Recommended CitationTarko, A. P., M. Islam, and J. E. Thomaz. Improving Safety in High-Speed Work Zones: A Super 70 Study. Publication FHWA/IN/JTRP-2011/09. Joint Transportation Research Program, Indiana Department of Transportation and Purdue University, West Lafayette, Indiana, 2011. doi: 10.5703/1288284314622.
Super 70 was an urban reconstruction project (March-November 2007) along I-70 in the central part of Indianapolis. INDOT applied in that project several innovative and traditional solutions. This study investigates the safety effect of the solutions. Advanced econometric models were applied to study both the spatial differences in the risk of crash on different roads inside and outside of the construction zone and short-term fluctuations in response to changes in traffic, weather, and traffic management. The single most successful management strategy was rerouting heavy vehicles (13+ tons) on alternative interstate routes. The second significant source of safety benefit was jointly generated by police enforcement, reduced speed, and other traffic management strategies. The safety benefit generated by the two sources was estimated to be 100 crashes saved inside the work zone during the nine months of the road construction. Widening shoulders was indicated as an additional means of improving work zone safety. The study could not confirm that the moveable barriers and consequently adjusting the number of traffic lanes to traffic volumes brought any direct safety benefits inside the work zone. The recommendations could be incorporated to the INDOT supporting materials for traffic management in high-speed urban work zones. The risk prediction equations can be applied to real-time detector data and weather information to to assess the risk and identify high-risk conditions. Adequate warning messages could be displayed via VMS placed in advance of work zones.
urban work zone, traffic safety, high-speed road, statistical analysis, logit model, disaggregate data analysis, SPR-3249
Joint Transportation Research Program
Indiana Department of Transportation
West Lafayette, Indiana
Date of this Version