Freeway single and multi-vehicle crash safety analysis: Influencing factors and hotspots

Publication date: November 2019Source: Accident Analysis & Prevention, Volume 132Author(s): Xuesong Wang, Mingjie FengAbstractSingle-vehicle (SV) and multi-vehicle (MV) crashes have been recognized as differing in spatial distribution and influencing factors, but little consideration has been given to these differences as related to hotspot identification. For the purpose of better hotspot identification, this study aims to analyze influencing factors of SV and MV crashes and to explore the consistency between SV and MV hotspots. Crash data, roadway geometric design features, and traffic characteristics were collected along the two directions of a 45-km freeway section in Shanghai, China. Univariate negative binomial conditional autoregressive (NB-CAR) and bivariate negative binomial spatial conditional autoregressive (BNB-CAR) models were developed to analyze the influencing factors and specifically address (1) site correlation between SV and MV crashes within the same freeway segment, and (2) spatial correlation among different freeway segments within the same direction. The modeling results showed substantial differences in the significant factors that influence SV and MV crashes, including both roadway geometric features and traffic operational factors. A non-negligible site correlation was found between SV and MV crashes. Taking into account the site correlation, the BNB-CAR model outperformed the NB-CAR model in terms of parameter estimation and model fitting. For hotsp...
Source: Accident Analysis and Prevention - Category: Accident Prevention Source Type: research