Rusli Rusdi, Haque Md Mazharul, King Mark, Voon Wong Shaw
Queensland University of Technology (QUT), Centre for Accident Research and Road Safety-Queensland (CARRS-Q), 130 Victoria Park Road, Kelvin Grove, QLD 4059, Australia; Politeknik Sultan Mizan Zainal Abidin, Jalan Paka, 23000 Dungun, Terengganu, Malaysia.
Queensland University of Technology (QUT), Centre for Accident Research and Road Safety-Queensland (CARRS-Q), 130 Victoria Park Road, Kelvin Grove, QLD 4059, Australia; Queensland University of Technology (QUT), Civil Engineering and Built Environment, Science and Engineering Faculty, 2 George St., S Block, Room 701, Brisbane, QLD 4000, Australia.
Accid Anal Prev. 2017 May;102:153-164. doi: 10.1016/j.aap.2017.03.002. Epub 2017 Mar 15.
Mountainous highways generally associate with complex driving environment because of constrained road geometries, limited cross-section elements, inappropriate roadside features, and adverse weather conditions. As a result, single-vehicle (SV) crashes are overrepresented along mountainous roads, particularly in developing countries, but little attention is known about the roadway geometric, traffic and weather factors contributing to these SV crashes. As such, the main objective of the present study is to investigate SV crashes using detailed data obtained from a rigorous site survey and existing databases. The final dataset included a total of 56 variables representing road geometries including horizontal and vertical alignment, traffic characteristics, real-time weather condition, cross-sectional elements, roadside features, and spatial characteristics. To account for structured heterogeneities resulting from multiple observations within a site and other unobserved heterogeneities, the study applied a random parameters negative binomial model. Results suggest that rainfall during the crash is positively associated with SV crashes, but real-time visibility is negatively associated. The presence of a road shoulder, particularly a bitumen shoulder or wider shoulders, along mountainous highways is associated with less SV crashes. While speeding along downgrade slopes increases the likelihood of SV crashes, proper delineation decreases the likelihood. Findings of this study have significant implications for designing safer highways in mountainous areas, particularly in the context of a developing country.
山区公路通常与复杂的驾驶环境相关联，这是由于道路几何形状受限、横断面要素有限、路边特征不当以及恶劣天气条件所致。因此，单车（SV）碰撞事故在山区道路上的占比过高，尤其是在发展中国家，但对于导致这些单车碰撞事故的道路几何、交通和天气因素却鲜有关注。因此，本研究的主要目的是利用从严格的现场调查和现有数据库中获得的详细数据来调查单车碰撞事故。最终数据集总共包含56个变量，代表道路几何形状，包括水平和垂直线形、交通特征、实时天气状况、横断面要素、路边特征以及空间特征。为了考虑现场内多次观测产生的结构化异质性以及其他未观测到的异质性，该研究应用了随机参数负二项式模型。结果表明，碰撞发生时的降雨与单车碰撞事故呈正相关，但实时能见度与之呈负相关。山区公路沿线有路肩，特别是沥青路肩或更宽的路肩，与较少的单车碰撞事故相关。虽然在下坡路段超速会增加单车碰撞事故的可能性，但适当的标线会降低这种可能性。本研究的结果对于在山区，特别是在发展中国家的背景下设计更安全的公路具有重要意义。
