$5-million project launched to solve pyrrhotite problem in Quebec concrete
A multi-million dollar research project is being launched to learn more about pyrrhotite, a mineral found in some forms of concrete and which is blamed for damaging thousands of structures in Quebec.
Pyrrhotite expands when exposed to humidity and oxygen, and its presence can cause cracks to a building's foundation.
The research project will work to determine at what concentration pyrrhotite starts causing problems for buildings. It will also explore better detection methods and how to prevent pyrrhotite from being mixed into concrete during a building's construction.
Through Canada's National Research Council (NRC), a research chair based in Université Laval's faculty of science and engineering has been created to develop solutions over the next four years.
The federal government is contributing $4 million of the project's $4.9-million budget; the Quebec government is funding the rest.
The province has already pledged $52 million to compensate homeowners affected by damage caused by pyrrhotite.
It has wreaked havoc on the foundations of thousands of homes and commercial buildings in the Mauricie and Central Quebec regions that were built between 1996 and 2008 with aggregate from a local quarry.
"We cannot live here in the Mauricie without knowing someone touched by pyrrhotite," François-Philippe Champagne, the federal minister responsible for infrastructure, said at a news conference announcing the project.
He said the damage from pyrrhotite can be so costly it has driven some property owners into bankruptcy.
"We want to put science in the service of victims," he said.
Josée Duchesne, one of the research project's two co-chairs at Université Laval, said they have made significant advances in research into pyrrhotite since 2010, and have promising leads to follow over the next four years.
Geology and geological engineering professors, as well as NRC scientists, will develop tests to figure out the right amount of sulfides, such as pyrrhotite, that concrete can hold without cracking.
"For future concrete construction, we expect no more problems with pyrrhotite," Duchesne said.
