Why Did the FIU Bridge Collapse? - Construction Project Failures & Solutions
Вставка
- Опубліковано 5 вер 2024
- The FIU Bridge Collapse was a catastrophic construction failure at Florida International University in 2018.
The event has been in the news lately as the investigation continues to find out who is responsible for this construction failure of civil engineering.
In this video, former civil engineering and project management expert, Dr. Dean Kashiwagi explains how this event is a supply chain management failure. The reason why the bridge collapsed is because FIU did not properly utilize expertise.
Attend our annual conference: bestvalueconfe...
Connect with Dr. Dean Kashiwagi on LinkedIn: / deankashiwagi
To learn more about the Best Value Approach: pbsrg.com/ or subscribe to our channel!
For professional services in procurement, project management, and contract management visit: www.ksm-inc.com.
Music: Upbeat Acoustic Corporate by Fretbound
Video Link: • Fretbound - Upbeat Ins...
-------
Concepts and processes used are from the Best Value Approach (BVA) developed by Dr. Dean Kashiwagi in 1992 at PBSRG and KSM inc.. It has been tested over 2,000 times delivering $6.6B of services in 10 different countries saving 30% of the project costs. BVA is the most licensed intellectual property (IP) developed at Arizona State University, voted the Most Innovative University in the country for four years in a row. The BVA is a unique procurement and project management philosophy. It is a game-changer in the optimization of services in the age of information systems, robotics, and project management automation. Footage comes from free procurement courses and live presentations on management skills vs leadership skills. The founding philosophy is the Information Measurement Theory.
From what I remember of the NTSB report, the main factors where that there had to be changes made to the slab over the support structure, including a step and holes cut for drain pipes. Cracking was noted, and the solution determined on-site was the tendons needed tightening. Another thing noted was that the design had no redundant load paths in the event of a failure. The design people approved the modifications without any thought.
I can't help but wonder, as they planned to making it a faux cable-stayed bridge, would it have survived had it actually been cable-stayed?
I have seen many cases where a change is made, but doesn't get radiated out to trigger a re-analysis, and they tend to accumulate. The system can tolerate some minor changes, but you cannot gloss over them. At the micro level, the critical qualities aren't recognized, and at the macro level, the changes to the critical quality isn't recognized. Hyatt Regency walkway collapse (support and box girder design), or the Big Dig tunnel ceiling collapse (change from physical interference anchors to epoxy anchors) are examples.
Have to be on your A game when dealing with sexy designs... There are always tradeoffs.
The workers on that job were the first to call out the potential failure of the bridge. No one listened to them. I was on a job where substandard beams were holding up the metal decking under the concrete placement of the floor. To get a flat floor more and more concrete was added. Thankfully there was no collapse of the floor but the next day you could see bent steel I-beams under the area of the concrete placement. After that day, temporary supports were installed and remained until the new concrete came up to the specified strength.
The roughening of a joint just increases the resistance of a cold joint to slipping, but that would not have made the structure safe. The node that broke was grossly underdesigned, according to the NTSB. The shocking thing is that any P.E. should have recognized that the structure was failing and acted to close the road, but the Engineer of Record went around telling everybody that there was no safety concern.
Wow, that is really fascinating! The real danger isn't engineering, it's bureaucracy.
How fast did the bridge get built? How fast did you right the checks to the five people who died?
"Realize they didn't have the expertise..." yes there is a lot of this. It's also called "you don't know what you don't know". It may be a shortcoming in current university curricula that have become watered down over the past 40 years. What they should have realized is that nobody builds concrete trusses so there must be a reason, and nobody can have expertise in building concrete trusses because nobody builds them.
"Rough up the concrete" is not due to using new state of the art concrete, it applies to interfaces between any type of concrete. It has been in the building code since the very first edition of the ACI Building Code for Ultimate Strength Design. It's a matter of developing friction. Smooth concrete won't develop as much friction. It is possible that the original engineer did not anticipate the bridge would be constructed with joints in certain locations, and they didn't know to specify how the interfaces would be prepared. This was the weak point in the design, anyone experienced in tracking load paths through a structure would have seen it.
This is fantastic insight! Thanks for sharing.
Ridiculous not to take those cracks seriously.
I could have had shoring under the bridge...in a day. Cribbing, timber piles, steel postshores...ANYTHING. Just help transfer some load.
Shores could even be on the medians, so not even a traffic hindrance.
They actually had put aesthetics before health and safety.
The concrete had to be roughened because the shear stresses across the pour joint was high enough that it required roughening. It wasn't because there was a special state of the art concrete. Even with the roughening, the joint still did not meet code. It would just be less likely to fail if it was roughened. The structural engineer did not only under designed the joint, he likely knew that the joint was under designed the day of the collapse. The issue was obvious to an experienced trained structural engineer. Before the collapse, the engineer discussed connecting the north joint back to the joint to the south in order to share the shear in the joint. He violated the most important tenant of the practice of engineering and that is not to endanger the public. The life and safety of the public is paramount. Honest mistakes happen and people can get killed or hurt but I would not characterize this as an honest mistake.
Great insights! That is the most important takeaway; the issue is obvious to an expert structural engineer.