Master of Science in Civil Engineering (MSCE)


Civil and Environmental Engineering

Document Type



In the last decade, several fatal truck related crashes occurred on the elevated freeway over the Atchafalaya Basin. In an attempt to reduce the crash rates, the Louisiana Department of Transportation and Development implemented two policies to regulate the truck traffic on this rural divided freeway that has two lanes in each direction of flow. These policies restricted truck traffic to the right lane and reduced the maximum truck speed limit to 55-mph. On the other hand, maximum car speed limit was kept at 60-mph. The changes took place in 2003. While the policies were in effect, crash and traffic data were collected over the freeway. This study investigated the relationship between crash rates and traffic characteristics such as lane distribution of truck traffic, truck and car percentages exceeding the speed limits, difference between truck and car speeds, speed variance, truck volume, and lane occupancy. Multiple linear regression of total and truck-involved crash rates on the traffic characteristics showed that violation of the lane restriction and truck speed limit, truck speed variance, difference between car and truck hourly mean speeds, and lane occupancy were positively correlated with the crash rates.



Document Availability at the Time of Submission

Release the entire work immediately for access worldwide.

Committee Chair

Sherif Ishak