Transportation

Ice bombs inevitable

The reason for ice bombs dropping onto vehicles from the $3 Billion Port Mann bridge? Take a look.

Compare the Alex Fraser bridge.

On the new Port Mann, the bridge decks, east and west bound, are shrouded to the outer edges by cables carried from the centre towers. On the Alex Fraser, the cables are on the outside of the bridge deck.

Failure to deal with the predictable ice falls was a serious error. The entirely predictable difficulty was known to bridge design engineers. An Ohio facility had similar problems.

Ice prompts review, ToledoBlade.com, December 13, 2007

“The possibility of ice falling from the Veterans’ Glass City Skyway’s stay cables after winter storms was considered during the bridge’s design but deemed unlikely to occur often enough to justify countermeasures, an Ohio Department of Transportation spokesman said yesterday.

“Now state officials will have to decide if this week’s weather sequence – an ice storm followed a day later by steady rain that sent chunks of ice plunging onto the bridge’s southbound lanes – is as fluky as they thought.

“…The falling ice prompted officials to close two of the three lanes for about six hours Tuesday and was a contributing factor in a collision on the span…”

The engineering school at Dartmouth has a worthwhile webpage offering one possible solution, De-icing the world

“Dartmouth Engineering Professor Victor Petrenko and his research team discovered that applying short pulses of electricity directly to an ice-material interface produces some novel and desirable effects. This discovery led them to invent an ultra-fast and efficient method of ice removal and prevention called pulse electro-thermal de-icing (PETD).

“…Petrenko’s PETD method was also put to the test in Sweden where a 1712-meter-long ‘cable stayed’ bridge is experiencing major problems with icing. The $250 million publicly-funded bridge currently must be closed down for significant periods of time during the winter months due to dangerous chunks of ice falling at random off the towers and cables from heights of up to 140 meters.

“The first tests of PETD on a few cables and one pylon demonstrated instant de-icing action at very low energy consumption as compared with conventional de-icers.”

Wondering about the high cost of the new Port Mann bridge? Read Talking real money here at Northern Insight.

Categories: Transportation

9 replies »

  1. I'm hoping a change in government will involve audits into these projects, and criminal charges for those if there was any kind of corruption and lining of developers' pockets.

    Like

  2. Bad design, by incompetent engineers, this is the story behind the Port Mann Bridge Mk.2

    The BC Liberal government used big transit projects like the Port Mann, the Canada Line, and the Gateway highways projects as massive slush funds to funnel taxpayer monies to corporate Friends of the government.

    Over design and gold-plating of provincial transit projects has lead to:

    – The $3 billion Port Mann Bridge has a serious and potentially design flaw that may lead having shut down in icy and snowy weather.
    – The $2.5 Canada Line, by design to keep the mini-metro from going grossly over budget has a maximum capacity less than a simple streetcar! For the cost of the Canada line, we could have built LRT from downtown Vancouver to Steveston and the airport and a LRT line from BCIT to UBC along Broadway and a LRT line in Surrey!
    – The Gateway highways project is so over designed and gold plated, they are renaming it Hwy 17 and will make Vancouver commutes from those living in Tsawwassen and Vancouver bountravelersrs from BC Ferries longer than the present Hwy 17!

    Like

  3. Swedish bridge only cost $250 million? Ours a cool 13 to 14 times that? Somethings fishy, here. Time for the establishment of a Quebec stype Anti-Corruption Commissin here. Not that there is anything amiss here or for that matter, in Lotus land as a whole…after all, according to the BC Libs, everything is just peachy!
    Job creation news everyday (albeit hard to pin down the numbers), big ticket items to entice the lower mainland (at a huge cost mind you), Chinese labour being brought in,(not enough skilled people for this in Canada eh?), IPP projects to make the taxpayers go broke…Naaa nothing amiss here, is there. Just move along now….

    The BC Liberals are living in “Polly Anna” land, one mess after another. What a crock! The election will definitely be a “defining moment”, for the current “regime”.

    Bring on the Conflict of Intrest hearings, a BC Rail Judicial enquiry, and a Quebec style Anti-Corruption commission. This province needs a “serious” cleansing! Someone or some group has to be held accountable, for this ridiculous form of “governance”!

    Like

  4. Christy may have decided to stay away for a few more weeks when this news broke. “Let me know when the snow's gone and it's sunny and warm.”

    It may have been a perfect storm and won't be a regular occurrence… but I wouldn't count on it.

    It's curious that the old bridge didn't have problems with ice bombs dropping off the crossmembers.

    I'm thinking about highway overpasses and how some railings lean inward to the pedestrian lane. I always thought this was to discourage people from leaning over the edge… but maybe it's also to have the snow bombs fall onto the deck first, rather than onto traffic below. Functional design.

    Like

  5. why bridges in europe cost less than in B.C.? Well follow the money. who got the contracts to build them? Who decided P3s? How are the politicians & senior bureacrats related to the corporations. Its all about follow the money.

    The lieberals couldn't manage money. They & their ilk just like to think they can. Well they do manage money very well. They manage to get most of it for themselves & their friends. They don't care. The taxpayers can pick up the bill.

    When I first read about the ice bombs on the bridge I couldn't stop laughing. I mean it is funny, as in how stupid could the builders of the bridge have been to not factor in the weather. Like it isn't as if we don't get snow & ice & winds & all of that good stuff. Not to mention other bridges had the problem previously. Gees are the lieberals & their friends ever stupid. they can't even get a bridge built without endangering the lives of the drivers & then to add insult to injury, they charge people to cross it! These people need to be fired!

    Like

  6. We need a serious and detailed explanation as to why a bridge in Sweden costs $250 million and our bridge costs 13 – 14 times that amount.

    Like

  7. It's like the Ford Motor Company's exploding fuel tank solution. Ignore it. It's cheaper to pay off for dead and injured people than to fix a faulty design.

    Like

Be on topic and civil. Climate change denial is not welcome. This site uses aggressive spam control. If your comment does not appear, email nrf@in-sights.ca