Study On Comprehensive Evaluation Of Highway Alignment Quality In Mountain Area

Freeway alignment is the framework of expressway. The quality of linear design notonly controls the investment scale of roads, but also influences safety, comfort and economyof driving vehicles. As the topography, landscape and geomorphology conditions ofexpressway in mountain area are very complex, so the technical indicators of expresswayalignment are toughly limited which is hard to meet adequate standards for safe driving. Thereare security risks even on the roads consisting with technical specification. Many serious andmajor traffic accidents happen frequently, which poses a serious danger to the life andproperty of the people. Therefore, it has great significance to carry out the research onhighway alignment in mountain area.In view of quality problems brought by the existing road alignment design parametersselected, this article considers it is necessary to evaluate the linear quality of completedexpressway in mountain area to know the status quo of the linear in order to take effectivemeans and measures to ensure safety, comfort and economy of the mountain highway.Current studies on relevant evaluations of the quality of freeway alignment confined tosome aspect, which cannot reflect the linear quality unavoidably. What’s more, compared tothe plain area or the city zone, the environment of expressway in mountain area is morecomplex and has more influencing factors of alignment. In order to understand and master thecondition of the linear quality of expressway in mountain area, it is necessary to evaluate thelinear quality compositely, thus the paper puts forward the research on comprehensiveevaluation of expressway alignment in mountain area.The paper is from the needs of road users, combined with the mountainous highwaycharacteristics and requirements of the times to determine the content of the comprehensiveevaluation of the linear quality, that is, safety, comfort, economy and coordination with theenvironment of highway alignment in mountain area. Based on this, according to theevaluation principles, the paper uses characteristic analysis and quantitative methods to selecteleven indexes and establishes comprehensive evaluation system of highway alignment inmountain area.Through analyzing the advantages and disadvantages of existed evaluation methods, thepaper proposes the comprehensive evaluation method of highway alignment in mountain area,that is, synthetically index method. First, the paper quantitatively classifies the results ofcomprehensive evaluation of highway alignment in mountain area, evaluating thecomprehensive evaluation index of highway alignment. Secondly, the paper establishes layer structural model of comprehensive evaluation system of highway alignment in mountain areaand assures the proportion of every index by AHP. Finally, the paper analyzes and calculatesall indexes of different units, gains the comprehensive evaluation index and draws aconclusion of comprehensive evaluation of highway alignment in mountain area.Finally, the paper evaluates the instance of the Beijing-Zhuhai highway sections byidentifying the comprehensive evaluation index of highway alignment, and takes the result ofevaluation into verify.