Analysis on Vegetation Effect of Ecological Bank Slope Protection Structure in Expansive Soil Matrix Environment

Existing researches on the protection of expansive soil bank slopes focus on soil properties and slope stabilization measures, and there are few studies on the ecological restoration of artificial wound surfaces in expansive soil areas due to engineering construction.In this paper, the bank slope protection methods for the watershed section of the expansive soil concentration area have been summarized through data combing based on the national major water transfer project "Yangtze River-to-Huaihe River Water Transfer Project".Moreover, based on the field effect analysis of the test section, the vegetation growth effect of the typical ecological bank slope protection section in the expansive soil area has been studied.The research results show that the survival rate of sprayed bermudagrass in the test section is extremely low.The fundamental reason is that the replacement of cement modified soil isolates the connection between the upper and lower water; the survival rate of bermudagrass planted by stem in the test section is high with quick forming turf speed, indicating that the planting method of vegetation has a greater impact on its survival rate; the local native wild plants grow vigorously, with legumes and compositae as the dominant species, which can be used as early soil-fixing pioneer vegetation; the test section adopted two types of ecological bank slope protection structures:a large sash structure and a water-soil conservation blanket, and there were serious soil erosion and poor water retention problems, and targeted structural optimization measures were proposed.The research results have reference value for the construction of Yangtze River-to-Huaihe River Water Transfer Project and the bank slope protection projects in other expansive soil areas.