[nyalpine90]

few beams or columns in the center would've probably avoided from collapsing.

[Ultimateone]

Originally Posted by nyalpine90

few beams or columns in the center would've probably avoided from collapsing.

That's what really makes no sense looking at it and the length and weight... being an engineer I am just shocked at it all.

[Teufel_Hunden]

What???

http://www.foxnews.com/us/2018/03/16...mpression=true

[nyalpine90]

Originally Posted by Ultimateone

That's what really makes no sense looking at it and the length and weight... being an engineer I am just shocked at it all.

im a plumbing designer/engineer, I can see why bridge collapse right away because there is no support... it sad that people died because of this big mistake. The bridge had no structure to support its weight. There is video of the design phase and there is center structure that was not built!

https://www.yahoo.com/gma/florida-br...opstories.html

[IK6SPEED]

Originally Posted by nyalpine90

few beams or columns in the center would've probably avoided from collapsing.

Originally Posted by Ultimateone

That's what really makes no sense looking at it and the length and weight... being an engineer I am just shocked at it all.

Originally Posted by nyalpine90

im a plumbing designer/engineer, I can see why bridge collapse right away because there is no support... it sad that people died because of this big mistake. The bridge had no structure to support its weight. There is video of the design phase and there is center structure that was not built!

It is very easy to put in a ~100 ft bridge, much less a foot bridge with minimum weight expected on it. The key is distributing the weight, which is done via cables on the top.

The bridge and those cables was going through tweaking (stress testing) and the cable on the crane providing support (to take support off the bridge while this was going on) snapped.

It was a failure of the crane’s cable, not the bridge.

[BuiltnBoostedZ]

Been in construction management for 20 years. The low bidder isn't always the one you want. Reputation, previous job experience (especially bridge construction), and painlessness associated with management is who you want. This was a horrible accident but could have been prevented.

[UncleWede]

Originally Posted by Teufel_Hunden

My fault, I thought I heard people were on the bridge.

Construction workers, some of whom were also injured. Don't recall if any of them died.

[overcoil]

Originally Posted by IK6SPEED

It is very easy to put in a ~100 ft bridge, much less a foot bridge with minimum weight expected on it. The key is distributing the weight, which is done via cables on the top.

The bridge and those cables was going through tweaking (stress testing) and the cable on the crane providing support (to take support off the bridge while this was going on) snapped.

It was a failure of the crane’s cable, not the bridge.

I know nothing about bridges, so I thought I'd ask you.
Other then the crane cable, where are the bridges cables?
I thought this was a simple concrete girder bridge how are the cables attached?

[IK6SPEED]

Originally Posted by ScottSinger

I know nothing about bridges, so I thought I'd ask you.
Other then the crane cable, where are the bridges cables?
I thought this was a simple concrete girder bridge how are the cables attached?

Zoom in on top and you can see points of attachment.

Also note the braces connecting top and bottom to distribute weight at those points.

Remember, students crossing do not need to have a 40+ ton weight load such as a vehicle bridge.

[mkoesel]

Originally Posted by IK6SPEED

How do you read it?

I read it as stated which is that he was not sure a bridge was necessary. He did not mention acceptable loss of life.

If we are motivated enough and pedantic enough, we could impeach any post in any thread in this forum on the basis of implied consequence. For example, we could turn any discussion into an argument about whether all of us, as automotive enthusiasts, think that it is ok to speed despite the higher risk to other motorists associated with that act or to drive vehicles which expel higher levels of tailpipe emissions than is necessary for human transport.

But we are not going to do that because there are rules about diverting discussions off the topic of the thread. But its not just that. We are also not going to do that because we are adults and we are going to work together to make BimmerPost a friendly place. We are not going to exhibit deliberate hostility toward others simply because we may not agree with them on everything.

Since we all understand each other, I know that this particular thread will henceforth be limited to the topic of the bridge collapse and tragedy that killed at least four people. And out of respect for them, we are not going to make it into some political debate.

Thank you all for enjoying BimmerPost in compliance with the rules. Have a great day.

[RickFLM4]

Is it common to stress test a bridge while traffic is flowing underneath it? I don't know the answer and this is nowhere near my field, but conceptually seems odd, without having a background to understand how the process works.

[UncleWede]

^ Additionally, I saw a student on interview complaining that you should work on a bridge AT ALL while traffic is flowing. Were that the case, there is a lot of traffic that is going to be disrupted to allow all the continuing bridge repair that must be done. Can we not have traffic on Golden Gate since they are painting and checking those cables (or any other similar suspension bridge?)

