Research On Evaluating Synthetic System Of Freeway Alignment Quality

Freeway alignment is the framework of highway. The quality of linear design not only control the investment scale of roads, and influence safety, comfort and economy. of driving vehicles. The assessment of linear quality is a large and complex system, which haves many factors and more aspects. Current studies on relevant evaluations of the quality of freeway alignment confined to some aspect , that cannot reflect the linear quality unavoidably. In order to understand and master the condition of the linear quality of existing roads, it is necessary to evaluate the linear quality compositely, thus it puts forward the research on synthetic evaluation system of the freeway alignment quality.This article selected representative synthetic evaluation index of the linear quality and constructed comprehensive evaluation-index system of freeway alignment quality through analysing the safety, comfort, economy and coordination with the environment of highway alignment, and combined with the specific characteristics of index, the method of index is studied in detail. It researched quantification and the dimensionless processing of different property index, and solved data problems of indicators qualitatively and the problem to compare index uniformly. It studied the method to determine the assessment index values, proposed the way to determine the weight based on AHP / entropy method. Using fuzzy recognition principle, according to line quality criteria for the classification level,it put forward evaluation model and method on synthetic quality of freeway alignment. The feasibility and reliability of the evaluation system and method is proved through evaluating alignment quality of loop expressway in Chongqing comprehensively. The problems and future direction of evaluation model and method according to the calculation procedure and evaluation conclusion. The value of the paper lies that making builder and managers of roads understanding the alignment quality comprehensively through comprehensive evaluation, and providing theory basis and the technical support to construct and manage freeways more targeted.