ISM Model of Factors Influencing Traffic Safety at Expressway Work Zone

As a dangerous area of expressways, work zones are home to traffic congestion and various traffic incidents frequently occur due to the complicated traffic status. According to the vehicles' driving characteristics in expressway work zones and a literature review, 23 factors on expressway work zone safety are selected from the aspects of driver, vehicle, road and traffic environment. Based on finding out the direct and indirect relations among these factors, a multilevel step-up structural model on factors involved in the traffic safety of expressway work zones is developed using the interpretative structural modeling (ISM) method. In terms of the results of this hierarchical modeling, the key factors contributing to expressway work zone safety are presented and relevant suggestions are put forward to provide a scientific reference for construction organization, traffic control and environment improvement at expressway work zones.