An Exploratory Study of Speed Limit Compliance in Missouri Work Zones

This study evaluated the speed compliance with the posted speed limit both quantitatively and qualitatively using objective and subjective data analysis. Free flow speed data for three work zones on I-44 in Missouri were used for the objective evaluation. Speeds analyzed for cars and trucks were distributed normally. Construction activity had a significant effect in reducing the speed of vehicles. Results indicate that the speeds of vehicles were statistically higher than the speed limit regardless of the construction activity, when the lane width was not reduced. The subjective evaluation investigated the drivers' perception of driving through the work zone by using a survey questionnaire. About 40% of drivers indicated that the speed of other drivers were less than the speed limit which contradicted the results of the objective analysis. More than 70% of drivers experienced delay and more than 90% agreed that construction activity reduced their speed which was ascertained from the results of the objective analysis.