New access ramp to Metro Transit garage built with tyre-derived aggregate
“Where the rubber meets the road” has taken on new meaning in Halifax Regional Municipality.
The region, in partnership with the province and Stantec Consulting Ltd. of Dartmouth, used tyre-derived aggregate to build a quarter-kilometre access ramp, the Ragged Lake Transit Access Connector Roadway, linking Highway 103 and a new municipal transit garage.
“It made great sense for this application,” Jim Simmons, a senior environmental engineer with Stantec, said Thursday.
The aggregate, developed by Stantec and integrated into WSP’s roadway design, is manufactured from recycled tyres shredded to precise engineered specifications and used as roadbed, said Simmons.
“The material is buried two metres below the surface.”
He said all scrap tyres in Nova Scotia are recycled as tyre-derived aggregate, which is typically used as structural fill in civil engineering projects.
Tyre-derived aggregate is used in road construction in the United States, Simmons said, but this is the first time it has been used to build a Nova Scotia road.
He said Nova Scotia recycles about 1.2 million tyres a year and 800,000 scrap tyres were used in the Ragged Lake road project.
Simmons said tyre-derived aggregate is cheaper, lighter and more sustainable than traditional fill material.
Municipal design engineer Anne Sherwood said the Ragged Lake project was a great opportunity to use a locally sourced recycled material in a different way.
“Not only is the use of shredded tyres an environmentally friendly and innovative approach to road construction, since they are processed locally, the cost was comparable to traditional fill.”
Halifax C&D Recycling in Goodwood supplied the tyres.
The Resource Recovery Fund Board contracts the recycling company to produce materials meeting specifications for civil engineering projects.
Municipal spokeswoman Jennifer Stairs said the region has no immediate plans to use tyre-derived aggregate in other road construction, but it is looking at different applications for the recycled rubber.
David McCusker, the municipality’s transportation planning manager, said the Ragged Lake connector is the first major section of municipal roadway built for the exclusive use of transit buses.
“When we can get buses out into service more quickly, we’re providing more productive hours and better service for commuters,” he said.
“It may be only a few minutes saved for each bus, but with the number of buses exiting the Ragged Lake Transit Centre, it adds up to almost $100,000 a year in savings.”
Engineers Nova Scotia, which presents the annual Lieutenant Governor’s Award of Excellence in Engineering, gave an honourable mention this year to Stantec and the municipality for their work on the roadway.
Source: The Chronicle Herald
Published: 13 Mar 2014