Ice falling from CN Tower caused minor damage to Rogers Centre: engineer

Risk of falling ice still a concern near CN Tower For a third straight day, the CN Tower has been closed due to concerns about ice falling from the top of the structure onto sidewalks below.

The original structural engineer of the Rogers Centre said the hole in the stadium’s retractable roof caused by falling ice after a weekend ice storm was relatively minor.

“It’s not surprising that something like this would have happened,” Michael Allen, the president of Adjeleian Allen Rubeli Ltd., a structural engineering firm, told CTV News Channel on Tuesday.

“There has been ice coming from the CN Tower before and damaging the roof’s membrane,” he said. While this is the first time that ice has actually penetrated the steel deck supporting the roof, the important thing is that the damage did not lead to “a progressive collapse,” he said.

Monday’s scheduled Major League Baseball game between the Toronto Blue Jays and the Kansas City Royals was postponed after chunks of ice fell from the CN Tower, smashing through the roof of the stadium and creating a car-sized hole in right field.

It was the first time that a game was postponed at the Rogers Centre in 17 years. In April 2001, two of the roof’s panels slammed into each other during routine testing of the retractable roof, creating a hole.

When the 52,000-seat Rogers Centre, then called the SkyDome, opened in 1989, it boasted the first retractable stadium roof in North America.

Allen said that his team of engineers was acutely concerned about damage to the roof from “something falling from the sky,” particularly because of the stadium’s location in the downtown core of Toronto and its proximity to major airports—so much so that it ran computer modelling of that scenario.

“We imagined that we had a 9-metre diameter hole through a critical part of the roof,” he said. "We modelled that severe condition, ran the analysis and determined that the roof would be safe.”

A number of workers braved the elements to repair the hole on Monday.