Study On The Site Selection Of Highway Exit

Reasonable site and type selection of highway exit can avoid the randomness, blindness and repetition of the decision and layout; it is one of the central prophase job during the prophase of highway construction. The rationality of the exit position influences the traffic capacity of expressway and regional economic impetus function.This paper uses the research technique that combine theoretical analysis and protocols, qualitative analysis and quantitative analysis, to analyze and study the substance systematically and thoroughly about site and type selection of highway exit and scheme evaluation etc, that is under the site selection of highway exit general theory.Based on the status of research works and existing problems, fundamental principle and influencing factor about site and type selection of highway exit are summarized, and highway exit is classified from the transportation angle.Combining the research about highway exit characteristic and regional economic influence, site selection, the steps for establishing the scheme and parameter design for type selection of highway exit are analyzed, exits in quantity and position in one area are determined; it clarifies the scheme can have different emphasis point to different exit, indicates the length of deceleration lane in current standard is shorter in some special situations.It studies the synthetically evaluation method, establishes the comprehensive evaluation system, sets up combined weight—grey correlation projection method, combines analytic hierarchy process (AHP) and the entropy weight method to determine the index weight, evaluates the scheme using grey correlation projection method. The evaluation model is verified through the actual project case, and indicates this method has better practicability.