Ahead of the curve

Legendary golfer Arnold Palmer once remarked: “The road to success is always under construction.” The seven-time major winner never stopped trying to improve his game and is also remembered as an innovator – quick to welcome changes such as making golf attractive to TV audiences.

An appetite for innovation and an attitude of getting it right first time have also worked well for Australasian civil engineering and resource company Fulton Hogan.

The company has more than 80 years’ experience as roading, maintenance and surfacing experts who have developed best practices for producing high-performance pavement structures and road surfaces. It also takes pride in continually looking for ways to do things better.

So when the Australian roading industry, under the banner of Austroads and the Australian Asphalt Pavement Association (AAPA) embarked on a multi-year program to “make EME2 happen in Australia” in 2014, Fulton Hogan came aboard. It was confident it could help launch a change that improves the way roads are made in this country.

Developed in France more than 30 years ago, EME2 asphalt mixes are produced using a hard paving grade bitumen with a higher than normal binder content.

Using EME2 reduces the thickness of full depth asphalt pavements (approximately 20 per cent), lowering construction and maintenance costs, while still providing sound pavement performance through a combination of high modulus (more stiffness), superior fatigue (high elasticity), deformation and moisture resistance.

Queensland has set the benchmark in Australia for successfully adopting the new technology required for using EME2 asphalt.

So far, more than 50,000 tonnes have been laid in the state compared with about 15,000 tonnes in Perth, Sydney and Melbourne where its longer-lasting qualities and other advantages are gradually receiving more recognition.

Fulton Hogan saw the refinement of EME2 for Australian conditions as a chance to maximise the opportunities that come with being a vertically integrated company that offers quarries that supply the aggregate for road construction and the asphalt for the base and wearing courses.

Gympie Arterial Road project impresses judges

Fulton Hogan was recently highly commended in AAPA’s Queensland Awards for successfully using warm mix EME2 asphalt for the Gympie Arterial Road Pavement Rehabilitation Works contract. The busy arterial in the north of Brisbane carries around 75,000 vehicles daily, including a high percentage of heavy vehicles.

At the time (April-May 2017) its upgrade was the largest EME2 mill and fill project in Australia and as close monitoring continues, the high temperatures of the current summer are among tests it has passed with flying colours.

Chris Lange, Technical Manager (Northern Region), says Fulton Hogan was the first company in Australia to use EME2 with warm mix technology. “The positive outcome of this improved process means paving temperatures can be lowered without compromising the performance of the material. This will bring significant energy savings during production and allow for a wider paving window for mill and fill operations.”

While it’s been an undoubted success, it also offered some learnings that are being absorbed and shared with the industry.

Laszlo Petho, Fulton Hogan’s Pavements Manager (Northern Region), says the company’s use of EME2 required a huge commitment to “get things right first time” – the strategy the company adopts for all its work. As part of its commitment to quality, there was a desire to work closely with the client RoadTek, who undertook the administration of the project on behalf of the Department of Transport and Main Roads.

EME2 is not manufactured based on a prescribed composition – it is a mix design where the engineering properties are tested which makes the technology unique. Ensuring the EME2 mix has the qualities that have made it so well regarded in Europe – stiffness, rut resistance, fatigue resistance, and remaining moisture resistant while also being suitable for local conditions – required many months of design and testing at the Fulton Hogan laboratories in Queensland and Sydney.

“During this time it was ensured that the mix had a very good workability to achieve the required compaction levels, without compromising the wheel tracking, stiffness and fatigue performance,” Dr. Petho explains.

Field trial boosts confidence

Testing, and the pooling of knowledge, culminated in a trial where EME2 was laid at a nominal thickness of 100 millimetres on a section of heavily trafficked road using a Pavement Quality Indicator (PQI) meter for monitoring the compaction process.

“Staff were trained and given the tools so they didn’t have to wait till the next day for someone to arrive on site and carry out the core compaction tests,” Mr. Lange says. “With the use of the non-nuclear PQI, you can monitor compaction in real time so they could be confident of a high quality product which conforms to the specification first time.”

Fulton Hogan invited representatives of the client to the trial to provide firsthand feedback so any concerns around the technology, or the manufacturing and paving process, could be resolved quickly. This feedback influenced the Asphalt Quality Plan (APQ) as part of the continuous improvement process and gave both the constructor and client the confidence to proceed.

“As part of the build-up to any project, staff always pre-inspect a job site to assess as a minimum, the base/pavement quality and levels to ensure that they are acceptable to achieve the asphalt quality expected by the client. It was no different on this project,” Mr. Lange says.

Due to the high traffic volume on the Gympie Arterial Road, all the work had to be done at night. The project required removal of the old pavement material and backfilling of two layers with EME2 as a structural layer; the EME2 surface was used for temporary trafficking. Almost three weeks later, the wearing course was laid. “In such an environment it is always a challenge to fit the milling and the paving operation within a short time window, while allowing sufficient time that the freshly laid asphalt cools down before opening to traffic,” Mr. Lange says.

“Without the success of the Gympie Road project, clients in Queensland would not be as confident in EME2 today,” Dr. Petho says. “It has become well regarded very quickly – other road agencies in Australia and New Zealand see its advantages.”

He adds that the client’s feedback has been very positive. “With regard to quality, there were no non-conformances on this job which is a direct result of Fulton Hogan being pro-active on the pre-job preparations by running plant and field trials. We knew exactly what we would be doing when the job started. “We have recently had a project performance feedback from the client. They visited the site and assessed the performance; the pavement structure is holding up very well with no sign of any distress at all. We can be very proud of how it has turned out.”

The use of products such as EME2 builds on Fulton Hogan’s history of its pavement engineers providing alternative innovative solutions with products such as PortPhalt, JetBind and MotoPhalt that are proving their worth in the toughest environments such as ports, airports and motor racing tracks.