Applied Research On Soil And Water Loss Impact Index For Expressway Projects

Land occupation, vegetation destruction have serious influences on the environment in the process of expressway construction which result in soil and water loss. Hence, the study of Soil and Water Loss Impact Index(SWII) by means of evaluating the impact of soil and water loss after the construction, recognition of problem in time to instructdesign and construction has significant meaning to realize expressway construction in harmony with the development of society, economy and environment benefits.To evaluate quantitatively the soil and water loss impact expressway projects requires a large number of research on expressway projects. Analyze the regulation of soil and water loss by construction, according to SWII to compare expressway projects in different erosion areas in quantitationfrom the aspect of management.By the method of the Soil and Water Loss Impact Index(SWII), this paper undertakes the quantitative calculation and evaluation of the106Expressway Soil and Water Conservation Schemes, and analyzes the key factors of Soil and Water Loss in different Erosion Areas. According to the results of SWII, the Expressway Projects are divided into three types: high-influence projects with the value of SWII higher than0.387; medium-influence projects with the value of SWII between0.258to0.387; low-influence projects with the value of SWII lower than0.258.With the standard of SWII, approve the project with lower SWII value first, to those projects with higher SWIIvalue approve after the necessary modification. For all the expressway projects execute the same standard to evaluate in order to ensure the rationality of investigation and approval. In the end, this paper also puts forward different technical requirements for different type of Expressway Projects which are soil and water loss preventive criteria, soil and water conservation engineering grade, soil and water conservation measure configuration, request of construction craft.