Concrete pavements in Western Australia
In many parts of the world concrete (rigid) pavements have been proven to provide a longer pavement life with less maintenance and rehabilitation requirements than flexible pavements surfaced with asphalt and seals. Though commonly adopted in some Eastern Australian states, they represent only a small portion of the road network in Western Australia (WA). The aim of this article is to summarise the locations where concrete pavements are already in use in WA and to highlight some of the design and construction methods used.
Historically in WA, pavements constructed using concrete have been adopted for problematic causeway locations and components of industrial pavements. Examples of concrete causeways can be found in the Gascoyne, Kimberley and Pilbara Regions. These ‘pavements’ have not been designed following typical concrete pavement design methods; rather structural or slab-on-grade design methods. Likewise the use of concrete pavements for industrial applications is also uncommon. Where they have been adopted the Guide to Industrial Floors and Pavements, design, construction and specification method published by the Cement and Concrete Association of Australia (CCAA) has generally been adopted.
Only recently Main Roads WA has opted to utilise rigid pavements at selected new junctions in the north of the State and in the Perth metropolitan area for sections of pavement that are subjected periodically to saturated conditions. These pavements have been designed following the Austroads Design of Rigid Pavements method with joint detailing and specifications based on New South Wales (NSW) Roads and Maritime Services (RMS) requirements, with local variations. These sections include heavily trafficked junctions where jointed plain concrete pavement (PCP) was adopted as an alternative to traditional granular pavements with thin bituminous surfacings and full depth asphalt pavements in very hot climatic regions (e.g. Dampier Highway Duplication and Great Northern Highway Realignment in Port Hedland); and sections with high water table levels designed with continuously reinforced concrete pavement (CRCP) (Gateway, WA project).
This article outlines the experience with concrete pavements in WA, including design and construction challenges, performance records and maintenance issues. It discusses regional traffic and environmental conditions, as well as locally available materials, explaining how they influenced the pavement design and the adaptation of construction specifications.