Analysis of Accidents at Long-Term Construction Projects in Texas

The report presents an analysis of accidents at five long-term freeway construction projects in Texas during 1984 – 1988. Total accidents on the mainlanes increased an average of 28.7 percent during construction. Severe accidents on the mainlanes increased by a greater percentage, on the average, than did PDO accidents (38.8 percent versus 24.9 percent). Nighttime accidents on the mainlanes increased by a greater proportion than did daytime accidents (37.4 percent versus 24.4). Frontage road accidents at the five projects increased by an average of only 2.4 percent during construction. The average changes in PDO and severe accidents, daytime and nighttime accidents, and in the various accident type categories on the frontage road were also found to be negligible. A statistical test of homogeneity of the changes in accidents from project to project indicated that the average changes in total mainlane accidents, severe accidents, single vehicle, and multi-vehicle (excluding rear-end) accidents were consistent from project to project, and could be used as reasonable estimates of the expected impacts for future projects.