Repair work nearly complete on Valley Line LRT’s cracked concrete piers, contractor says

Work to repair dozens of cracked concrete piers along Edmonton’s beleaguered Valley Line Southeast LRT is nearly complete, clearing the way for final safety testing on the 13-kilometre line.

At a news conference Tuesday, TransEd CEO Ronald Joncas said 94 per cent of the structural repairs are done on the piers that support elevated sections of track.

“We are at the end of the repair process,” Joncas said.

“The final work includes concrete surface finishing and clean-up which does not impact the testing the of the train.

“In fact, you may see trains operating through the whole alignment, from 102nd Street all the way to Mill Woods, before the new year.” 

Joncas provided no timeline for when the LRT will go into operation but said he remains confident it will be in service soon.

He said, however, that the ongoing testing can not be rushed and TransEd will not compromise on safety. 

“I want to give you an estimate. I will not give you an estimate today,” he told reporters. “You have to consider, at this time of the year, some of these tests will require a little bit more time and we have a third-party certification process.” 

The $1.8-billion public-private partnership between TransEd and the City of Edmonton is two years behind schedule.

The line, which will run between Mill Woods and downtown, was expected to be in service by December 2020 but construction has been delayed several times, most recently by the structural problems discovered this summer. 

In August, TransEd announced that cracks had been discovered in 18 of the 45 concrete piers supporting elevated sections of track. About a month later, three more were added to that tally. By mid-November, TransEd said 30 of 45 piers needed repairs.

An engineering assessment determined that steel reinforcement within the piers was inadequate, resulting in cracks.

Train testing on the elevated sections were suspended as engineers investigated possible fixes.

Train movement along the entire track will allow TransEd to begin the final phase of safety testing, Joncas said.

Line-wide testing and independent safety certification work will begin in January, he said. Lane and road closures will also end early next month, he said. 

Testing will include operational scenarios in partnership with maintenance and operational staff, and determining how the trains will meet surge demand during peak hours and special events, Joncas said.

“We are excited to begin this final line-wide testing and demonstration and safety certification in January,” he said. 

“TransEd is committed, over the coming months, to delivering the Valley Line Southeast in a manner that fully meets the safety service requirements that Edmontonians expect and deserve.” 

Joncas said TransEd will keep Edmontonians and the city informed on new timelines for the project as the final testing work progresses.

He thanked city residents for their “continuous patience” with the project. 

Three methods have been used to strengthen the existing bridge structure. The repairs involve steel reinforcements, added bracing and concrete infill.

Rebar has been drilled and anchored into the existing concrete on some piers. The steel reinforcements will help strengthen the existing steel structure.

External supports are being used on some piers. They are made of steel beams connected by tensioned steel rods. 

Concrete diaphragms were added to some of the compromised piers, providing additional structural support. 

“We have run a thorough analysis on every single one of those piers,” Joncas said.  “We are 100 per cent confident that these piers are fully strengthened to the design requirements.”

As of last week, the last steel beam bolts were being tightened, all the steel beams had been set into place, and all the new concrete diaphragms had been poured.

The project has faced a series of setbacks since TransEd started construction in spring 2016. 

The biggest hurdle came in spring 2018 when crews discovered a car-sized concrete slab nine metres below the surface of the North Saskatchewan River, delaying work on the Tawatinâ Bridge.

Further delays were attributed to a longer-than-expected testing process for the new trains. 

Taxpayers will not be on the hook for any cost overruns for the project. The TransEd consortium, created specifically to build the LRT under the P3 model, is responsible for cost overruns and paying for the mistakes.

“I can tell you, it’s not cheap,” Joncas said. “But we are bearing the costs and I assure you, once again, that will have no impact to Edmontonians.”

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