Investigating the Impact of Surrounding Vehicles on Merging Location Choice in Work Zones

Taper areas, where most merging events take place in work zones, have the highest crash probability within a work zone. To understand the factors contributing to the choice of merging location in work zones, this study presents the results from an observational study of merging events in two work zones in New South Wales, Australia. A binary logit model was developed to model the merging location choice (within or outside the taper area) as a function of various explanatory variables, such as lane closure type, merging time, and the presence/absence and type of surrounding vehicles around a merging vehicle. The results showed that slow-lane closures are associated with increased merging probabilities in the tapered area, indicating that drivers tend to merge closer to perceived high-risk areas within work zones. The presence of light vehicles in the current lane-leading position significantly decreases merging probabilities in the taper, whereas the presence of vehicles in the target lane leading position increases the likelihood of merging within the taper. The presence of heavy vehicles in the target lane does not decrease merging probabilities within tapers,  challenging conventional assumptions regarding the roles of heavy vehicles in work zone safety risks. The findings of this study provide valuable insights into merging dynamics in work zones, emphasizing the need for tailored traffic management strategies to enhance the safety and efficiency of roadways. The findings contribute to ongoing discussions on work zone safety and offer evidence-based recommendations for transportation agencies to optimize traffic flow and mitigate risks within work zones.