Vehicle Speeds Variance Analysis in a Freeway Work Zone Based on the K-S Test

To develop effective speed-limit strategies and improve driving safety for work zones, the variance analysis for vehicle speeds in work zones was explored. A method on variance analysis for vehicle speeds in work zones was proposed based on the K-S test and validated the method in carriageway lane closure work zones on a dual-way-four-lane freeway. The method of P-P probability plots was utilized to verify normal distribution for the speed samples of trucks and cars in different traffic control divisions of carriageway lane closure work zones and the method of two samples K-S test was adopted to verify the variance significance of vehicle speeds between test sections, respectively. The research results show that the speed samples of trucks and cars are normal distribution and there is significant variance in vehicle speeds in different traffic control divisions of carriageway lane closure work zones.