Evaluating the crash risk of powered two-wheelers in urban mixed traffic environments: a conflict threshold perspective.

The study investigates the crash risk of powered two-wheelers (PTWs) involved in multiple conflict types, with different vehicle classes constituting a mixed traffic stream. This study uses the extreme value theory to estimate the crash risk after establishing the conflict thresholds for potential rear-end and side-swipe conflicts by accounting for interacting vehicle types. The study considers four vehicle pairs involving PTWs: PTW-PTW, PTW-MThW (motorized three-wheeler), PTW-Car, and PTW-Bus.

Crash risk estimation of Heavy Commercial vehicles on horizontal curves in mountainous terrain using proactive safety method.

Heavy commercial vehicles (HCVs) face elevated crash risks in mountainous terrains due to the challenging topography and intricate geometry, posing a significant challenge for transportation agencies in mitigating these risks. While safety studies in such terrains traditionally rely on historical crash data, the inherent issues associated with crash data have led to a shift towards proactive safety studies using surrogate safety measures (SSM) in recent years. However, the scarcity of accurate microscopic data related to HCV drivers has limited the application of proactive safety studies in mountainous terrains.

Exploratory analysis of evasion actions of powered two-wheeler conflicts at unsignalized intersection.

The study investigates the braking and steering evasions of powered two-wheelers (PTWs) during severe conflicts observed at an unsignalized intersection. Traffic conflicts were detected using a surrogate safety indicator called anticipated collision time (ACT). Then the peak-over-threshold approach was used to identify the severe conflicts and the evasive actions.

Determinants of speed variability on the horizontal curves of two-lane undivided rural highways passing through mountainous terrain.

Drivers traversing the horizontal curves are expected to complete the deceleration manoeuvre on the tangent and transition curve and maintain a constant speed upon reaching the curve. However, this may not be true for the horizontal curves constituting a two-lane undivided rural highway passing through mountainous terrain. The objective of this study is to investigate the speed variability on a two-lane rural highway passing through mountainous terrain and to identify its determinants.

Assessing the crash risk of mixed traffic on multilane rural highways using a proactive safety approach.

The crash risk assessment of mixed traffic has been understudied due to a lack of pertinent data. In recent years, proactive methods have gained significant attention in transportation safety analysis because of their numerous advantages. In this study, we model and evaluate the effect of speed difference on the sideswipe crash risk of mixed traffic using a novel proactive safety indicator called Anticipated Collision Time (ACT).

Non-stationary crash risk modelling of powered two-wheelers using extreme value analysis of surrogate crash events.

Evaluating the impact of evasive actions such as braking and steering on the crash risk assessment of vehicles is a scarce endeavor due to the lack of relevant data. This study uses Extreme Value Theory to investigate and model the effect of evasive actions on the sideswipe crash risk of powered two-wheelers (PTWs) moving on multilane rural highways. The crash risk was projected from the observed sideswipe conflicts that were quantified using a surrogate safety indicator called anticipated collision time (ACT).

Speed-profile-based road segmentation for accident occurrence modelling for hilly terrains.

Modelling the accident occurrences per unit length of the road requires segmentation of road stretch. In the case of hilly terrains, homogeneity-based approach results in extremely small sections thus creating a biased accident data. This result is due to the high variations in geometry along the length of the road stretch.