Evaluation of Intersection Countermeasures on High-Speed Rural Multi-Lane Facilities.

摘要

The primary objective of this study is the evaluation of the effectiveness of several proposed safety treatments at two intersections in Habersham County, Georgia. The intersections selected for this study had high crash rates leading to a Georgia Department of Transportation proposal for various safety improvements. To evaluate the impact of the safety treatments, this study focused on an evaluation of various surrogate measures of safety: speed, acceleration/deceleration rate, and Post Encroachment Time (PET). The study used video recording as the primary data collection methodology and used custom software, developed as a part of the project, for data reduction of the resulting videos. GPS probe vehicles were used to provide a ground truth reference. Data collected showed that the treatment had negligible impact on the behavior of the vehicles studied regarding the surrogate measures considered. As a follow up study, the use of PET data as a surrogate measure was further explored. The objective of this investigation was to determine the utility of using PET to rapidly determine the potential safety impact of a treatment. For this investigation data were collected at two pairs of intersections. Each pair was selected to be of similar geometry and volumes but of different crash rates. For the given intersections PET demonstrated the potential to distinguish between highly significant safety differences although it remains uncertain what magnitude of safety difference may be identified.