Passenger car equivalence shows higher efficiency from B-doubles than semi-trailers on an urban motorway

摘要

Multi-combination vehicles (MCVs) in urban areas are known to impact on productivity, safety, infrastructure wear, congestion and the environment. As the size of the heavy vehicle fleet is growing (ABS 1972-2001), it can be assumed that freight operators are experiencing greater efficiency in larger vehicles. How do these larger vehicles influence road capacity, the number of movements required and ultimately the operating characteristics of roads? ududA testing program was undertaken to observe passenger car behaviour around MCVs in a longitudinal sense. Video footage was collected on a four lane divided mainline motorway section that provides access to the Port of Brisbane, Australia. This section was level, straight and away from ramp junctions. It experiences high traffic volumes with a one-way AADT of approximately 33,500. The percentage of class 4 heavy vehicles, which includes semi-trailers and B-Doubles, is 6.7%. The route is currently designated for B-doubles, which is the most common MCV in Australian urban areas. ududThe research showed for the facility and conditions tested that even though the passenger car equivalent (PCE) is 15% higher for a B-double than a prime mover semi-trailer combination, B-doubles are still more road efficient as they carry more freight. ududA better appreciation of PCEs of these vehicles would aid road authorities in quantifying the longitudinal behavioural impacts.