Pedestrian brideg collapse -- kills 6

[Orange Spyder Man]

https://www.msn.com/en-us/news/us/at...4R7&ocid=edgsp

maybe its time to outlaw bridges ..

[SPECTACUALR SPIDERMAN]

Enough with the outlawing of everything, watch demolition man.

[Bob Denman]

Prayers for all of the affected families...

[ARtraveler]

Yup!

[Chupaca]

Saw the surveillance video and it just let go 's to all those affected and especially to the family and friends of the ones that did not suvive...

[IdahoMtnSpyder]

As an engineer it sure looks to me like a stupid design guaranteed to fail. I'm going to speculate that someone, either a young inexperienced engineer, or an old one whose mind is losing it's acuity, input some wrong numbers into a design program and didn't have enough common sense to see that the output was bad. Nor did anyone else in the firm who reviewed the design. I read that some cables were loose and were being tightened when it collapsed. I would not be the least bit surprised if the 'loose' cables had already broken inside the concrete due to being seriously undersized and over stressed. There's a reason why bridge beams have a 'T' shape or a box shape. From the photos it looks like this one did not.

I fear we may have reached the point where experience derived by grunt mathematical work is being replaced by total reliance on, "But that's what the computer said!" I hope this is the wake up call STEM educators need to realize that students have to understand what all those formulas in the computer programs are really doing. This incident is truly sad, but the cost of the wake up call this way is a whole lot lower than if an airliner were to crash due to a computer programming screw up. The formulas that are used to calculate stresses and forces in a bridge have been in computer code for decades now. I wonder how many of those formulas have been carried forward into the programs used today with no one having any idea how they were derived in the first place, nor what the long hand form of the equations are that are the basis of the calculations.

This incident scares me.

[vided]

IMG_2865.jpg

[BajaRon]

As an engineer it sure looks to me like a stupid design guaranteed to fail. I'm going to speculate that someone, either a young inexperienced engineer, or an old one whose mind is losing it's acuity, input some wrong numbers into a design program and didn't have enough common sense to see that the output was bad. Nor did anyone else in the firm who reviewed the design. I read that some cables were loose and were being tightened when it collapsed. I would not be the least bit surprised if the 'loose' cables had already broken inside the concrete due to being seriously undersized and over stressed. There's a reason why bridge beams have a 'T' shape or a box shape. From the photos it looks like this one did not.

I fear we may have reached the point where experience derived by grunt mathematical work is being replaced by total reliance on, "But that's what the computer said!" I hope this is the wake up call STEM educators need to realize that students have to understand what all those formulas in the computer programs are really doing. This incident is truly sad, but the cost of the wake up call this way is a whole lot lower than if an airliner were to crash due to a computer programming screw up. The formulas that are used to calculate stresses and forces in a bridge have been in computer code for decades now. I wonder how many of those formulas have been carried forward into the programs used today with no one having any idea how they were derived in the first place, nor what the long hand form of the equations are that are the basis of the calculations.

This incident scares me.

Sounds like a high probability analysis to me. Especially the cables being loose because they were already broken. You would think that would be obvious to the workers tightening them as they would run out of adjustment with no appreciable change in tension.

This has to be the end result of a good number of failures along the way. This happens all the time in 3rd world countries. And according to many reports. Our current education system is about on par with many 3rd world counties.

[blacklightning]

I got calls from 2 of my riding buddies that know that I am in the precast concrete design business. My first comment was that I haven't done work in Florida in over 15 years. Most of the precast that I do is simply mild steel, and no stressing is involved. I have done precast on a few bridges, but it was all architectural cladding on a steel structure. So sad that this happened. You can bet that there will be a shotgun lawsuit that will hit everyone involved. As for the bridge builder and engineering firm, they can start sending out resumes because that engineering firm will be going under. Even with the required insurance, it will be hard to keep afloat. I heard that they are the ones that did the Viaducts on the BRP. They are shut down right now for repairs and repaving and will not be openned again until Memorial day.

IMG_20170918_165647325_HDR.jpg

Here is a bridge that I did at Liberty University in Virgina. This is only precast cladding on a steel and P.I.P. structure.

IMG_1135.jpg