Analysis of Accident Characteristics and Causes for Bridge-Tunnel Group Section of Mountainous Expressway

Abstract

Bridge and tunnel grouping has become a typical characteristic of mountainous expressway especially in west area of China. This paper analyzes and performs a great deal of investigations in order to study and control the accidents of bridge-tunnel group sections. Firstly, the statistical distribution of accidents according to time, climate, and accident pattern and vehicle type in bridge-tunnel group section were analyzed. From aspects of human factor, road alignment, safety facilities, pavement states, traffic conditions and nature conditions, accident influence factors for bridge-tunnel group were studied comprehensively. Finally, the result of the research can help to avoid design defects and support maintaining, traffic management and accident control of mountainous expressway. In recent years, the main investment of highway construction in China is shifting from plain to mountainous areas, which helps improve the economy of related area. Expressways require better alignment elements than ordinary roads. So, high embankments or deep through cuts are in common uses. But sometimes, embankments or through cuts were so high or deep that they were infeasible in economy or technology. So, bridges and tunnels substitute for them and bridge-tunnel group appearances (Liu 2009) which is obviously different from general sections. The driving environment of bridge-tunnel section varies frequently along the road, which leads to poor safety performance. So, it is very important to study the safety problems at bridge tunnel junction and bridge-tunnel group sections. In this paper, bridge-tunnel group of typical mountainous expressways were investigated and the characteristics for traffic accident were analyzed. Finally, the conclusions were proposed for improvement of bridge-tunnel group section.