Austroads has published an updated edition of Guide to Traffic Management Part 2: Traffic Theory. The Guide provides practitioners with the theoretical background needed to appreciate the nature of traffic behaviour, and to undertake analyses required to develop and assess traffic management plans and road design proposals. The 2015 edition includes a number of significant updates. A new section is provided on the Kinemetic wave model. The kinematic model assumes that high density traffic will behave like a continuous fluid and is also called a continuum model. The model considers the traffic process in time and space, which is more suitable for high density conditions and therefore has its place in analysing flow breakdowns. New supplementary material is provided on an alternative method of calculating delay in gap acceptance situations. Gap acceptance theory is commonly used in the analysis of uncontrolled intersections and defines the extent drivers will be able to use a gap of particular size or duration. A new section on congestion management theory reflects the latest Austroads research findings regarding freeway flow under congested conditions. This area of traffic management has been given increased attention by transport professionals. Much of the theory underlying the developing approaches to flow management is not new but draws on the established relationships of traffic flow. However, using different ways of viewing key traffic characteristics, particularly density, researchers and traffic managers have been able to gain new insights into freeway performance and guidance on how that performance can be improved. Austroads recent research work on ramp metering, variable speed limits and other managed motorway tools is provided in a new section Principles Underlying Managed Motorways. The management of motorways under congested flow conditions is a relatively new focus for road agencies. The new section provides guidance on: - the causes and impacts of flow breakdowns
- motorway operational capacity
- merge capacity for a managed motorway with ramp signals
- the theory underlying variable speed limits.
The new content was prepared by Clarissa Han, James Luk and Kaveh Bevrani from ARRB Group. Dave Landmark, Main Roads Western Australia, project managed the update. The PDF version of Part 2 is $61.60 to download. Hard copies are $77 + postage and handling. Austroads members can download all PDF versions of the Guides for free. This includes all state and territory road agencies and local
councils in Australia and New Zealand. To request your user login and password for free access please send an email from your work email address to austroads@austroads.com.au.
|