Evaluation of the Traffic Safety Benefits of a Lower Speed Limit and Restiction of Trucks to Use of Right Lane Only on I-10 Over the Atchafalaya Basin.

摘要

To improve traffic operation and safety, several states have implemented truck lane restriction and differential speed limit policies on freeways. In response to an 11-vehicle crash in September 2003, the Louisiana State Department of Transportation and Development (LADOTD) introduced such operational policies on the 18-mile elevated section of Interstate 10 over the Atchafalaya Basin, where trucks were restricted to the right lane and their speed limit was reduced to 55 mph. The speed limit for all other types of vehicles was also reduced to 60 mph. The primary objectives of this research study were to examine the traffic characteristics and truck compliance behavior to the newly implemented policies as well as evaluate the overall safety impact of such policies. Additionally, two opinion surveys were conducted to determine the truck drivers perception and opinions with respect to these policies. Traffic data were collected and analyzed for four different sites along the freeway corridor using multiple linear regression, pairwise comparison, and statistical two-sample T-tests.