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Facilitating bicycle travel using innovative intersection pavement markings.
Peter B Ohlms1, Young-Jun Kweon1
1VDOT, Virginia Transportation Research Council, 530 Edgemont Road, Charlottesville, VA 22903, USA.
Journal of Safety Research
|December 17, 2018
Summary
New traffic control devices like bike boxes and turn boxes had mixed results in improving cyclist safety and compliance at intersections. Some infractions decreased, while others increased, with inconsistent proper usage by bicyclists.
Area of Science:
- Urban Planning and Transportation Engineering
- Traffic Safety Research
- Human Factors in Transportation
Background:
- Intersections pose safety challenges for cyclists.
- New traffic control devices, including bike boxes and two-stage turn queue boxes, have been implemented to improve bicycle travel.
- Understanding the real-world effectiveness of these interventions is crucial for urban mobility planning.
Purpose of the Study:
- To evaluate the impact of newly installed bike boxes and two-stage turn queue boxes on cyclist behavior and traffic safety.
- To assess changes in traffic infractions and conflict events following the implementation of these bicycle infrastructure elements.
Main Methods:
- Video data were collected for three days before and five days after the installation of bike boxes and turn boxes at a Charlottesville, Virginia intersection.
- Observed data included traffic volumes, infractions, and conflict events (near-misses).
- Statistical analysis used the Wilcoxon signed-rank test to compare pre- and post-intervention periods due to non-normal data distribution.
Main Results:
- The study yielded mixed results regarding traffic infractions; some decreased while others increased depending on the infraction type and intersection approach.
- Bicyclist usage of the new infrastructure was inconsistent, with some cyclists using the markings properly and others using them improperly or not at all.
- Observed conflict events and near-misses were tallied to assess safety impacts.
Conclusions:
- The effectiveness of bike boxes and two-stage turn queue boxes in improving cyclist safety and compliance at intersections is not definitively established by this study.
- Further research and potential design modifications may be needed to optimize the performance and user adoption of these traffic control devices.
- Mixed results highlight the complexity of integrating bicycle infrastructure into existing traffic systems.
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