I-5 Bridge Collapse

Bridge was built in 1955. Luckily it was all simple spans so that only one span fell.
 
Post edited because I don't want to make this thread political
 
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It is this attitude that is preventing Congress from actually doing something about our crumbling insfrastructure. There are representatives and senators that want to fix our nation but the do-nothing, spend-nothing crew would obstruct as usual.

I don't like to make it political but I couldn't hold back... maybe the still recent I-35 bridge collapse in Minnesota is playing in to my response here.

Yeah, let's keep politics out of this. But the Minneapolis bridge was caused by a design flaw. We'll see what the cause of this failure was.
 
Looks that some of the truss members buckled. Probably not the cause of the collapse, but a byproduct of bolt failure or a gusset plate failure.
 
Yeah, let's keep politics out of this. But the Minneapolis bridge was caused by a design flaw. We'll see what the cause of this failure was.


Yes, a gusset plate was too thin....though was fine until they kept adding load to the bridge over time.
 
Bridge was built in 1955. Luckily it was all simple spans so that only one span fell.

Is this a common design for bridges, or is it dated? Is there any benefit to making a bridge one continuous span when it's possible to have a simple span design?
 
They are saying right now that a semi with an oversized load clipped one of the beams as it entered the bridge headed south. Not sure if it hit on the top or the side, but the state patrol has a truck stopped on the side of the road a few miles down the highway and are taking lots of photos, measuring it, etc.
 
I-5 bridge collapses over Skagit River, no fatalities | KING5.com Seattle
While the cause of the collapse is still unknown, witnesses reported seeing a semitruck with an oversized load crossing the bridge and striking the beams on the north end before the bridge 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."
 
What is it with Washington State and bridges? One blew down. One sank. Now this.
 
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Bridges are a mess. Most all states, counties, and cities have many that are structurally deficient, alot of them are categorized in worse shape than this bridge (well, before it collapsed). We are falling way behind on our infrastructure. And yes I am a biased Engineer.
 
Yup, that's what's going to happen more often since any bills to improve the infrastructure are being blocked. Luckily, it wasn't as big of a bridge as in Minnesota a few years ago. Our country is falling apart as we spend billions "nation building" other countries.
 
If I were Washington, I'd just wait for that monster Cascadian Subduction Zone Earthquake and then rebuild everything.