Raised Crosswalks on Entrance to the Roundabout - A Case Study on Effectiveness of Treatment on Pedestrian Safety and Convenience

摘要

Objective: A common concern in the use of a roundabout is providing adequately for the pedestrian. This unique roundabout layout, which introduces raised crosswalks directly at the roundabout entrance, as opposed to at a car length back, aims at improving safety and convenience for pedestrians at roundabouts. Methods: A preliminary evaluation of the layout was undertaken to establish its effectiveness in meeting study objectives. A quasi-experimental before-and-after study design was used to compare speeds on approach and immediately prior to the crossing to ascertain potential impact speed and implications for pedestrian safety. Compliance to crossing and crossing time were also compared in relation to safety and convenience outcomes. A questionnaire assessed pedestrian perception of the safety and convenience at the roundabout before and after treatment. Results: Results from this case study indicate that mean approach speeds (free speeds 30 m from crossing) reduced from 32.7 to 30.7 km/h and immediately prior to crossing, mean speeds reduced from 19.1 to 16.3 km/h. There was also a marked reduction in proportions of vehicles traveling at speeds that could elevate risk to pedestrians. Total crossing time after treatment reduced by around 4 s, and crossing compliance increased from approximately half to approximately 90 percent. Survey of pedestrians indicated positive response to the perceived safety and convenience post treatment. Conclusions: Preliminary results of the case study suggest positive safety and convenience outcomes. Implications for pedestrian safety include less exposure to traffic and lower risk of serious injury, particularly for elderly pedestrians; convenience outcomes include shorter waiting times to cross and greater compliance to the crossing. A larger study is required to substantiate the findings.