Investigating the Impact of Work Zones on Crash Severity by Comparative Analysis

Work zone safety has received much attention in recent years due to numerous highway construction projects that have resulted in many work zone crashes. To minimize the impact of work zones on roadway safety, the contributing potential factors that influence these risks need to be investigated. This can be done by identifying the possible causal factors in terms of crash severity and implementing countermeasures to ensure the motorist’s safety. In this paper, the impacts of the work zone presence on crash severity were identified by using descriptive analysis and then statistical modeling methods. Statistically robust models were developed by incorporating enhanced datasets that could be used to identify significant factors affecting crash severity. A major contribution of this study is that severity modeling parameters for work zone crashes were compared to non-work zone crash severity parameters to better distinguish work zone specific parameters. Logistic regression technique was applied to examine the best model or set of variables to correlate crash severity and possible causative factors for binary level outcomes. Modeling results were interpreted for both work zone and non-work zone conditions individually based on odds-ratio values. Comparison of the significant factors for work zone and non-work zone crash severity models, key findings and recommendation were also provided. Agencies can use these models and recommendations to improve safety at work zone locations by developing relevant countermeasures.