Washington I-5 bridge over Skagit River collapses

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I'm not familiar with that part of the country, but this seems like an important bridge, especially with respect to traffic in and out of Canada. Interestingly, it doesn't appear to have been one of the structurally deficient bridges.. it just kind of sucked?

The bridge is not considered structurally deficient but is listed as being "functionally obsolete" - a category meaning that their design is outdated, such as having narrow shoulders are low clearance underneath, according to a database compiled by the Federal Highway Administration.

The bridge was built in 1955 and has a sufficiency rating of 57.4 out of 100, according to federal records. That is well below the statewide average rating of 80, according to an Associated Press analysis of federal data, but 759 bridges in the state have a lower sufficiency score.

Local coverage here

(Also, for those keeping score, this is sadly not an unprecedented event, although thankfully this one is in a more rural area.)
 
A bridge falling on its own is quite different than a bridge collapsing because of a truck apparently carrying a load that was too large for the maximum clearance. If that is actually what occurred, this has massive lawsuit and even criminal charges written all over it.

Witnesses reported seeing a semitruck with an oversized load crossing the bridge and striking a girder before it collapsed.

"I saw it. I was less than 50 feet away from the truck when it hit it," witness Dale Ogden told KING 5. "I had just passed it in the fast lane southbound and it had an oversized load. It was approximately 12 feet wide and over 14 feet tall. It was in the slow lane when I came by...I was behind the flag car and in front of the truck in the other lane and I saw the whip - normally tells you how high they can clear - start hitting the bridge. I looked in my rearview mirror knowing this was not going to turn out well."

"I saw the truck strike the right corner of the bridge. It almost tipped the truck over but it came back down. It tipped it up to about a 30 degree angle to the left and it came back down on its wheels and almost instantaneously behind that I saw girders falling in my rearview mirror."
 
A bridge falling on its own is quite different than a bridge collapsing because of a truck apparently carrying a load that was too large for the maximum clearance. If that is actually what occurred, this has massive lawsuit and even criminal charges written all over it.

Still though, it's strange that there would be a load too large for an Interstate Highway. I guess trucks weren't that huge in 1955.
 
The bridge has 457mm less clearence than current standards.
But that is beside the point.

This load was above the legal height for unrestricted movement so the haulier should have checked.

Picture of load that hit the bridge.

http://seattletimes.com/ABPub/zoom/html/2021046256.html
 
Still though, it's strange that there would be a load too large for an Interstate Highway. I guess trucks weren't that huge in 1955.


There's been a big increase in the size and weight of allowed trucks over the past 60 years. Technically the weight limit has been stuck at 80,000 pounds (for a single trailer) since I think the 70s or 80s. But you can get oversized load permits. In the meantime a standard truck trailer has gone from 24 feet to 53 feet in length, width from 8 to 8.5 feet. Height of a standard trailer is supposed to be capped at 13' 6", but there are all sorts of non-standard loads on open truck trailers.

It is the responsibility of the truck operator to know of the size and weight restrictions on any road that use. But it's actually pretty common on their part to just assume that they will get away with it, figuring that there's always a fudge factor in the posted sizes. This being only one of many times that turned out to not be true.
 
The company transporting the oversize load will have a big bill.

From Wasington State


http://www.wsdot.wa.gov/NR/rdonlyres/337A7006-8808-4790-85EA-167C8AC39F2E/0/OverheightLoads.pdf

That particular bridge has been getting bad safety/structural ratings for a long while now. In any event, it should have been able to withstand a truck hitting it in what amounted to a traffic accident without falling into the river.

This could be a case where liability is split between the truck company and Washington DOT.
 
Damn, that's close to me and I hadn't even heard about it yet. I-5 is a major freeway; it's the main north-south route through the west coast states. I've taken that bridge quite a few times.
 
That particular bridge has been getting bad safety/structural ratings for a long while now. In any event, it should have been able to withstand a truck hitting it in what amounted to a traffic accident without falling into the river.

