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Christchurch, New Zealand

White G.,Fulton Hogan | White G.,University of The Sunshine Coast
Transportation Geotechnics | Year: 2015

As part of a broader investigation into distress in the asphalt surface layer at a major Australian airport, significant testing was performed on cores taken from both trafficked and un-trafficked zones within two different asphalt mixes. Samples were compared for aggregate orientation, relative density, resilient modulus, wheel tracking, interface shear resistance and cyclic shear creep. There was a significant difference between the results from the trafficked and un-trafficked samples. It appeared that the changes to the asphalt caused by 'straight-through' aircraft trafficking increased the asphalt surface's resistance to the severe shear forces induced by heavy braking and cornering of aircraft. It is suggested that where operationally practical, the surface should be exposed to frequent and heavy straight-through traffic for as long as possible prior to allowing harsh braking and turning operations. This would reduce the risk of early life horizontal deformations occurring in the heavy braking zones. © 2014 Elsevier Ltd. Source

White G.,Fulton Hogan
Road and Transport Research | Year: 2015

Bitumen supplies into Australia have become more diverse as importation of bitumen has become common and Australian refineries have been closed or reduced in their capacity. The products on which empirical links between bitumen properties and field performance were established are likely to have changed over the years. This has undermined the effectiveness of the empirical bitumen specifications used in Australia. Similar experiences in New Zealand and South Africa prompted the introduction of performance-based testing. In the USA, the multiple stress creep recovery (MSCR) test was developed as a high-temperature performance grading criterion. The MSCR test is performed using a dynamic shear rheometer. A number of these devices are already available in Australia. The test is simple and takes about 15 minutes to complete. The MSCR test was adopted by the USA for high temperature performance grading of binders because of its advantages over the traditional |G∗|/sin δ. The MSCR was used to evaluate three samples of multigrade M1000 bitumen retained from a number of airport overlays. The M1000 samples assessed were found to be unsuitable at 76°C but suited to very heavy and extreme traffic loadings at 70°C and 64°C respectively. The MSCR testing of binders is recommended for high shear stress asphalt applications, such as airport surfaces. Source

Marradi A.,University of Pisa | Costello S.B.,University of Auckland | Salt G.,Tonkin and Taylor | Frobel T.,Fulton Hogan | Wormald S.,Dynatest
7th International Conference on Maintenance and Rehabilitation of Pavements and Technological Control, MAIREPAV 2012 | Year: 2012

Rapid, low cost evaluation of the stiffness achieved is an important consideration in the quality control of pavement construction. Traditional devices for the measurement of pavement stiffness, namely the Falling Weight Deflectometer (FWD) and the Benkelman Beam, are intended for multiple purposes (network asset evaluation, rehabilitation design and construction quality control), and collect more data than is always necessary for the targeted quality control of unbound pavement layers. Consequently, considerable effort is being devoted to the development of rapid portable pavement structural evaluation tools, in particular tools that measure fundamental engineering properties as opposed to empirical measures. In this study the performance of the Light Weight Deflectometer (LWD) is compared to the FWD for the measurement of stiffness, and to the Nuclear Density Gauge (NDG) for compaction control. Given that the majority of pavements in New Zealand are unbound granular pavements with a chipseal surface, the importance of compaction control of unbound layers is paramount if design stiffness is to be achieved and variability is to be controlled. Source

Alabaster D.,NZ Transport Agency | Herrington P.,Opus Research | Waters J.,Fulton Hogan
Asphalt Pavements - Proceedings of the International Conference on Asphalt Pavements, ISAP 2014 | Year: 2014

The NZ Transport Agency's (NZTA) has been developing an epoxy- modified Open-Graded Porous Asphalt (OGPA) with the aim of creating a low-maintenance long-life (>30 years) low noise surfacing material. The New Zealand laboratory studies and field trials form part of a larger collaborative research programme conducted under the auspices of the OECD/ECMT (European Conference of Ministers of Transport) Joint Transport Research Centre, focused on the economic evaluation of long-life pavements. Investigations into the cohesive properties and oxidation resistance of an acid-cured, epoxy-modified OGPA were undertaken in the laboratory. The initial trials at the NZTA's Canterbury Accelerated Pavement Testing Indoor Facility (CAPTIF) demonstrated the practicality of the project. A field trial constructed on State Highway 1 in Christchurch in December 2007 demonstrated that full-scale manufacture and construction using the epoxy OGPA, could be undertaken without any significant modification to plant or operating procedures in a normal surfacing operation. The trial has been in place for 6 years and is performing well. The original 2007 work has been optimised for cost, manufacture and construction. Test sections were placed on the Christchurch Southern Motorway in 2012 and this paper reports the optimisation and findings on manufacture and construction of the 2012 test sections. © 2014 Taylor & Francis Group, London. Source

Gonzalez A.,University for Development | Cubrinovski M.,University of Canterbury | Pidwerbesky B.,Fulton Hogan | Alabaster D.,New Zealand Transport Agency
Road and Transport Research | Year: 2012

An accelerated full-scale experiment on foamed bitumen (FB) pavements was conducted at the Canterbury Accelerated Pavement Testing Indoor Facility (CAPTIF) in New Zealand. The results of the CAPTIF experiment showed that the section with 2.8% bitumen content and 1% cement content (section B28C10) had the best performance. These results were published in a previous research paper. The current paper is the continuation of the previous work and aims to provide design and performance parameters that could be used by practitioners and researchers. The pavement strains were measured at different depths and transverse locations using pavement instrumentation. The measurements showed that subgrade strains are lower in section B28C10 and that the strain distribution in the subgrade is relatively uniform, reducing the strain concentrations in this layer. Falling Weight Deflectometer (FWD) measurements were used to determine an AASHTO 93 structural coefficient of 0.20 for the FB layer of section B28C10. FWD and pavement strain measurements were used to back-calculate the average elastic modulus of 1100 MPa for the FB layer. Finally, a permanent or plastic strain model was developed for the FB layer using the pavement vertical surface deformation measurements and post-mortem data. Source

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