Characterization of artificially reconstructed clayey soil treated by polyol prepolymer for rock-slope topsoil erosion control

Steep gradient, bad natural ecological conditions, and lack of nutrient conditions necessary for vegetation growth led a large number of rock-slopes exposed and serious consequences felt with respect to ecological environment. The chemical material was used to improve the mechanical properties, erosion resistance and integrity of clayey soil, which could be the main materials in the artificial reconstruction of rock-slope topsoil. In the present study, polyol prepolymer is used as a chemical material added to clayey soil to achieve rock-slope topsoil erosion control. A series of laboratory tests were performed on clayey soil with different polyol prepolymer contents and also compared to a fallow one by which the effect on mechanical properties, anti-freeze-thaw behavior, evaporation, erosion resistance and vegetation growth were investigated. The results indicated that polyol prepolymer could increase the mechanical properties, which could be subdivided into improvements in cohesion and slight changes in internal friction angle. Meanwhile, the anti-freeze-thaw behavior, evaporation and erosion resistance of clayey soil also increased by the presence of polyol prepolymer. Low content of polyol prepolymer could promote the germination and growth of vegetation. The effectiveness of the clayey soil treated by polyol prepolymer in the restoration of rock-slope was verified in the field test.