Ultra-Thin Bonded Wearing Course Paving Is off to a Flying Start in North America
Cost-Efficient and Eco-Friendly
Asphalt Paving Professionals from Arizona Place Their Trust in Wirtgen Group Technology
The paving of ultra-thin bonded wearing courses is particularly efficient and cost effective with Wirtgen Group machines. As was also seen in Gilbert, Arizona. Here, Sunland Asphalt & Construction, LLC, rehabilitated an almost 13-kilometer stretch of road with the latest Wirtgen technology. The company is one of the pioneers of this construction method in the USA and operates an ideally equipped fleet of machines including a W 220 Fi and a SUPER 1800-3i SprayJet that enable high-precision paving results.
A Pioneer of Ultra-Thin Bonded Wearing Course Paving
Since 1979, Sunland Asphalt & Construction has earned itself an outstanding reputation as a specialist for paving high-quality asphalt surfaces with a multitude of projects ranging from extremely challenging highways to racetracks. Delivering top quality is the guiding principle in everything they do. On rehabilitation projects over the past ten years, Sunland Asphalt & Construction has concentrated more and more on the paving of ultra-thin bonded wearing courses for road maintenance and are today among the few companies in the United States who carry out this cost-effective and sustainable construction method. In this method, the Vögele SUPER 1800-3i SprayJet paver sprays a tack coat of polymer-modified bitumen emulsion onto the existing pavement or the removed surface layer to seal the base. It then paves a thin asphalt surface layer over the top of this coating, all in the same pass. Sunland also makes use of this cost-efficient solution in the US State of Arizona.
What is Ultra-Thin Bonded Wearing Course Paving?
The ultra-thin bonded wearing course paving method is generally used for the rehabilitation of roads in need of repair, but can also be used for laying down a surface layer on newly paved asphalt. In this method, a paver with a spraying system applies a film of binding agent that completely seals the lower layer before paving a new surface layer over the top of it, all in a single pass. There are significant advantages to working in a single pass: The binding agent film cannot be inadvertently driven over and damaged by other construction vehicles. The binding agent film seals the entire lower layer and provides an effective barrier against water. The new asphalt layer is only half as thick as in conventional road construction. This means up to 50% lower material costs and a simultaneous reduction of the time required for paving.
All the advantages at a glance:
In Gilbert, not far from the city of Phoenix, Arizona, Sunland Asphalt rehabilitated an almost 13-kilometer stretch of the Higley Road with machines from the Wirtgen Group. The project involved the removal of the existing wearing course followed by the paving of a new asphalt surface layer. “We began by milling off a ¾ in (1.9 cm) pavement layer with our W 220 Fi. Right after this, we followed on by spraying a binding agent on the mat with the SUPER 1800-3i Sprayjet and paving over this with an ultra-thin bonded wearing course with a thickness of one-inch (2.5 cm) in a single pass,” reports Joseph Knight, Project Manager at Sunland Asphalt. “The method is not only cleaner and greener, it’s also nowhere near as messy as conventional asphalt paving.”
“The construction process is cleaner and greener.”
Joseph Knight, Project Manager at Sunland Asphalt
A Wirtgen Cold Milling Machine and a Vögele Spray Paver Raise Quality to an Entirely New Level
Sunland Asphalt has been relying on machines from the Wirtgen Group for years. The Wirtgen W 220 Fi and the Vögele SUPER 1800-3i SprayJet paver were added to the company fleet only six months ago and the handling was still relatively new to the team. It quickly became clear that they were nevertheless the right choice for the project in Gilbert: “These Wirtgen Group machines are incredibly user-friendly,” reports machine operator Kolbe Mahkewa. “The controls are all easy to use on the job and are actually just as self-explanatory as the overall operating concept. The software is very useful, too. It provides everything you need at the press of a button.”
Thanks to its excellent milling performance, the W 220 Fi delivered an even, high-quality surface – the ideal basis for the paving of thin asphalt layers.
Maximizing Synergies
In Gilbert, Sunland Asphalt benefited from perfectly coordinated technologies from the Wirtgen Group: from the cold milling machine and the spray paver to the tandem rollers used on the project. These all make the method particularly efficient.
