I am an engineer (but not a civil engineer) and this sounds like a complete F***K up by the design engineers. As engineers we design things to not fail, we include safety factors in the design to ensure they don't fail. Someone screwed up.

https://bridgemastersinc.com/engineer...

It would appear that for a span of over 300 feet that the center should have had an, at least, temporary support pier in the center until the cable hanging piers were installed. Gravity most likely overcame the 950 tons suspended on just the abatements at the ends.

While the conception of a project is important for it to be created, the actual engineering and constructors are most important. Governments like to have citizens believe that they are the creators of projects because they fund the projects. E. g., the NASA projects are conceived and funded by government (tax payers) but are created and built by nearly all private firms.

My wife is a PE and has worked at Cal Trans basically all of her adult life, with experience in freeway design, bridge construction, hydro structures, water scour inspection, and seismic retrofits.

Honestly, she totally laughed at the concept - private contractors are the "goal" of cheap government, but unfortunately, they will inevitably cut corners in terms of materials, process, or timeline - all of which impact public safety.

As an inspector, she has to watch the private contractors and consulting-engineers like a "hawk" - they tend to skip testing procedures, use lower-grade materials, and routinely make comments about federal interstate minimum standards like "no Abrams tanks will be driving on this".

CalTrans is certainly an expensive and wasteful organization, with something like 15,000 engineers on staff, but they would never hang a bridge over an open in-use roadway, or put it up and open the roadway without all of the support structures in place. For that matter, they wouldn't try the ABC design process.. it's prone to failure. It's cheap, but obviously, this happens.

Some things really are better left to government... roadway construction, bridges, dams, military, etc.

This is either a (major stupid) design flaw, or more likely a manufacturing flaw. The grout used to secure the steel members in tension may not have set or been applied properly.

As I said before, that fact that it had to be tested meant that it was uncertain, and it should not have been "tested" with a slew of people driving/ riding underneath it on the road. Could it not have been tested somewhere else? Or could not people have been warned away?

So, the remaining Roman aqueducts will never fail...!

Jan

Government is pretty much at a loss to adequately insure safety. They just want to stick themselves into the process to gain wages and retirement, but anything else that might happen is just icing on the cake

I would have thought they tested models of the bridge for loads BEFORE building it. But then again, government inspectors are interested only in governmental power and anything else is simply icing on the cake.

They said the same thing (pretty much) about the Titanic.

There of course was some mistake or fault that caused the collapse, too soon to know exactly what caused the failure. There is speculation based on observation and some data but until a thorough examination is done it will be only a guess. When the cause is determined I doubt if any government inspector will stand up and say; "I am the one who missed that." The government demands the right and need for its inspectors to protect the public but they never take credit for their failures to accomplish their tasks. If they are the final approval for any construction why aren't they the first on the firing line for failure?

What I want to know is how the h*** these women passed the PE exam! Has affirmative action reached there, too?

Jbrenner has a thread going as well and I found this on it:

https://heavy.com/news/2018/03/figg-b...

Interesting, but it still seems they knew there were issues before it happened, called them in as "cosmetic", then it fell down, so either design or building method, or materials seems the most probable causes. Maybe the video of it moved into place will tell, but they had 900 tons of bridge on 2 movers, so if one or the other got the least bit out of sequence in the move, it would have been an awful lot of lateral stress, and concrete is not that flexible.

Sorry CG, but if that is the real way construction shakes out, then you have to have a period of months before any new construction is used, in order to prevent just such a event. It should be built and designed such that it cannot fall down. With the huge burden of government permits, inspections rules and regulations, there either should be almost 0 probability, or dump at least half the regs and rules and inspections as non value added.

It was amazing, the brillian idea was to make it next to the road, then move it across the road. Within a week, it falls down, so my amateur guess is something was not structurally calculated correctly. Just a guess, but (I believe) about 10 million down the drain, unless they can prove it was the builders fault?

But where is the fuselage of the airliner that caused it to collapse?
(Sorry, 911 pentagon humor.)

Your federal tax dollars at work. If only the rest of the federal failures were as obvious.

That "instant bridge" crashed down in an instant, killing people just as fast..
Bet the lowest bid to build was snapped up in an instant.
The salivation of tort attorneys must have been instantaneous too. Me dino can imagine all those suits with briefcases flapping bat wings as they circle the sky above that crashed bridge like vultures, all screeching calls that sounds something like, "Pick meee! Pick meee!"

I've maintained my FL PE license, although I don't live there. It makes me feel for anyone who has her/his stamp on any of the docs associated with the bridge. It can't imagine being involved with a failure high-profile enough to make the news.

"the hazards of a failure is really high and then it would start to decrease."
It sounds odd, but this is absolutely true. We calculate mean time before failure (MTBF), but it's deceptive because usually if you plot time and number of failures you get a graph that shows failures are rare when it's brand new, then they spike due to latent issues that shake out before the MTBF, and then farther out you get paradoxically lower probability of failure in any given time period. All this means if the MTBF is three years, you may get more than half of them failing before that time, but some of them lasting ten years.

It rubs me the wrong way when people not involved with a project, esp before the details are known, say if they had been on the project the failure would not have happened.