Research In Envrionmental Route Selection Pattern Of Highway In Mountain Areas Based On Project Of North Segment Of Xipan Narrow Mountain Pass

Highway construction is one of the most influential human activities to social economy and oecological environment. In recent years, highway construction with much investment, large scale, high speed and long mileage bring about increasingly environmental pollution to mountain areas. As route selection is important to keep the compatibility between highway construction and environmental protection, it's urgent to discover a way or policy which not only has research value in theroy but also has profound significance in reality.This paper takes the route design of north segment of mountain pass on Xipan express highway as the background and by use of analytical method of structrual model it determines a design pattern for general route selection of highway along rivers in mountain areas under which special route desgin work between Puba and Miyi is finished. Firstly, according to the design conception that hingway construction and environmental protection is equally important and highway should be constructed to be more safe, more economic and more envornmental protection and through analyzing, researching and combined new controled factors in many express highway route design, this paper presents the main facors and relationship which influnce environmental route selection of highway along rivers in comlicated mountain area and a general structral figure of main factors that influnce route selection of highway along rivers in mountain area is achieved. And then the compatible problem between highway engineering and environment is researched, the limitation of environmenat along rivers to route selection and the corresponding engineering measures of avoidance, prevention and cure is introduced and how the route selection is compatible with existing railways under the condition of good route position of Chengkun railway and the effects of highway construction on the reservation of water and soil are discussed, thereby adjusted design working process of route selection based on compatibility between north segment of narrow mountain pass along Xipan road along rivers and environment ispresented. And then this paper introduces the achievements in working-drawings phase and route design. At last, it draws conclusions about the applicability and shortage of the scheme that analytical method of structrual model is applied to decide the main factors and decision-making logic layer in route selection and prospect the development tendancy of route selection. Hence, this paper has some reference value to route selection of highway along rivers in complicated mountain areas.