Surrogate Safety Assessment of Unsignalized Intersections Under Heterogeneous Traffic Conditions in India: A Review of Pet, Speed-based Criticality and Vehicle-class Effects

Abstract

The reviewed studies show a progression from microsimulation and conventional PET analysis toward speed-enhanced criticality, vehicle-class analysis, trajectory-based interaction analysis, forceful-gap behaviour, conflict-severity indices, extreme-value modelling and systematic synthesis. Across the studies, motorized two-wheelers (M2W/MTW), autorickshaws (M3W), cars and light vehicles repeatedly emerge as important contributors to critical interactions, while pedestrian movements and forced gap creation introduce additional sources of conflict. Intersection geometry, traffic volume, traffic composition, speed, gap acceptance and time of day influence conflict occurrence and severity.