The Research Of Safety Evaluation Method Based Operating Speeds On Montanic Highway

Road traffic is a complex large-scale system, in which the various elements of the people, vehicles, road and the environment are mutual influence. The safety of vehicles is actually the result of the coordination of the various elements. Terrible road conditions cause traffic accidents most directly, in the condition of low-grade highways in the mountain area.The road safety audit takes the road user's safety as the center, from preventing traffic accident and reducing the possibility of the accident. The road safety audit examines the whole process of the road construction, including the plan, the design, the construction and the period of service. The road safety audit can exposit the accident potential hazard factor and the security performance.This paper researches the safety evaluation method for mountain area, which relies on the road safety audit project of Haizi Mountain to Zhubalong of national road 318; References the safety evaluation methods in < Highway Project Safety Evaluation Guide> and "DuWen Highway Safety Evaluation", and considers the characteristics of low-grade highways in mountain area, the potential safety problems are investigated and classificated by speed evaluation method.Firstly, the paper analyzes the necessity of the highway safety evaluation and domestic and international current research situation based on analysis of the situation of highway traffic safety. The research content and approach are established to give this thesis a good localization through analyzing and researching the current situation.Secondly, the paper explains the concept of operating speed, then discusses the application of the speed in road projects, thereby operates the rationality of evaluating highway safety based on the speed, provides a theoretical basis for the paper.Thirdly, the operating speed forecast. At the foundation of sufficient research on the achievement of the domestic and external, the running speeds forecast models are constructed in 5 different kinds of highway sections (straight line section, slope section, curve sections, curve and slope section, bridge and tunnel section).It is the focus of this paper, which is also the foundation of the follow-up to identify potential safety problems.Moreover, operating speed evaluation indexes are selected based on operating speed forecast. The indexes include continuity, speed difference, deceleration, horizontal curve radius, minimum line length, super elevations and so on. Which are important to prevent the potential safety problems, find out the inconsistency of the whole highway, and determine the security classification levels of the mountain road.Finally, an instance analysis adopted the running speed safety audit method of this text is carried on in a section of Haizi Mountain to Zhubalong of national road 318. Including the highway section division, running speed calculation, running speed harmony analysis, running speed with design speed harmony analysis, the potential accident audit, the safety grade division, etc. The running speed safety audit method can be understood and the defect can be found thoroughly through the instance analysis. In a word, security appraisal is a technology of controlling the system loss, the process of appraising raises the safety management level, it is a safety management method which reflects from passive to active, from treatment after the accident to defending before the accident , from experience to scientific security office procedure.