Alberta recycles used tires into more rubber roadsThis year, Alberta is using 100,000 recycled tires to pave 13 test sections of provincial roads with asphalt rubber, for a total length of 30 kilometres. The paving, carried out on sections of urban and secondary roads as well as provincial highways, is part of a pilot project underway since 2002 to determine whether asphalt rubber is viable for Alberta. This year's projects bring the total length of road surface paved with asphalt rubber pavement to more than 50 kilometres since 2002.
Alberta is the only province in Canada actively testing asphalt rubber on its roads and highways. The compound is a mixture of traditional asphalt, recycled tire crumb and aggregate. To create asphalt rubber pavement, recycled rubber crumb, one to two millimetres in diameter, is added to the asphalt cement then mixed with gravel to make the pavement.
This type of asphalt is resistant to cracking and rutting, which are concerns on Alberta roads. While the test sections have been found to reduce road noise significantly, results are mixed in the area of cracking and surface condition. One of the biggest challenges to asphalt rubber is Alberta's harsh winters and its high number of freeze-thaw days during the spring; these freeze-thaw cycles place considerable stress on the pavement.
Asphalt rubber pavement has been used in various ways by several countries over the last 15 years. Ten countries regularly use it, and in North America, Arizona has paved more than 4,000 kilometres of asphalt rubber since 1998, while California has used asphalt rubber pavement since 1984.
In the long term, these pavements are known to have a longer life than traditional asphalt and require less repair work because of their greater resistance to cracking and rutting. In addition to reducing road noise, rubber crumb pavement provides better traction and costs less to maintain.
Since 1993, 30 million scrap tires have been recycled through Alberta's tire recycling program. The Alberta Recycling Management Authority of Alberta, which oversees this program, continually investigates new products and effective uses and products from recycled tires. Over 80% of the rubber material currently being recycled is used within the province; this is twice as much as two years ago. No tires have been burned as fuel in Alberta since 1995.
The 2004 asphalt rubber paving project also marks the first year that the equipment used to create asphalt rubber has been provided by an Edmonton-based company, Fath Industries. This enabled the asphalt rubber projects to be carried out more efficiently and reliably. In past years, the equipment used to make asphalt rubber had to be imported from Arizona, which often caused delays and inflexibility for the Alberta projects.
Behind every asphalt rubber project in Alberta is the Alberta Asphalt Rubber Steering Committee. The only committee of its kind in North America, it includes representatives from provincial and municipal governments, industry, and academia. Its members come from: the Alberta Recycling Management Authority, EBA Engineering, Alberta Transportation, the University of Alberta, the cities of Edmonton and Calgary, Strathcona County, Husky Energy and the Alberta Roadbuilders and Heavy Construction Association.
More information is available from Doug Wright of the Alberta Recycling Management Authority, 780/990-1111.