Glad to hear you’re making progress, Muffin! North of Superior is some beautiful scenery.
Good news on the deer front -SGI will pick up the tab for the towing, and the rental car, and will pay the deductible. Apparently " Acts of Deer" count up there with “Acts of God.”
Florida: hanging chads and hanging bridges?
According to the Toronto Sun, the engineering firm is Spanish. Locals have apparently been wondering if the bridge was built to accommodate Northern Ontario’s temperature swings.
Made it through a whiteout in Beardmore and back across the bridge a couple of hours ago, and celebrated with a nap in the back of the jeep. Learned that the semi that burned was hauling explosives (a client was speaking with one of the fire crews that responded). An hour and a half to go to home. Buddy the World"s Friendliest Cat will never understand what I do to bring home cat food for him.
I’ve heard that theory, but find it insulting to engineers. Of course they would have taken in environmental considerations. It’s ridiculous to think otherwise.
Canada has no experience in constructing cable-stayed bridges, which is what this bridge is. The contractor needed outside help with the design.
I wouldn’t jump to conclusions. But what kind of professional engineer would NOT consider the environment? I don’t believe it. I don’t know what the failure mechanism is, but let’s not jump to conclusions and blame the engineers.
If I’m wrong I’ll accept it, but I don’t buy it at this point.
Except something clearly went wrong.
Yes, engineers are supposed to take local conditions into account.
But engineers are supposed to build bridges that stay functional for more than two months.
One news story suggests that bolts sheared off. Highways officials are having them tested.
The fact that there was a major structural fail right at the time of the first major cold snap of the winter is certainly a possible factor to be investigated.
Hey, I understand. It may be months before we find out what happened. I’m not quite an engineer, but am giving them the benefit of doubt for now.
My discipline is electronics engineering technology. I work with many competent full-fledged engineers and can’t imagine an oversight so egregious.
Hey, I understand. It may be months before we find out what happened. I’m not quite an engineer, but am giving them the benefit of doubt for now.
My discipline is electronics engineering technology. I work with many competent full-fledged engineers and can’t imagine an oversight so egregious.
I’m no engineer, but I once had the unique and pleasant experience of crossing the Brooklyn Bridge on foot, with a civil engineer friend. He pointed out how the Brooklyn Bridge was “overengineered”–in other words, Roebling (the engineer) had taken every precaution to make sure it wouldn’t fail. The anchoring of the piers in bedrock, the main cables, the support cables, and the cross-support cables, as well as the “box,” as my engineer friend called it, in which the traffic travelled–all were far stronger than necessary. My friend estimated that the Brooklyn Bridge was so “overengineered” that it could stand indefinitely, with proper maintenance. We walked from the Brooklyn side to Manhattan, and back again, and he told me about bridges the whole way.
The Golden Gate Bridge in San Francisco was, in his mind, the perfect suspension bridge. It wasn’t overengineered; it was just right for its location. The engineers found the right height and foundation for the piers, so as to accommodate the necessary catenary curve of the cables (I learned a new word that day: catenary); and took into account the earthquakes that had, and might, occur in San Francisco. Cables were spun accordingly, cross-supports were not needed, and though traffic travelled on top of the box, there was still a box to provide stability.
Then we discussed the Tacoma Narrows bridge–one of the most spectacular suspension bridge fails, and one which you still can find on YouTube today. According to my friend, the engineers on that project failed to take into account the winds that occur in that area. Further, there was hardly any box to speak of–it was simply roadway, hung by cables from the main cables–like the Golden Gate, but without the stability that the Golden Gate’s box offered. When the wind picked up, the bridge warped like a ribbon.
Engineers aren’t perfect. They can and have failed to take local conditions into account, as the Tacoma Narrows bridge failure shows. I’m not about to put the Nipigon bridge problem down to engineers from sunny and warm Spain not understanding winter conditions in northern Ontario, but neither am I willing to say that we should jump to the point where the Spanish engineers are blameless. I guess we will have to wait and see what the ultimate reason for the problem is.
You mean like the oversight when they built their first reactor building at Darlington without first figuring out how to install the reactor once the Exocet walls were competed? They had to commission the building of what was then the world’s largest mobile crane to carry in and lower down the reactor in before the roof was completed. Oops.
I don’t know if the bridge’s cables were improperly tensioned, or the expansion bolt was improperly forged or insufficiently robust in design, or some combination of these, but the bottom line is that the bridge failed on the first typically cold and windy winter day, so an egregious oversight was made.
Presently the end of the roadway is being weighted down by many dozens of concrete highway barriers. The side with the weights on it is still not down to the abutment, but since the roadway is twisted, the other lane is more or less down to the abutment sufficient to permit traffic.
