Research On Comprehensive Application Of Highway Safety Evaluation Method In Mountain Area

Mountain highway takes great share in total mileage of highways in China. But for landform, climate condition and other environmental factors as well as highway design, Driving condition of mountain highway is so bad that the drivers happen to major traffic accidents on mountain highway. Thus, safety study on mountain highway is of significant meaning.Various aspects influence safety on mountain highway. Human factor is the major factor resulting in traffic accidents on mountain highways and the one hard to change. Meanwhile, this paper studied carefully the reason for the above phenomenon and found out problems at highway factors.Highway factors include geometry linear factors and non-linear factors like traffic facilities, highway structures and roadside environment. It is found in study only geometry linear factors meeting the requirements cannot ensure safety on mountain highway. Therefore, while evaluating safety on mountain highway, we shall take non-linear factors into consideration besides evaluation on linear factors.This paper firstly analyzed main factors influencing transport safety on mountain highway in terms of characteristics of mountain highway, and then sorted out and classified all these main factors into two types, namely linear factors and non-linear factors. According to the characteristics that linear factors can be quantified while non-linear factors are hard to be quantified, this paper adopted fuzzy comprehensive evaluation and related indexes of driving speed to evaluate the two types of factors.As to linear factors, this paper predicted driving speed at each highway section based on driving speed model provided in Highway Safety Evaluation Guideline, and made decision standard combining characteristics of mountain road as well as related indexes of driving speed for evaluation of overall safety of linear highway factors.As to non-linear factors, this paper collected and tidied experts rating with used Delphi method, then established index system and obtained the weight of related indexes, after which, made the experts rate safety of all indexes on the basis of in-site data and index parameters calculated from driving speed so as to evaluate safety of non-linear highway factors with fuzzy evaluation. Final conclusion that is subjective and real can be obtained through comprehensive analysis for conclusion of combination of the two evaluation methods.Lastly this paper analyzed the above study results and obtained evaluation conclusion consistent with the reality based on related data at the section where accidents frequently happen. The section is of good linear condition but sill occurs accidents frequently. The case proofed the idea that safety evaluation on mountain highway shall consider various factors and apply several methods for comprehensive evaluation.