[jgoens]

Originally Posted by UncleWede

^ Additionally, I saw a student on interview complaining that you should work on a bridge AT ALL while traffic is flowing. Were that the case, there is a lot of traffic that is going to be disrupted to allow all the continuing bridge repair that must be done. Can we not have traffic on Golden Gate since they are painting and checking those cables (or any other similar suspension bridge?)

Isn't the Golden Gate a completely different animal?

[UncleWede]

Originally Posted by jgoens

Isn't the Golden Gate a completely different animal?

The interviewed person asked that no work be done on any bridge while there was traffic on/under it.

Be careful what you wish for!

[nyalpine90]

Originally Posted by IK6SPEED

It is very easy to put in a ~100 ft bridge, much less a foot bridge with minimum weight expected on it. The key is distributing the weight, which is done via cables on the top.

The bridge and those cables was going through tweaking (stress testing) and the cable on the crane providing support (to take support off the bridge while this was going on) snapped.

It was a failure of the crane’s cable, not the bridge.

well i guess the results can say that crane, cables werent sufficient to support the massive bridge. the center columns wouldve been great structure to support the weight.

[jgoens]

Originally Posted by UncleWede

The interviewed person asked that no work be done on any bridge while there was traffic on/under it.

Be careful what you wish for!

The GG has maintenance done pretty much every day year round, so they would have to close it. Maybe just build another bridge, because the bay bridge went so well.

[IK6SPEED]

Originally Posted by UncleWede

^ Additionally, I saw a student on interview complaining that you should work on a bridge AT ALL while traffic is flowing. Were that the case, there is a lot of traffic that is going to be disrupted to allow all the continuing bridge repair that must be done. Can we not have traffic on Golden Gate since they are painting and checking those cables (or any other similar suspension bridge?)

Most likely, Golden Gate Bridge (like Hoover Dam) over engineered as most things built during that time were, because of lack of computing power on forces acting against each other (human mind could not explore all the possibilities of stress).

If not, temporary cables would be attached to support weight while another cable is replaced.

This bridge was placed in position, but had not been “installed”.

Again, cable on crane is most likely culprit according to eyewitnesses on site in Cars short of intersection when collapse happened, not bridge failure.

[IK6SPEED]

Originally Posted by nyalpine90

well i guess the results can say that crane, cables werent sufficient to support the massive bridge. the center columns wouldve been great structure to support the weight.

It was obviously determined that would have presented other driver sight issues or driver safety issues. Perhaps not enough room in median.

Then again, an 18 wheeler might have taken that center support out, causing death in cars AND students above.

Regardless, center column wasn’t a big deal in today’s engineering. The bridge was designed to withstand a Cat 5 Hurricane, so it wasn’t some Swinging Amazon Rope Bridge across a river.

[UncleWede]

A single point of failure, on a 100-ton bridge, held with just one crane?

Even Tony Beets wouldn't try that

[onsafari]

Originally Posted by IK6SPEED

It is very easy to put in a ~100 ft bridge, much less a foot bridge with minimum weight expected on it. The key is distributing the weight, which is done via cables on the top.

The bridge and those cables was going through tweaking (stress testing) and the cable on the crane providing support (to take support off the bridge while this was going on) snapped.

It was a failure of the crane’s cable, not the bridge.

I don't believe you are correct with the crane cable snapping as there was no crane on site when the bridge collapsed. If you look at pictures and video right after this happened there is not a crane within site. Not to mention it's not legal by any means to have a crane with it's boom over the road while it's open. This bridge was 100% supported buy itself and should have had a temp support mid span until the mast and cables that were intended to support the bridge were installed.

[IK6SPEED]

Originally Posted by onsafari

I don't believe you are correct with the crane cable snapping as there was no crane on site when the bridge collapsed. If you look at pictures and video right after this happened there is not a crane within site. Not to mention it's not legal by any means to have a crane with it's boom over the road while it's open. This bridge was 100% supported buy itself and should have had a temp support mid span until the mast and cables that were intended to support the bridge were installed.

Incorrect.

Crane was moved out to provide room for rescuers according to eyewitnesses.

Again, examine picture I posted right after collapse.

You will note no first responders or rescue trucks.

Furthermore, normal vehicles there, not fire trucks and you can see 1 car turning around to get out.

[IK6SPEED]

Very different than this.

BTW, notice red crane in upper left they are bringing in.

Why not use crane involved and on site already instead of moving it off scene?

Cable broke, that’s why.