Research On Relationship Between Driver's Visual Characteristics And Alignment Indicators Of Long And Steep Slope In Mountainous Area

Research on alignment indicators of long and steep slope in mountain area, is important for design of long and steep slope and improvement of traffic safety. In the past, researches usually used automobile dynamic puality as the standard on the research of the alignment indicators and lacked consideration of the human factor, particularly on the consideration of driver who has important significance in road safety. This paper, based on visual characteristics of the driver, pays attention to people-centered concept, select visual indicators, the use of advanced measuring technology and test equipment and engineering aspects of the mathematical theory, real vehicle testing, and experimental data qualitative and quantitative analysis.This thesis, based on the drivers'visual characteristic, emphasizing on the idea of people foremost, chooses visual indexes, and uses advanced measuring technique and machines and theory of engineering mathematics, by doing vehicle tests, qualitatively and quantitatively analyzes test datum, finally obtains evaluation method of highway alignment indicators. Firstly, based on visual characteristic theory, the index for evaluating alignment consistency of long and steep slope of freeway in mountain area is ascertained. In the thesis, three indexes are chosen, in which are visual orbit, variance ratio of pupil area, and ratio of blink number to fixation number. Secondly, the tests are designed according to research objective. In long and steep continuous slope section of freeway in mountain area, highway alignment exists as combination, so this thesis takes the common and representative steep slope and flat slope inserted into curves of different radius as test section, meanwhile samples datum of viewpoint movement orbit, eyes movement, speed and alignment indexes with car drives in long and steep continuous slope of freeway in mountain area. Finally, this part is the main part of the thesis, and each index is researched as a chapter, respectively and the relation analysis between visual index and highway alignment is studied in two aspects: one is the difference of drivers'visual characteristic influenced by different curve; the other one is visual characteristic analysis in steep and flat slope, which is about the influence of visual characteristic by steep and flat slope when driver is driving.The conclusions from the research show that: when car runs in long and steep continuous slope section, the highway alignment of frequency F(v) is 2.2 /one hundred meter; the thesis also analyzes the relation between pupil area variance ratio and highway alignment, and proposes the value 6.0 and 25.0 of pupil area variance ratio as the standard of judging highway alignment; the thesis researches the relation between blink number, fixation number and alignment, and chooses the threshold value 0.20 of the ratio of blink number to fixation number as the standard of judging highway alignment. Based on the above three indicators, thesis concludes that the level of the minimum radius of 460m.