Proactive Safety Assessment at Unsignalized T-Intersection Using Surrogate Safety Measures: A Case Study of Bhopal City

Every year, road accidents cost billions of dollars and damage millions of people around the world. Among all critical points, intersections pose special safety concerns because of the high probability of critical conflicts resulting from unsafe driver actions and maneuvers. As a result, assessing road safety, particularly at uncontrolled T-intersections in mixed traffic, becomes critical. Over the last few decades, Surrogate Safety Measures (SSM) have attracted a lot of study attention for analyzing road safety issues. These approaches are designed to be proactive, that do not rely on collisions, and require shorter observation time periods to create acceptable safety assessments. In this study, two uncontrolled intersections in Bhopal City were chosen as research areas for safety evaluation by adopting the Surrogate Safety Assessment approach. The study focused on crossing conflicts among right-turning vehicles and through traffic as they are considered severe among other conflicts. Post-Encroachment Time (PET) and conflicting vehicle speed of through traffic are used to determine critical conflicts. Further, Encroachment Time (ET) is taken as surrogate indicators to identify severity levels of right turning movements using the clustering technique.