The purpose of this paper is to discuss a project that was undertaken to develop standard specifications and test methods for the measurement of pavement roughness, pavement rutting, pavement surface macro-texture, pavement deflection measured with a Falling Weight Deflectometer (FWD) and pavement deflection measured with a deflectograph. No nationally adopted procedures exist for the collection of data and the validation of test equipment in Australia. Pavement condition surveys collect data for pavement attributes including roughness, rutting, strength, skid resistance, cracking and texture, all of which are used for the purposes of monitoring and predicting the performance of the network, determining the timing and selection of appropriate intervention treatments, and monitoring the performance of maintenance contractors. The paper also discusses how the specifications and test methods can be incorporated into contract documentation and makes recommendations regarding future areas of work identified during the course of the project.

This paper summarises the findings of an Austroads/AAPA-sponsored accelerated loading trial conducted to examine the fatigue performance of asphalt mixes. Although over 500,000 cycles of the ALF 80 kN dual-wheel load were applied to four test sites during two stages of testing, no fatigue failure could be induced in any section, with the only distress observed being surface deformation related to shear failure of the underlying unbound base and sub-base layers. The results of an extensive series of response-to-load testing using H-bar strain gauges were also inconclusive because, whilst the effect of temperature on asphalt strain was clearly demonstrated, the results were counter intuitive in terms of the effect of load magnitude and type, and loading rate, on pavement response. Unfortunately the usefulness of the strain gauge data was severely limited because of the large corrections that needed to be applied to take account of variations in pavement temperature. An extensive series of laboratory testing was also undertaken on both laboratory-prepared samples and field specimens and the results are also summarised in the paper. Following the completion of the trial, the performance data were evaluated, along with data obtained from other accelerated loading trials and in-service field trials, to assess whether an asphalt fatigue shift factor should be adopted in the Austroads pavement design system. A number of trials were evaluated, including a recent trial conducted in the USA and the OECD DIVINE Project. The results were inconclusive in that some studies supported the introduction of shift factors whilst others did not.

This report presents the results of an Austroads/industry-sponsored field and laboratory assessment of the performance of an unbound marginal sandstone material and the same material after it was stabilised insitu with bitumen/GP cement and granulated slag/hydrated lime blends. During the trial, nine field experiments were conducted under accelerated loading using the ALF, and about 600,000 cycles of both the 80 kN dual-wheel and 50 kN single-wheel loading were applied. This testing was supported by an extensive laboratory program conducted on pre-construction materials, samples collected during construction, and field cores. It was found that the modulus of both the bitumen/cement and slag/lime cores varied over the site and there was generally no clear difference between the trafficked and untrafficked sections of the pavement. A comparison of the relationship between resilient modulus and UCS of the bitumen/cement stabilised cores at the completion of trafficking with the relationships currently recommended by Austroads confirmed that the current relationships over-estimate the moduli of these materials. In general, the performance of both the bitumen/cement and slag/lime materials was satisfactory, with no fatigue cracking or subgrade deformation observed. The increased costs associated with the stabilisation of the unbound sandstone material with both binders were more than offset by the observed improvement in performance resulting from this stabilisation process. (a)

This report presents the results of an Austroads/industry-sponsored field and laboratory assessment of the performance of an unbound marginal sandstone material and the same material after it was stabilised insitu with bitumen/GP cement and granulated slag/hydrated lime blends. During the trial, nine field experiments were conducted under accelerated loading using the ALF, and about 600,000 cycles of both the 80 kN dual-wheel and 50 kN single-wheel loading were applied. This testing was supported by an extensive laboratory program conducted on pre-construction materials, samples collected during construction, and field cores. It was found that the modulus of both the bitumen/cement and slag/lime cores varied over the site and there was generally no clear difference between the trafficked and untrafficked sections of the pavement. A comparison of the relationship between resilient modulus and UCS of the bitumen/cement stabilised cores at the completion of trafficking with the relationships currently recommended by Austroads confirmed that the current relationships over-estimate the moduli of these materials. In general, the performance of both the bitumen/cement and slag/lime materials was satisfactory, with no fatigue cracking or subgrade deformation observed. The increased costs associated with the stabilisation of the unbound sandstone material with both binders were more than offset by the observed improvement in performance resulting from this stabilisation process. (a)

The AUSTROADS Pavement Research Group and the Australian Asphalt Pavement Association agreed to support an accelerated loading field trial using the accelerated loading facility (ALF) to determine if newly developed test equipment and procedures could produce asphalt mixes with improved resistance to rutting. An extensive laboratory evaluation program was also undertaken for comparison of the predicted results with those observed under ALF loading. The results of the field trial and the laboratory tests, and their relationship, are presented.