Austroads project – Long Term Pavement Performance (AT1064)

Austroads has funded the monitoring of the structural and functional performance of in-service pavement test sections across Australia since 1994/95.  These long term pavement performance (LTPP) test sections fall within the following groups: (1) the US Strategic Highway Research Program (SHRP-LTPP) sites that were set up specifically to be in line with the US SHRP (now referred to as US-LTPP); (2) sites established in tandem with past accelerated pavement testing trials (ALF-LTPP); (3) sites focussing on the effect of different maintenance treatments and practices (LTPPM); and (4) some heavy-duty asphalt pavements established in association with the Australian Asphalt Pavement Association (AAPA-LTPP). 

The LTPP study currently monitors the performance of more than 35 sealed granular, asphalt and concrete pavement sections under different climate and traffic loading regimes.

It has also been recognised that, in order to obtain a broad set of data, representative of the various pavements, climatic conditions and traffic loadings present in Australia, this data-set will need to be augmented.  To achieve this augmentation the following two initiatives were undertaken:

(1)  The applicability of the data available from the United States SHRP monitoring sites (US-LTPP) was assessed in terms of its relevance to Australian conditions.  It was recommended that further investigation of 26 US-LTPP sites be considered in the future work program of the Australian project because they had a comparable rate of pavement deterioration similar pavement composition, traffic loading and climate to the Australian sites.

(2)  Member authorities have been monitoring the long term performance of various pavement types for many years.  A study was undertaken to analyse the performance history of these pavement types in order to identify suitable sealed granular sites for inclusion in the LTPP project.  In response to a request for this data, member authorities have supplied inventory and performance history data such as roughness, rutting, cracking and deflection as well as maintenance data and other related information.  A review and analysis of this data was undertaken to identify any new sealed granular pavement sites that could supplement the data currently monitored by the LTPP project.

Analysis of the data obtained from this project is contained in two publications which are available for download; Refinement of Road Deterioration Models for Australasia and Interim Works Effects Models