The twin Darwin bridges, which are located on Boulevard de l’Île-des-Sœurs in Verdun, have been completely rebuilt using concrete containing 10 per cent recycled glass powder, making this innovative achievement a world first.
A world premiere: Concrete containing recycled glass powder
These are the world’s first bridges built with concrete containing finely ground recycled glass powder. This innovation is the result of 17 years of research at the University of Sherbrooke.
Cement production is a major source of greenhouse gases. Replacing 10 per cent of the cement with recycled glass powder resulted in:
- Recycling the equivalent of 70,000 wine bottles.
- Using 40,000 kg less cement, (about 1,400 30 kg bags).
- Reducing CO2 emissions by 40 tonnes (the amount of CO2 produced by a car travelling 200,000 km).
A longer service life
The use of glass powder to replace part of the cement makes the concrete more impermeable, resistant and durable. Combined with corrosion-resistant stainless-steel rebar, the glass powder/concrete mixture increases the predicted life span of the two bridges from 75 to 125 years.
Two prestigious awards for this ground-breaking project
The American Concrete Institute - Quebec and Eastern Ontario Chapter - gave the project its 2021 Award of Excellence winner in the Infrastructure category and submitted it to the ACI international organization, which awarded it the prestigious 2021 Award of Excellence in the Infrastructure category.
Two major partners collaborated with the city in this pilot project: The SAQ, and the SAQ Research Chair in Glass Recovery in Materials at the University of Sherbrooke.