DMN Investigates Blog: Why did the Cowboys practice facility collapse?

[Chocolate Lab]

On this subject, I will say that I had to laugh when they claimed on "Build it Bigger" that the new stadium would be tornado-proof because of the super-slick membrane on the roof panels. Please... That's absolutely absurd on about a thousand levels.

And this company that built the bubble for Jerry is in huge trouble, if only from the family of poor Mr. Behm. Sixty-four mph winds are nothing less than routine in the thunderstorms we have in this part of the country. It's unforgivable that a structure would collapse during a storm which caused no other structural damage anywhere else in the area.

 

[dback]

One hypothesis I have is that the storm transferred a precise amount of momentum in a precise amount of time and caused the bubble structure to vibrate at one of it's fundamental frequencies. All solids have specific frequencies that cause perfect, symmetric vibrations which maximize the transfer of momentum throughout the solid. Notice in the video of the bubble collapse, the light fixtures are all vibrating almost perfectly together before everything fell. The classic example is the oscillating bridge. Usually things like connectors, fasteners, bolts, rivets, etc. are engineered to be rigid enough to withstand and reduce these vibrations in solid structures. It is possible that the short, intense burst of wind excited one of these vibrations and caused something to fail and when one thing failed it led to a chain reaction.

Just my two cents.

 

[Alumni2k11]

I thought the Bengals practiced in a prison yard?

:laugh2:

 

[silverbear]

I thought the Bengals practiced in a prison yard?

That was the plan at first, but if fell through... the inmates at the chosen penal facility circulated a petition, they didn't want to be corrupted by coming into contact with the thugs they call the Bengals players... they pointed out that it would be counterproductive to their rehab to associate with that type of criminal while still incarcerated...

The inmates' next step was to sue the state, saying that being forced to watch the Bengals was cruel and unusual punishment, but they ultimately did not have to use that tactic...

 

[TheHustler]

64 mile an hour winds don't seem excessive enough to bring a steel beam structure down...I have to suspect there was design flaw here or faulty parts. Jerry just needs to build a legit indoor facility. He could have lost multiple key players that would take years to recover if entire team were inside.

Could have lost key players?

Let's get some perspective. People could have died.

 

[SaltwaterServr]

64 mile an hour winds don't seem excessive enough to bring a steel beam structure down...I have to suspect there was design flaw here or faulty parts. Jerry just needs to build a legit indoor facility. He could have lost multiple key players that would take years to recover if entire team were inside.

64 mph were what was measured around the area. A microburst knocked a plane out of the air at the Dallas airport back in the early 90's, late 80's.

We had one hit the apartment complex I lived next too back about 8 years ago. It bent a pair of two inch flag poles at 90 degree angles like they were built that way. Tore off the roofs of several buildings and two buildings over it looked like nothing happened at all. I've been through some ugly weather offshore, and that microburst was nothing like I've ever seen before. Maybe akin to what I watched online when Ike came onshore, but nothing else.

Microburst doesn't register with people like tsunami didn't register with people until a few years ago.

A better way to describe it might be "unformed, highly localized directional downdraft tornado".

It could very well be that the observational towers right outside of the facility could be bent or twisted as well.

 

[joseephuss]

I concur. Here in Southern Maryland, homes are designed to withstand a minimum of 100mph wind speed. I would think anything built in Texas should at least match this criteria.

That is not the case. Most of Maryland is in a coastal region, so higher wind loads are expected. Buildings in the Dallas metroplex area generally would be designed for a minimum fastest wind of 71 mph. This is considered the equivalent of a 3 second gust of 85 mph. This is just the starting point based on building codes. Higher values can be used and then once the design is started you consider the exact location of the building, the neighboring conditions(open land, large bodies of water, other large buildings), the height of the building, the layout of the building, the layout of the roof and the building use among other things.

The fastest recorded winds may have only been 64 mph, but the wind could have been considerably higher at Valley Ranch. As someone already mentioned the area could have been hit by a micro-burst. There may have also been a sudden change in pressure that could have some affect on the building.

 

[Aikbach]

Undoubtedly litigation awaits, the injured people, particularly the paralyzed man is going to be compensated handsomely for his suffering.

 

[notherbob]

I posted this on another thread but it seems more appropriate to post it on this thread:
On the dtox board -( http://www.dtxcowboys.net/community/viewforum.php ) Iceberg posted a still frame from one of the videos as the structure was just starting to come down that showed a straight, unbent beam not attached to anything, falling. That picture showing the undamaged beam falling implies the possibility of bolt failure and the insurance investigation that is sure to follow will be interesting to read when it is done. My guess is that they will find a lot of twisted and broken bolts lying on the ground - just a guess.


Built with aluminum and plastic, huh? Hmmm.

If they build another one, I wonder what changes they'll make?