VANCOUVER (NEWS1130) – Port Mann Bridge planners insist it was the weather, not the design that led to the ice-fall that damaged several cars yesterday. But at least one expert is questioning the placement of the cables that are directly above the bridge deck.
Christos Georgakis, a structural engineering expert from Denmark, says the designers should have done a risk assessment before the bridge was built to determine whether icefall was going to be a problem.
“If they found that the level was very low, they probably wouldn’t do anything about it,” says Georgakis. “But if they found the level was high, then I would say this not the best choice for the cable planes. They should have chosen vertical cable planes or outwardly-lying cable planes.”
He adds he doesn’t know whether the designers were forced to work with a preliminary design that they weren’t allowed to deviate from.
Mike Proudfoot, CEO of the Transportation Investment Corporation, says specialists are reviewing whether a heating system would prevent snow and ice from accumulating on the cables.
Georgakis, who has researched various de-icing methods, says he hasn’t seen anything on the market that would make sense for the Port Mann Bridge.
“None of them are fail-proof and some of them are probably not worth implementing due to cost,” he explains. “In other places around the world, normally… instead of de-icing, the bridge is shut down until it is safe.”
Earlier this year, the Tacoma Narrows Bridge was also shut down for several hours because ice was falling onto the bridge deck from the cables above. No one was hurt.