Research Of Freeway Subgrade Drainage Technology In Mountain Areas

With the economic take-off, highway construction in our country has entered a rapid development period since the late eighties of last century, at the same time, the problem of damaged roads caused by water is incresingly serious, and it has seriously influenced the development of freeway. In order to improve freeway drainage design standards in mountain areas, give full play to the performance of drainage facilities, it is necessary to start Reseach of Freeway Subgrade Drainage Technology in Mountain Areas.Through surveyed and analyzed the environment of mountain areas in the south of ShanXi province, and the investigation of diseases of freeways drainage facilities in ShanXi province, we summed up the types of diseases of freeway drainage facilities in mountain areas, and analyzes the cause. Freeway drainage diseases in mountain areas are caused by a variety of factors, including design out of line with the theory, the lack of summarize and guide of the experiences of control destroyed, management ignored drainage and protection works, drainage systems incomplete and poor geological conditions and so on.Groundwater status of mountain freeway is very complex, the paper summarized scheme of how to layout underground drainage facilities in the different topographic and geologic conditions.Through the analysis of the applicability and discharge capacity of common ditches, we proposed the design steps of sewer filter layer, combined with freeway soil characteristics in mountain areas, we proposed the method to set freeway sewer filter layer in mountain areas.Based on the drainage capacity and stability of drainage facilities, the papper researched the reasonableness of the surface drainage facilities and underground drainage facilities, and we evaluated the reasonableness of typical surface drainage facilities and underground drainage facilities by fuzzy synthetically evaluation, the results prove the credibility and feasibility of the system.