Safe System Intersection Application for the Edmonton Capital Region- Pilot Project

摘要

The Capital Region Intersection Safety Partnership (CRISP) conducted a pilot project on engineering applications of the Safe System approach. CRISP retained the Monash University Accident Research Centre (MUARC) in Melbourne, Australia to lead the project and apply the Safe System road safety philosophy to selected 'poorly performing' intersections in the City of Edmonton, Strathcona County and City of St. Albert (CRISP partner jurisdictions). The intent was to highlight differences between a traditional road-safety approach and a Safe System approach which might inform policy development. Safe System is a road safety philosophy believing that an individual's safety is paramount to any other benefit which the transport network provides. Safe System does not tolerate serious injury and fatal collisions, regardless of the benefits that road users receive. This contrasts with current safety attitudes. For example in 2010 there were 2,227 fatalities and 11,226 serious injuries on Canadian roads that are accepted as a consequence of our transportation system. Despite this philosophical disparity there is evidence that attitudes are changing. MUARCS literature review found a growing world-wide willingness to consider intersection geometries that emphasise reduced speeds or improved impact angles. Roundabouts in particular are increasingly seen as a reasonable and safer alternative to traffic signals. For this project MUARC applied their Kinetic Energy Management Model (KEMM) to sixteen problematic intersections in the Capital Region. KEMM is a conceptual model for evaluating the transfer of kinetic energy exchanged during a vehicular collision. Given vehicle impact speed and angle KEMM determines the amount of energy received by the human occupants and the likelihood that that energy will cause serious injury or death. KEMM quantified the probability of a fatal or serious injury outcome for the existing geometries of the problematic intersections as well as several alternatives. KEMM also tested the sensitivity of impact speed. The results showed which intersection geometries performed better with respect to risk, and which intersection geometries or treatments can be Safe System compliant. CRISP then sponsored a workshop for local transportation engineers to assess the feasibility of Safe System compliant treatments on the problematic intersections. There was strong interest in many of the treatments, including some innovative and previously untested treatments provided by the MUARC team. One surprising result from the workshop was the reluctance of local engineers to favour reduced speed limits or platform intersections, despite their relatively low implementation cost and strong safety benefits.