I wonder if the twisted roadway will straighten out once the cables are re-tensioned, and if such massive weight at the end of the roadway’s lanes will harm the roadway? I can’t see this temporary fix being any good for the roadway, and I’m hoping it won’t harm it.
Muffin, is the old bridge still in place and serviceable? Maybe that can help take the traffic load off the new bridge until they fix it.
I’m thinking of the twinning of bridges, such as the Burlington Skyway, the Bluewater Bridge, and so on. Is that possible at Nipigon?
The new two lane bridge was built beside the old two lane bridge. The old two lane bridge has mostly been removed. Construction is starting on a second new two lane bridge where the old two lane bridge was. Once completed, there should be twinned bridges of two lanes each.
This is part of a project to have a divided highway of two lanes on each side from Thunder Bay to Nipigon. After the Nipigon bridge, highways 11 and 17 each go their separate ways, so the the single lane highways thereafter can handle the traffic volumes aside from the routine truck crashes.
Although the reason for twinning the new bridges was to protect against full closure in the event of a problem on or with one of the bridges, this was ignored by tearing down the perfectly functional old bridge before seeing if the new bridge could handle all four seasons, seeing as a highway suspension bridge was terra incognita in Ontario. They were too confident that there would be no problems, and instead of playing it safe, they chose to save money by not being patient.
There was some local opposition to a suspension bridge, for although it looks pretty, a some of us were concerned that ice will drop on pedestrians (the reserve is on one side of the river and the town is on the other, so there is frequent pedestrian traffic) and vehicles in the winter. The designers attempted to assure us that it would not be a problem. I took this as an indication that the designers simply did not comprehend what winters are like here, and instead were intent on building what pleased themselves rather than having a very careful look at the climate and weather, and designing something appropriate. Dysfunctional thinking led to a dysfunctional bridge, and dysfunctional thinking led to a premature demolition of the old bridge. We had a perfectly functional two lane bridge. We were supposed to get four lanes to handle increased truck traffic, and have these split over twinned bridges so as to ensure that there would be no interruption of traffic. Now were are down to one lane with truck weight restrictions over a twisted roadbed being pressed down by concrete blocks, with no guarantee against a further failure at the weighted end of the first span, or at an abutment on the second span. For over a hundred million dollars, and when it must not fail due to it being the only roadway connecting eastern and western Canada, there is no excuse for such gross incompetence. Too much hubris and not enough professionalism.
Ninety years ago, Raymond W. Dull wrote “Mathematics for Engineers”, which became a standard text for many generations of civil engineers. A more dull and thorough approach would have resulted in twinned bridges rather than what now can best be described as a fancified foo-foo failure of a kenetic midden mound.
An engineer from Florida was supposed to fly in yesterday. (Seriously.)
I hope someone brings a parka to the airport for him.
The China manufactured expansion bolt shearing resulted in the first span going SPROING!!!
There are two spans to the bridge.
So come up to the lab and see what’s on the slab. I see you shiver with antici… pation, for if the bolts were of the same quality, we can expect a similar failure on the second span of this two-span bridge.
If the problem was a single defective bolt, then why were the bolts not sufficiently tested prior to use?
It seems to me that if the failure of a single bolt can cause catastrophic failure, you should have two bolts in the design. Bridges are no place to get cute with engineering.
I’m starting to wonder if the federal government should assume jurisdiction over this bridge, given how important it is to the national transportation system.
Hoo boy, what a Constitutional mess that’d start.
I’d like to laugh and makes jokes about how I used to try to work with MTO and how amazingly inept they were, but the thing is that back in the day the one thing they DID do right - and believe me, they did nothing else right - was build stuff. Now they can’t do that, which I would assume is somehow attributable to the Liberal government, which seems to screw up literally everything it tries to do. If the government can’t even keep the roads working we may as well just start busting open each other’s heads to feast on the goo inside.
Hoo boy, what a Constitutional mess that’d start.
I’d like to laugh and makes jokes about how I used to try to work with MTO and how amazingly inept they were, but the thing is that back in the day the one thing they DID do right - and believe me, they did nothing else right - was build stuff. Now they can’t do that, which I would assume is somehow attributable to the Liberal government, which seems to screw up literally everything it tries to do. If the government can’t even keep the roads working we may as well just start busting open each other’s heads to feast on the goo inside.
It wouldn’t be a constitutional mess at all. Parliament has the power to pass an act to declare a work to be for the “general advantage of Canada”. Once it does that, the Feds have jurisdiction, not the province. That’s how the Feds have jurisdiction over grain elevators in the west and nuclear reactors
By the way, interesting anecdote, Spoons. I guess if you’re doing the first major bridge of its type, over-engineering is a natural way to go.