Demonstration projects for rubberized asphalt in the wintry climate of Alberta has asphalt rubber experts excited over the opportunities those projects could open up for their product.
``The only reason the northern states haven't gone into asphalt rubber is because they claim the technology is only effective in warm climates, such as Arizona,'' said Murray Quance, president of BAS Recycling Inc. in San Bernardino, Calif., and a member of the board of directors of the Rubber Pavements Association. ``If the projects in Alberta are successful, that essentially shoots down their argument.''
Alberta Transportation, the provincial highway agency for the western Canadian province, has collaborated since last year with the Tire Recycling Management Association of Alberta on the project. Between June 27 and July 4, 2002, some 5,900 metric tons of crumb-rubber-modified asphalt paving materials were applied on 4.2 kilometers of two-lane highway in the province's major cities of Edmonton and Calgary, as well as in rural areas of Strathcona County.
``This year, we increased it to 32,000 tons,'' said Al Schulz, a board member of the Tire Recycling Management Association and chairman of its steering committee in asphalt rubber.
``We had more projects in Edmonton and Strathcona County, but instead of Calgary we had a project in Lethbridge, which has a little different climate,'' he added.
In 2004, the metric tonnage of rubberized asphalt used in Alberta highway projects should increase to more than 50,000, according to Allan Kwan, executive director-technical standards at Alberta Transportation.
International Surfacing Systems, a Chandler, Ariz.-based paving contractor that specializes in asphalt rubber, is the contractor in Alberta for the actual asphalt-rubber blend, Mr. Kwan said. But local contractors in Alberta are responsible for combining the rubberized asphalt with gravel to create the ``hot mix'' and actually laying it on the roadbeds.
``Our goal in the first year of the project was to determine whether Alberta contractors could lay down asphalt rubber effectively,'' he said.
``Once we achieved that, in the second year we are working toward achieving better performance-better know-how in the technology to maximize the performance of the product.''
In 2004, when the local contractors are more familiar with asphalt rubber, Alberta Transportation will work on tightening specifications for density, laydown and other factors affecting pavement, according to Mr. Kwan.
With an eye toward achieving that goal, Alberta Transportation has invited two distinguished consultants in rubberized asphalt to visit the province this October, he said. They are George Way of the Arizona Department of Transportation and Jack Van Kirk, a former California Department of Transportation official who now serves as director of asphalt technology with Basic Resources Inc. of West Sacramento, Calif.
Meanwhile, scientists at Arizona State University and elsewhere are evaluating the results of the first two years of the project, according to Mr. Schulz.
Some of the results will be presented at upcoming technical conferences, and a complete summary of the results should be available later this year, he said.