Fuck. I-5 collapsed in WA

[Chugachjed]

It does seem like a weird concept to me. Just looking at them on wikipedia, it's sorta odd that the three longest ones in the world are all in Washington, I wonder why that is.

Weed. The enginerds are high as fuck.

[DJSapp]

Good God, what were they thinking????

Good god willie, calm down. I said it's not ideal, not that it couldn't be done. Steel vs. concrete bridge design is a game of compromises. Steel will last longer, but you have to keep up on the painting and inspection. Steel sections can be repaired with relative ease while keeping the bridge open. Typically steel will cost more on the west coast (opening up more Chinese steel imports is a polyasshat discussion). Concrete can take a hit from a vehicle better than steel. Reinforced concrete does not withstand thermal variance as well as steel. Concrete reinforcement cannot be replaced or repaired without extensive reshoring and is vulnerable to corossive attack from salt air in marine environments (which is why rust is bleeding through every pier in the key west bridge photo on the old bridge). Acid rain (not a west coast issue) is a consideration, as it eats at the cement. The epoxy coated rebar and admixtures I previously mentioned are good defenses, but they aren't time tested yet. They're new technology and in 30-40 more years we may have a huge issue with concrete bridges, or not. We don't know.

Other considerations are the length of span, longer span concrete bridges are typically post tensioned, which makes them even more vulnerable to age and the elements. They are counting on the post tension cables to keep it supported, but if the bridge is compromised enough or in the wrong places it will fall just the same. This post-tensioning is the only modern reason concrete can be a consideration on longer span bridges, without it, the weight to length ratio for concrete blows chunks.

Basically, you weigh out a shitload of issues and try to decide on a design. There is no perfect answer. Sometimes you go with both concrete and steel sections. Hell, 4/5 of the pictures you put up are a concrete/steel composite design :P

[Chainsaw_Willie]

I'm calm. What are you some kind of bridge engineer?!?!

I get what you're saying, just pointing out that lots and lots of bridges used in marine environments use concrete beams and have no overhead superstructure.


I've worked in a lot of buildings with PT cables in the floors. Some dumbass hit one when core drilling one time. The ensuing shitstorm was impressive, and I'm damn glad it wasn't my company that did it.

[DJSapp]

I've worked in a lot of buildings with PT cables in the floors. Some dumbass hit one when core drilling one time. The ensuing shitstorm was impressive, and I'm damn glad it wasn't my company that did it.

That must have been a bad day. Holy shit.

FWIW, the PT cables used in bridges make those floor cables look like little girlie jumpropes.

[PNWbrit]

it's sorta odd that the three longest ones in the world are all in Washington, I wonder why that is.

Not many places need 12 plus lanes of traffic over two freeways a mile or so apart across a mile wide, 200 feet deep lake .

Anything else would have required something of the scale & $$$s of at least two SF-Oakland Bay bridges?

Both of which would also have been a hideous eyesore, whereas the floating bridges minimally impact the skyline.

[mobygrape]

It'll get hit again.


(you're better off just muting it)

http://11foot8.com

So awesome, so funny.

[AK47bp]

Not many places need 12 plus lanes of traffic over two freeways a mile or so apart across a mile wide, 200 feet deep lake .

Anything else would have required something of the scale & $$$s of at least two SF-Oakland Bay bridges?

Both of which would also have been a hideous eyesore, whereas the floating bridges minimally impact the skyline.

I remember talking to a disaster preparedness guy during a business continuity planning session. He said if a major earthquake were to severely damage the Ballard Locks, Lake Washington water level would drop enough to cripple the floating bridges.

Not sure if this is true but I think the lake is kept at a higher level than the sound to prevent seawater from running into the lake.

My goggling didn't return any info on the subject.

Anyone heard of this theory?

[PNWbrit]

I remember talking to a disaster preparedness guy during a business continuity planning session. He said if a major earthquake were to severely damage the Ballard Locks, Lake Washington water level would drop enough to cripple the floating bridges.

Not sure if this is true but I think the lake is kept at a higher level than the sound to prevent seawater from running into the lake.

My goggling didn't return any info on the subject.

Anyone heard of this theory?

I know that there's a sump dug into the canal bed east of the locks where sea water from lock openings sinks and then is drained back to the sound side.

I'd have guessed a quake big enough to damage the locks would be plenty big enough to fuck up the bridges first anyway?

[AK47bp]

Ah, I guess you have a good point there. If the locks get fucked the bridges are destroyed anyway.

I wonder if a strong enough tsunami could destroy the locks?

[Chainsaw_Willie]

Lake Washington is somewhere on the order of 10-15' higher than sea level IIRC. If the lake were to drain down that much, that could definitely cause problems with the bridges.

[GeezerSteve]

The elevation of Lake Washington is 16 to 20+ feet, depending on the tide level of Puget Sound. Before construction of the Montlake Cut -- back when the lake flowed out the Black River to the Duwamish -- the lake level was 9 feet higher, i.e., around 25' to 30' above sea level. Reclaimed land includes some of Madison Park and Husky Stadium.

