A workers’ union is sounding the alarm after cracking was discovered in Louis-Hippolyte-La Fontaine Tunnel’s newly poured concrete.
“When you see something crack, rarely does it stop cracking,” said Philippe-Michel Lang, who is responsible for prevention and worker safety with the union, Conseil provincial du Québec des métiers de la construction.
His union represents about 25 per cent of the tunnel renovation project’s workforce, including all trades from labourers to team management. But, he said, it’s not just his union that is seeing deficiencies and cracking in the tunnel, which connects Montreal to its South Shore.
“We’ve known for several months that these cracks are unusual,” said Lang.
“We’ve poured thousands and thousands of metres of concrete in our careers and we’ve never seen a concrete this new with this many cracks. Something unusual is going on, and we want somebody to reassure us.”
Freshly poured concrete can have some small cracking, he said, but workers are seeing walls and ceilings full of cracks, raising concerns about structural integrity. He said site inspectors have told crews the concrete is curing twice as fast as it should. While it normally should take 25 days, it’s taking half that, he said.
Because it is drying so fast, cracks are appearing, said Lang, “but somebody is going to have to do the tests and reassure everybody that the structural integrity is OK.”
In a statement, Ministry of Transport spokesperson Martin Girard says it is normal for cracks to appear in new, fresh concrete.
“These are mainly superficial cracks,” Girard said. “The quality of the work is not compromised by these. Interventions are planned for larger cracks.”
Throughout the renovation process, there is rigorous quality control, the statement says. Inspections are carried out during construction and will be carried out after, he says.
“If deficiencies are detected, they must be corrected by the contractor,” Girard said.
No matter what is going on, the province should not wait to look into the matter as the project is already delayed and over budget, said Pierre Barrieau, a Université de Montréal lecturer in transportation planning and the president of Gris Orange, a public transit consulting service.
Traffic congestion is increasingly worse due to the lane reductions and there have been more collisions than usual, he said. Further delays to this project will not only continue to create traffic snarls, but it will also delay further construction projects in the region, he said.
Noting he is not an engineer, Barrieau said some cracking is normal, but a lot of cracking is not. Independent engineers and chemists need to be called in to study the situation and determine what is leading to the quick curing and cracking, he said.
Cracks in the concrete can allow salt to seep in, leading to rusted rebar and compromising the structure’s integrity, he said. Applying the right sealant is essential to prevent salt infiltration, he said.
If the problem is extensive and the concrete needs to be demolished and repoured, it must be done quickly to stay on schedule, said Barrieau. It wouldn’t be the first time a major project needed to be redone, he said, citing the recent repaving of Highway 40 in Montreal’s West End.
In the case of the tunnel, he said it’s important to verify and repair as needed now rather than having to demolish everything and redo it after completion.
“If we had known how much it would have cost, we probably would not have fixed it. We would have replaced it. We’ve passed that point,” he said. “Now, unfortunately, there’s so much money sunk into the project, we have to continue.”