Maybe we should ask the architect.
Posted on 03/16/2018 12:25:26 PM PDT by C19fan
Maybe we should ask the architect.
Not sure it would have been possible to attach cables to only the part which was hoisted over the traffic lanes, without the other half cabled to the central tower simultaneously.
But then, why didn’t they erect the other half first?
What steel? Looking closely at the fallen span, it doesn't appear that there is anything metal in or attached to the concrete ...
It seems obvious to me that the dead load of the bridge would dwarf the typical live load it is designed to carry.
Alberta’s Child, P.E.
I am not a P.E., but do have an M.S. in Mining Engineering.
The type of construction and why it failed have been explained in previous threads. There’s nothing truly unique about the design. Something happened when the concrete bridge was in place and the interior tensioning cables were being adjusted possibly to prepare the bridge for further loading. Concrete takes about a month to cure to spec. My guess is that as the concrete continued to cure and develop more strength the tension on the cable was increased. It looks like they were preparing for addition of the remaining structure when something happened.
Was this architect-designed without an engineer? Lawsuits to follow.
Hurricanes, supposedly, is why the additional support.
The engineering of those bridges were done by some great people, and if ‘a design isn’t broken, do not try to fix it.”
This was deliberately a “one of a kind” design.
Lots more money in that kind of a design. 11 million plus for this bridge. How much went to local politicians?
From “The Book of Obama”....”imagine it, and it will be true forever”. What a genius!
Hard to figure out.
I wondered if the pillar closest to the canal settled, but I haven’t seen the collapse video. That pillar looks like it would have been part of the central pillar later. (If it had lasted the long :-(
I would estimate that it is about a 60/40 or 70/30 split, with longer cantilever span barely supported on the one end. There was an epic failure to allow for any temporary support needed to complete the bridge.
Can you find “what is missing”?
“Design flaw. Blame the coolies and the peons.”
The blame is on dozens of people at least. There are so many people involved in the design, planning, construction, inspection and testing... I can’t believe this wasn’t prevented. How many people raised their hand at one of the meetings and said “hey, maybe we should have some sort of temporary support until the permanent support is in place.” It HAD to at least be a subject of debate. Especially considering it’s a CONCRETE bridge. I am completely dumbfounded and sickened. So preventable.
Yes, it is obvious. I thought of that and posted on it yesterday.
Although a PE, I’m not that kind of an engineer (electrical/electronic, actually). But, I can think.
Also, if you look at the bridge section, all you see is shattered concrete and the occasional reinforcing or tensioning rods. There is no substantial steel in the base section, which is what was supported at the ends and what broke.
In contrast, the superstructure and roof assembly is massively trussed, as it should be if it was planned to be bearing the load through tensioned cable stays. But, if the cable stays aren’t in place, it’s just so much more dead weight!
I wonder who was in charge of the assembly. Blaming the workers, undocumented or legal, is besides the point. Who gave the order to pin the bridge up by its ends without the central tower even being built, let alone attached by the staying cables? There has to be an assembly plan for this tinker toy!
This is the “garbage in, garbage out” mentality that exists due to ignoring the facts. Congratulations, Progressives. You too deserve a trophy.
In most cases the design engineer or architect do not give the constructor instructions on how to build the project. The contractor is expected to hire his own team to manage the construction process. They schedule each step and how it should go together. Then the engineer might have been asked to review their work plan.
my uncle was a steel erector, did a number of pro football stadiums and basketball arenas, he said it is easy to be structurally sound when in place, the engineering is to keep it sound all along the way.
“somethings” have reasons and meanings. That is what I want to know.
Affirmative action rules don’t apply when you are required to take a year each of calculus, physics, chemistry, then throw in thermodynamics, statics, dynamics, strength of materials, concrete design, structures and on and on..
Academic rigor is a manifestation of toxic masculinity!
Disclaimer: Opinions posted on Free Republic are those of the individual posters and do not necessarily represent the opinion of Free Republic or its management. All materials posted herein are protected by copyright law and the exemption for fair use of copyrighted works.