Ten years ago, the “super-beam” saved the Champlain Bridge

November 2013. The Champlain Bridge threatens to give way. In an emergency and in freezing cold, a 75-ton “super-beam” was installed on the structure, in what had all the appearance of a rescue operation. While the engineering profession is having a hard time, in the wake of the Charbonneau commission, this unprecedented event is making a lasting impression in Greater Montreal. A look back at a high-flying operation, with those who experienced it up close.

“It was truly a mega rescue operation, monitored to the millimeter. And we understood it in hindsight: it created something in the collective imagination of Quebec,” recalls the former communications director of the Société des Ponts Jacques Cartier et Champlain Incorporée (PJCCI), Jean-Vincent Lacroix, who was until recently spokesperson for the Réseau express métropolitain (REM).

At the time, headlines kept coming back to the deteriorating state of the Champlain Bridge. Faced with the emergency, the federal government even ended up announcing in 2011 that it would build new infrastructure, the current Samuel-De Champlain Bridge, inaugurated in June 2019.

Everything changed on November 12, 2013. “I remember: that morning, I arrived and I wondered where everyone was. The office is empty. Then I get a call to join the conference room, where everyone is. We detected a crack in an edge beam of the bridge,” says Mr. Lacroix.

The bridge at this time had seven beams in which the concrete compressed, making it stronger. Instead of installing a complete concrete slab, the engineers chose to install smaller slabs, which were in fact “sandwiched” on top of the beams.

The crack was almost two millimeters wide. Quickly, a traffic lane was closed on the bridge towards the South Shore, as a preventive measure. Then, after extensive analysis revealed that the crack continued to progress, another lane of traffic was closed.

Over time, even if the progression of the crack seemed to slow down, an observation became clear: a structural solution had to be found.

Five days to get there

The “super-beam”, a technological feat, was ordered in 2009 to respond to emergency situations. It therefore emerged as the solution.

Transported by truck, the gigantic assembled piece will finally be installed in just five days, whereas such an intervention normally takes five weeks. Every day, we take stock of the operation, which will culminate on November 30, 2013. “It was almost a television soap opera,” quips the JCCBI construction director at the time, Pascal Villeneuve.

He remembers a “huge challenge”, which had started off with flying colors. “When we arrived there the first evening, then we gave the go to close the lanes and start the work, we realized that the concrete barriers that had to be removed were frozen. It started the weekend a little negatively,” notes Mr. Villeneuve.

“The stress level was really very high,” also recalls the director of the inspection at the time, Mariana Salas. “We had established a very careful plan to monitor the stresses in the concrete and the opening of the crack. But it was very new, this type of monitoring, so we learned on the job. »

Even after installation, “other damage could be expected.” “It was constant. There have been a lot of repairs to the structure so that it survives until the new bridge opens,” emphasizes M.^me Salas, who cites in particular the “crossbows”, these crutches which supported the bridge for years after the installation of the super-beam.

A structural change

Ten years later, the observation is clear: “The industry has learned a lot of lessons from all this,” says the former director of engineering at the SPJCC, Juan Echagüe.

“For me, it was above all the collaboration that was carried out in an emergency that was impressive. Everyone was on the solutions side, everyone was helping each other. It’s something that marked me, which was beautiful to see,” he notes in this regard.

Like his colleagues, he affirms that the success of the operation also greatly contributed to restoring the image of the engineering profession, at a time when Quebec was shaken by several corruption scandals which led to the Charbonneau commission. “It was a time when, in addition, the Champlain Bridge and the Turcot interchange were at the end of their useful life. The reputation of engineers and the industry were under attack from all sides. For us, achieving this was a huge boost of pride,” says Mr. Echagüe.

Pascal Villeneuve is of the same opinion. “It was a sort of wake-up call, a spark plug for the construction of the new bridge, but also for keeping the bridges in place. The following year, JCCBI obtained significant budgets over several years. Budgets before were always annual. And in 2013, it was one of the first times where we had a two-year budget,” he explains.

In 2014, the group finally obtained a five-year budget for the first time, until 2019. “It really allowed us to orchestrate all of the bridge maintenance work much better. […] Today, I think we are more aware of the state of infrastructure. We have really moved from a reactive mode to a planning mode,” concludes Mr. Villeneuve.