Study On Comprehensive Evaluation Of Highway Alignment In Mountain Area

The highway in mountain area is completely closed, multi-lane, with central median, the entire interchange, centralized management, access control, multiple security services facilities complete high standards for road vehicles. A high-speed highway traffic, the characteristics of large capacity. However, all kinds of major accidents may happen frequently.As alignment is the major segment of highway,and be toughly limited by the terrain condition of mountain area, it has great significance to carry out the research on highway alignment in mountain area.The paper takes the require of highway alignment in mountain area into account as a comprehensive system, and highway alignment in mountain area should be met safety, comfortableness and consistency of the three at the same time, through characteristic analysis and quantitative methods are combined to select appropriate nine indexes including slope length under certain longitudina gradie for the comprehensive evaluation of highway alignment in mountain area. The paper analysises the correlation between comprehensive evaluation indexes and speed, compares the different roles between design speed and operating speed during the design of alignment, with operating speed as the basis of comprehensive evaluation index calculation, and identifies the operating speed calculation model.The paper establishes a comprehensive evaluation system of highway alignment in mountain area, including the comprehensive evaluation index collection of highway alignment in mountain area, the quantitative classification of the evaluation results and the method of comprehensive evaluation of highway alignment. The comprehensive evaluation index collection of highway alignment set by the three levels, including the target, rule, and index. The paper assures the proportion of every index by AHP. Quantitativly classifies the results of comprehensive evaluation of highway alignment in mountain area, evaluating the comprehensive evaluation index of highway alignment. Finally, the paper evaluate the instance of the Beijing-Zhuhai highway sections by identifying the comprehensive evaluation index of highway alignment, and takes the result of evaluation into verify.