WORKING ON
THE WIMMERA
WHEN TASKED WITH RE-SEALING A SECTION OF THE WIMMERA HIGHWAY IN VICTORIA, RICH RIVER ASPHALT TEAMED UP WITH ROAD MAINTENANCE TO TRIAL ITS NEW BINDER, FEATURING RECYCLED PLASTIC AND RUBBER.
R
ich River Asphalt is an asphalt manufacturer, supplier and contractor that services the Echuca and Moama area, on the border of Victoria and NSW. In 2019, Rich River was faced with the task of spray sealing approximately 850 metres of the Wimmera Highway. The Department of Transport requirements for this section of the road was for a High Stress Seal (HSS) which uses a polymer. In order to get good coverage of the existing modified binder and to prevent reflective cracking, a 14-milimetre HSS seal was applied on top of the existing
10-milimetre primer seal. At the same time the team at Road Maintenance, an asphalt pavement crack seal and spray seal specialist, was developing a new HSS binder called B08, which includes 2.4 per cent waste plastic and 23 per cent recycled tyre rubber. Road Maintenance has been using crumb rubber in its crack and spray seal binders for decades. However, as the industry has evolved to implement other recycled products, the company wanted to investigate what else was possible. The B08 seal on the Wimmera Highway was the starting point for the
Road Maintenance surface texture results for the spray seal surface on the Wimmera Highway: B08 Surface Texture results • The OWP results ranged from 2.2mm to 2.7mm. • The IWP results ranged from 2.2mm to 2.9mm. • The BWP results ranged from 2.7mm to 3.5mm. • The CL results ranged from 1.8mm to 2.0mm (Binder Overlap). S35E Surface Texture results. • The OWP results ranged from 2.8mm to 2.9mm. • The IWP results ranged from 2.7mm to 2.9mm. • The BWP results ranged from 3.5mm to 3.7mm. • The CL results ranged from 2.5mm to 2.7mm (Binder Overlap).
Image of the Wimmera Highway before the B08 seal.
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ROADS AUGUST 2020
development of Road Maintenance’s B08 series called Maxi-Cycle, a polymer modified bitumen range using recycled crumb rubber and recycled plastics. Max Fitzgerald, Road Maintenance Owner, says he has received a lot of interest in this recycled plastic and crumb rubber product and he is excited to be trialling it. For the trial, Rich River Asphalt sprayed a commonly used binder on 450 lineal metres of the road and then Road Maintenance’s BO8 mix was sprayed to cover the remaining 400 metres. Ray Lykles, Asphalt Manager at Rich River Asphalt, says the company decided to use B08 as a result of the push in industry to produce sustainable products that use recycled materials. Incentives such as the Recycled First policy in Victoria, are clear indicators that contractors and government are working towards a circular economy. “We haven’t heard of anyone with a binder that mixes recycled plastic and tyre rubber before, it has been used in some asphalt mixes but we haven’t seen it used for spray sealing, so we wanted to get involved and trial the product,” Mr. Lykles says. He says there was not much difference in the process to spray seal using the B08 binder, however it did become quite viscous on site. The spray sealing works were based five hours away from where Road Maintenance homogenises the binder and it was temperature controlled on the way to site. The product was then loaded into trucks at 190 degrees Celsius at the depot and then further heating was required on arrival to bring the binder up to 200 degrees. “There was a challenge to load the B08 material into the sprayer as it did become quite viscous, so the product was hard to
