Abstract:Soil shrinkage curves of different depths in slope disintegration profiles were measured using soil shrinkage tester (SS—1 type) to investigate the spatial variability of soil shrinkage characteristics. Results showed that in the process of dehydration, soil linear shrinkage ratio displayed increase firstly and then attained to steady level. The relationship between linear shrinkage ratio and water content can be fitted well by the Logistic model. Soil shrinkage curves of red soil layer and speckle soil layer could be apparently divided into three stages. The variation rate in soil linear shrinkage ratio showed an unimodal trend with the decreasing of soil water content, which was not suited to that of sandy soil layer. Linear shrinkage ratio increased when soil texture changed to heavy. Significant difference was found in shrinkage characteristic between different layers of slope disintegration body. Radial shrinkage strain was larger than axial shrinkage strain for red soil layer and speckle soil layer but it was opposite for sandy soil layer, which indicated that horizontal cracks mainly occurred in surface layer during the soil dryness dynamic process. Correlation analysis showed that radial shrinkage strain was positively correlated with sand content (r=-0.933); volume shrinkage strain and shrinkage limit were significantly correlated with clay content positively (r=0.891) and sand content negatively (r=-0.838), which indicated that soil shrinkage process was influenced by both soil texture and soil water state. Measures could be taken to reduce drastic variation of soil water content to prevent damage from shrinkage behavior in slope stability.