant losses to people's life security and property safety. In November 2017, a dangerous situation occurred near Guide Village, Sanmao Street, Yangzhong City, Zhenjiang City, Jiangsu Province, where the main river embankment collapsed about 240 m. In August 2020, during an inspection, the government of Luoshui Township, Shifang City, Deyang City, Sichuan Province, found a dangerous situation in the Zhonghekou section of Luoshui Township, Shiting River. By the flood, the overall collapse of the embankment was more than 250 m, causing economic losses of more than CNY 4,000,000. The study of soil hydrophysical properties (including water-holding, water-stability, and permeability) is of great significance to the study of mechanical stability, consolidationdeformation, and structural evolution of soils so that the knowledge of the above hydrophised properties will help to understand the intrinsic mechanisms of soils generating engineering diseases more systematically. Rainfall and immersion can rapidly transition from unsaturated to saturated soils submerged by wetting fronts. The volume of a liquid phase in the pore space increases, the solid phase components, such as crystalline and soluble salt, dissolve and transport, and the gas phase components decrease in volume due to extrusion or escape to the atmosphere, leading to slope deformation and damage by wetting and disintegration [1,2]. The disintegration mechanisms of soils are commonly associated with erosion and wetting disintegration. After water immersion, soil disintegration occurs as a water-soil interaction behavior. This property is called disintegration [3] and the wetting of soils in the geotechnical test procedure [4]. The study of the disintegration properties of soils has positive engineering significance and can be used to evaluate the aggression of soils. [PERSON] provided a reference for developing anti-erosion measures by studying the soil disintegration characteristics of collapsed walls in South China [5]. Also, soil slope stability relates to soil disintegration characteristics [1,6]. The degree of drying of the soil masses dramatically influences the degree of disintegration [7]. Many scholars have previously discussed the relationship between the initial water content state of the soil and the disintegration characteristics. The view is that the degree of soil disintegration intensity is inversely proportional to the water content. [PERSON] [8] analyzed the disintegration of residual granite soils in the collapse erosion zone in South China and investigated the effects of dry density, initial water content, and temperature on the disintegration of residual granite soils. [PERSON] [9] found that the water content of residual granite soil was only related to its initial disintegration rate. [PERSON] [10] found that when the water content increases, the disintegration rate decreases. Moreover, the disintegration phenomenon disappears when the water content increases to a particular value. [PERSON] [11] found that granite residual soil disintegration is more intense at low saturation. Conventional indoor tests are often used to study the disintegration mechanisms of soils [12]. The whole process of soil disintegration is visualized by immersing a specific size of in-situ soil block or remodeled soil block into water and recording the change in the applied tensile force (buoyancy force applied) to the soil block. In situ experiments have also been carried out [12]. In soil disintegration tests, four common indicators are used to evaluate the degree of disintegration: disintegration volume [5,6], disintegration modulus [10], disintegration rate [9,13], and disintegration morphology [14].