Unevenness of intersection pavement and bicycle safety

Bicycles are environmentally friendly and easy to operate. However, the bicycling environment in Japan is inadequate compared with many developed countries. Bicycle accidents have been increasing in recent years, and safety measures are needed to improve the bicycling environment. Although road surface conditions have improved, as reflected in the recent barrier-free policy for elderly and disabled pedestrians, an uneven surface between the road and the crosswalk can help to reduce accidents by reducing running speed. Because the most frequent type of bicycle accident is a collision with a car at an intersection, the accident-prevention potential of an uneven surface at an intersection crosswalk was examined. Students were asked to run along specific routes, and speed and vibration changes when they passed through intersections were measured. On the basis of the results, an analysis was made of what road environments would benefit from an uneven crossing surface. An uneven surface was found to reduce speeds at intersections with limited sight distance. However, other appropriate safety measures must be applied to reduce bicycle speed when an uneven crossing surface cannot be used because of the barrier-free policy.