Road to runway renewal loses its grooves
A new approach to airport pavements in Australia that could reduce maintenance costs and improve the durability of runways could be just around the corner.
University of the Sunshine Coast research student Sean Jamieson will present a potential alternative option at the AAA Pavement Technology Workshop next month. The workshop will also give delegates the opportunity to hear about other industry research and technology standards, along with an international perspective from the FAA.
With the method used to construct runways and airfield pavements remaining largely unchanged in Australia in recent years, Jamieson suggests there’s good potential to improve outcomes with a new approach.
The Royal Australian Air Force airfield engineer was the first person to be seconded to the University of the Sunshine Coast to complete research for the University’s Airport Pavement Research Program.
The Program is supported by the AAA and is addressing a long-term research gap in the Australian pavements industry.
“There hasn’t been centralised research for Australian airports until the program was set up in the last few years,” Jamieson says.
“We use what has been tried and tested for 15-20 years, but now we can improve technologies.”
One of those improvements centre on finding new ways to ensure a runway has enough skid resistance to allow aircraft to take off and land safely.
Runway surfaces need to have either grooves, or 1mm in surface texture or friction levels above minimum requirements to satisfy international and Australian skid resistance regulations. Currently, Australian airports typically satisfy these regulations by applying grooves to runway surfaces.
But Jamieson says this can be costly to maintain, with grooves prone to deteriorating over time and even closing up in some of the country’s hotter climates.
The answer, Jamieson says, could lie in a form of asphalt currently used on Australia’s roads and some overseas runways.
Jamieson has been looking at using stone mastic asphalt (SMA) instead of the dense graded asphalt (DGA) mixtures currently used.
He believes this approach could enable airports to meet international and Australian requirements in terms of surface texture and friction, while removing the need for grooving.
“China has used SMA on over 40 runways. Germany and Norway also have a number of runways surfaced with the material, proving the application for international airports,” Jamieson says.
“We use SMA on roads in Australia and as part of our research we have adapted the mixture for airport applications.
“You have got to make sure the material performs better, or just as well as the current DGA surfacing for it to be suitable as an airport pavement material.”
Trials have been positive, with Jamieson suggesting SMA could ultimately reduce maintenance and replacement costs without compromising the all-important performance and safety requirements.
“Because SMA has a higher course texture, you remove the requirement for grooving, and that could mean a $600,000 to $800,000 saving every time you do a runway overlay.
“It could also lead to up to $200,000 a year savings in depreciation. Because of the binder rich nature of SMA, it generally lasts five to eight years longer than the DGA surfacing used today.
Jamieson says there has been strong interest from airport operators and the Department of Defence, which also maintains and operates airfields.
He believes the key to success will be ensuring people familiar with using SMA are involved in the process.
With laboratory and field tests complete, Jamieson says the results aid in proving the technology’s effectiveness as a runway material.
He will present his research at the Pavement Technology Workshop in Melbourne on 14 May.
The workshop will discuss a range of issues relating to pavement industry standards, including the standardisation of products, testing regimes and quality monitoring. To find out more about the event or to register, click here.