Due to their operational efficiency and low land-take, single-point interchanges (SPIs) are an increasingly attractive option for new or rebuilt interchanges, particularly in more densely developed urban and suburban areas. The authors conducted detailed-design and in-service road safety audits of SPIs, which identified several design elements that are common to SPIs but challenging to road users, including: geometric and sight distance constraints; large intersection areas with unconventional turning paths; safe accommodation of pedestrians and bicyclists; impacts of nearby intersections in urbanized areas; and signal displays and signing. The aim of the work discussed herein is to help highway professionals achieve an enhanced level of safety in the design and operation of SPIs.
Abstract