| Summary: | 碩士 === 國立交通大學 === 交通運輸研究所 === 98 === The accidents could be sorted to section and intersection by locations, and the intersections could be classified into signalized and unsignalized intersections. Intersections with high volume of traffic usually use traffic singals to separate the vehicles from different direction. But the volume of traffic in intersection without exceeding the criteria usually only install warning or prohibition sign (or marking) to promote visibility of intersection and confirm the right of way. In consideration of the accidents in signalized or unsignalized are different, this study focuses on the accidents of unsignalized intersections to find the influential factors of accident severity, and to propose the safety improvement measures.
This study is based the accident data of unsignalized intersection in 2008 in Taipei City. The severity is classified into three categories: “property damage only”, “injury” and “incapacitating and fatal injury". Depending on literature review and practical experience, there are 19 possible influential factors including “driver”, “vehicle”, “road”, “environment” and “traffic control”. Through the development of a most suitable logit model with maximum number of factors, we then explore the similarity of the classification of severity by nest logit model, and to investigate the difference of parameters by mixed logit model.
The results show that mixed logit model can well describe the accident severity for unsignalized intersections. For incapacitating and fatal injury, there are six positive variables (ex. cross between the same traffic flow etc.) and five negative variables (ex. net marking etc.). For injury, there are nine positive variables (ex. cross between the differ traffic flow etc.) and five negative variables (ex. male etc.).In this study, the proposed safety improvement measures in traffic engineering are to promote visibility of intersection, change the marking for parking near the intersection and integrate ITS with traffic sign. In enforcement, the measures are to intensify the effectiveness for flashing light and stop or yield sign (marking), ban parking near the intersection. Meanwhile, the measures in education are to promote the habit of drivers to use the reflectors and look out the rear vehicles before turning etc.
|
|---|
