Recycled Glass Bridges Win ACI Award
Last month, Canada’s Darwin Bridges won first place in the Infrastructure category of the American Concrete Institute’s Excellence in Concrete Construction Awards. The twin bridges previously won the 2021 Award of Excellence in the same category from the ACI’s Quebec and Eastern Ontario chapter, which nominated them for the International award.
The bridges are reportedly the world’s first bridges built from concrete made with 10% of recycled glass powder. According to the City of Montreal, the glass powder and concrete mixture increases the predicted lifespan of the bridges from 75 to 125 years, combined with its corrosion-resistant stainless-steel rebar.
Darwin Bridge Construction
In October 2020, officials working on the Darwin bridge project on Nun’s Island in Montreal, Canada, reported that the structure would incorporate recycled glass in its materials.
While recycled glass has been used in the City of Montreal for concrete-based sidewalks and store floors, the city reported that the bridge is the first in the world to use the recycled material for this form of infrastructure.
In following a pilot project conducted in partnership with the SAQ and the Université de Sherbrooke, researchers landed on the idea that using powdered recovered glass in a road bridge is just the latest in how the material can be advanced.
Marie-Hélène Lagacé, SAQ Vice President, Public Affairs, reported that the new use in construction arrives after more than 15 years of research and development by the partnership, in searching for new methods to use the glass bottles it sells.
Not only did the recycling option help the company itself, but also helped local landfills, which had been reportedly overflowing with recycled materials such as glass.
According to lead design engineer on the Darwin bridge project, Étienne Cantin Bellemare, an estimated 70,000 recycled glass were ground into a fine white power and accounted for 10% of the material used, saving roughly 40,000 kilograms (about 88,185 pounds) of cement.
Construction on the eastbound lane was slated for completion by the winter, with both lanes expected to open by this fall. Bellemare added that officials will be studying the structure and how it performs over the next few years following completion.
If the use of recycled materials proves successful, they expect recycled glass will be used in more infrastructure projects throughout the world.
Other ACI Awards
The ACI recognized 14 winners at the seventh annual award ceremony during the ACI Virtual Concrete Convention on Oct. 18. According to the ACI, the Excellence in Concrete Construction Awards “celebrate innovation and inspire excellence throughout the global concrete design and construction community.”
The Overall Excellence award was presented to Aldilonda promenade around Bastia fortress, located in Corse-du-Sud, France. The concrete pathway acts as a balcony over the coastline, allowing pedestrians and cyclists access to a closer view, and connects the city’s north and south parts via tunnel constructed from board-formed architectural concrete.