Are signalized intersections with cycle tracks safer? A case-control study based on automated surrogate safety...

Area of Science:

• Urban planning
• Transportation engineering
• Traffic safety

Background:

• North American cities are increasingly implementing cycle tracks to enhance urban cycling and safety.
• Limited research exists on the specific safety impacts of cycle tracks at intersections, particularly concerning interactions with turning vehicles.

Purpose of the Study:

• To investigate the safety effects of cycle tracks at signalized intersections.
• To analyze cyclist-vehicle interactions using post-encroachment time as a surrogate safety measure.

Main Methods:

• A case-control study design was employed in Montreal, comparing intersections with and without cycle tracks.
• Video data from 23 intersections (over 90 hours) was analyzed to extract cyclist and vehicle trajectories.
• Ordered logit models with random effects were used to assess safety impacts.

Main Results:

• Intersection approaches with right-side cycle tracks showed improved safety compared to those without.
• Left-side cycle tracks demonstrated significantly greater safety benefits than intersections lacking them.
• Higher turning vehicle flow increased the risk of dangerous cyclist-vehicle interactions, while larger cyclist group sizes reduced this risk.

Conclusions:

• Cycle tracks play a crucial role in enhancing cyclist safety at signalized intersections.
• The placement of cycle tracks (left vs. right) significantly influences their safety effectiveness.
• Future research should validate these findings with extended video data collection periods.