[iceman]

you (some American dude is the big boss of CP Rail) did your best to get us back, the bridge just barely avoided collapse.

Since the Calgary bridge didn't actually fall in we'll call it Cda 1 vs US 0.3

Like most Americans, I hadn't heard about that one: http://www.theglobeandmail.com/news/...ticle12881818/

[RootSkier]

I've worked in a lot of buildings with PT cables in the floors. Some dumbass hit one when core drilling one time.

Tell us more.

[jfost]

...Reclaimed land includes some of Madison Park ...

jeezus that's terrible, where did the gays go to sunbathe back then!?!

[GoldMember]

I've worked in a lot of buildings with PT cables in the floors. Some dumbass hit one when core drilling one time. The ensuing shitstorm was impressive, and I'm damn glad it wasn't my company that did it.

Speaking of failed post-tension concrete problems, here's a goody in Belltown:

http://www.treehugger.com/sustainabl...years-old.html

[DJSapp]

Speaking of failed post-tension concrete problems, here's a goody in Belltown:

http://www.treehugger.com/sustainabl...years-old.html

That article is filled to the brim with hyperbole. Then again, with a website called treehugger.com, I wouldn't exactly expect it to be fair or balanced reporting. It's more like an owner using the media to hammer home a warranty issue. You don't knock down a house because of a little bit of dry rot in an overhang.

[Chainsaw_Willie]

Tell us more.

Really not much more to tell. The floor didn't collapse or anything but did crack pretty badly, just lots of political fallout, contractor kicked off the job, endless safety meetings, etc. etc.

I wasn't working near it when it happened but word was it made a helluva bang.

[GoldMember]

That article is filled to the brim with hyperbole. Then again, with a website called treehugger.com, I wouldn't exactly expect it to be fair or balanced reporting. It's more like an owner using the media to hammer home a warranty issue. You don't knock down a house because of a little bit of dry rot in an overhang.

Okay, here, PI article from 2010:

"DPD (Department of Planning and Development) intends to declare the McGuire Apartments unsafe. While the building isn't currently unstable, some cables could begin failing next year, with one-third of them failing by 2019, according to an engineering report prepared for the owners. Tenants in the 272-unit building, which is encased in scaffolding, were instructed to move out as soon as possible. The building needs to be cleared by Dec. 31."

http://www.seattlepi.com/local/artic...ire-897221.php

I only used the other article because of the graphics showing how P-T works and it was the first one to show up when I Googled. Comparing failing post-tension slabs throughout a structure to a little bit of dry rot in an overhang grossly understates what was happening in that building. I saw it a couple of years ago and it was completely enveloped in tarps and scaffolding, due to failed PT ends and grout popping out and dropping to the sidewalk below. I think it's been demolished at this point.

Here's another article regarding the fight over what the final determination for the building was to be, complete with the same graphic as provided in the first article:

http://seattletimes.com/html/localne...mcguire15.html

[DJSapp]

Still not buying it. From your article:

In an earlier e-mail, McCarthy spokeswoman Susan Garritano said her company hopes "the city will recognize that The McGuire is safe and [that] with reasonable repairs and maintenance, at a fraction of the cost of demolition, it will be serviceable to tenants and commercial tenants for its complete useful life."

Carpenter's Tower, a venture of several pension funds and Carpenters Local 131, sued McCarthy in 2007 over construction problems at the 272-unit apartment tower.

While that lawsuit awaits a September trial, the owner announced over the weekend that it would vacate the building by Dec. 31, then demolish it, because the construction problems are too expensive to fix.

Garritano labeled that plan "unreasonable."

Reading between the lines, I got the following out of it: the builder, McCarthy, is more than capable of repairing the building for a price. The owner, who is most likely totally upside down on the building and is bleeding out money, wants to tear it down and sue for defects. The owner (including the local carpenters union) couldn't afford the repairs as housing died along with construction work. Where it gets murky is who was responsible for inspection and where (or if) it went wrong.

It seems to me a case of pulling the plug on a bad investment. They settled behind closed doors, and the building was demoed. If the builder was solely responsible, I absolutely believe they would be repairing it. $60 million buys a lot of repairs. Buildings can be reshored, PT ducts re-drilled and cables replaced, or just retrofit the structure so it no longer relies on the PT. It's a massive pain, but it can be done. McCarthy may have been culpable to a degree, but I really read this as the owner wanting out.

http://www.builderscounsel.com/2010/...ction-dispute/
http://www.seattlepi.com/local/artic...re-1064124.php

[GeezerSteve]

Read between the lines if that's what you like to do. The word around town is that a repair is impracticable, and that demoing is gonna happen.

[GoldMember]

Read between the lines if that's what you like to do. The word around town is that a repair is impracticable, and that demoing is gonna happen.

Demo actually did already happen. It went down in 2011.

Edit: At least I thought it went down in 2011. I know someone was killed in Sep 2011 during demolition of at least part of the structure (separate parking structure?) but I can't seem to find anything that confirms the 25 story tower is gone.