This could be a case where liability is split between the truck company and Washington DOT.

I understand that there are other bridges in the state with lower ratings.

From ASCE

“We cannot hope to have an A+ economy, with a C level infrastructure,” said James Chae, P.E., M.ASCE, president of the Seattle Section. “Washingtonians need to realize that our ailing infrastructure hurts our wallets and our livelihoods. In fact, travel delays cost Washington State drivers and businesses more than 32 million hours a year, valued at over $1.1 billion annually.”

....
Bridges were awarded a C-, in part due to the nearly 400 structurally deficient bridges in Washington State. 36 percent of Washington’s bridges are past their design life of 50 years.

http://blogs.asce.org/govrel/2013/0...n=washington-state-report-card-released-today

I don't know what caused this bridge to fail but it appears to have slid off the pier bearings. The bearing shelf on the abutment is very overgrown. Maybe there was a problem with the expansion joint at the abutment which has allowed excess water down onto the abutment bearings to allow the plant growth. The water could have caused the bearings at the abutment to seize. So the span may have been pulling off the pier bearings and when the truck hit it pushed it over the edge.

Obviously more money needs to be spent on maintenance.
 
Too bad spending money to fix bridges and roads is SOCIALISM
Don't you know, taxes to fix roads are unconstitutional!

I don't know what caused this bridge to fail but it appears to have slid off the pier bearings. The bearing shelf on the abutment is very overgrown. Maybe there was a problem with the expansion joint at the abutment which has allowed excess water down onto the abutment bearings to allow the plant growth. The water could have caused the bearings at the abutment to seize. So the span may have been pulling off the pier bearings and when the truck hit it pushed it over the edge.

Obviously more money needs to be spent on maintenance.
The problem is there aren't high enough taxes to pay for it. I saw this interesting article that said that most of the roads were paid for by cities projecting future growth in taxes from new residents, instead of paying for it up front. Now that many areas have stopped growing, those cities can't pay afford all the road maintenance anymore.
 
I know that bridge well enough. I've traveled over it several times in the past couple of years. It'll be interesting to figure out how to get back home after a small day trip into the countryside.
 
That particular bridge has been getting bad safety/structural ratings for a long while now. In any event, it should have been able to withstand a truck hitting it in what amounted to a traffic accident without falling into the river.

This could be a case where liability is split between the truck company and Washington DOT.

A 60 year old bridge isnt designed to withstand hits from these heavy load trucks. Its appears from the security camera footage that the upper steel truse (sp?) was hit repeatedly by the fast moving truck which was accelerating. This was enough to weaken the upper load strength, causing it fold up.

Modern truse bridges are designed to withstand heavy truck impacts.

I guess we will find out in a few months time what really happened.
 
I imagine this will happen more and more in the next couple of decades. The American Society of Civil Engineers is calling for trillions of dollars the United States simply doesn't have, just to maintain the asphalt we've got now. Roads and bridges all across the country are in shambles because our land-use patterns don't pay for the infrastructure they require..


(Yes, trillions. As in 3.6, by the end of the decade.)
 
3.6t is a drop in the bucket for us if we give up the wars of choice, trim back our military spending, get serious about entitlemebt reform and break the madness of fiscal cliff fantasies. It is not like the 3.6t has to be spent all at once...
 
3.6t is a drop in the bucket for us if we give up the wars of choice, trim back our military spending, get serious about entitlemebt reform and break the madness of fiscal cliff fantasies. It is not like the 3.6t has to be spent all at once...
But you guys need to promote liberty, kill terrorists, and teach people the American style of democracy.
 
3.6t is a drop in the bucket for us if we give up the wars of choice, trim back our military spending, get serious about entitlemebt reform and break the madness of fiscal cliff fantasies. It is not like the 3.6t has to be spent all at once...

And abolish the space program.
 
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