Tag Archives: building failtures

Catastrophic Building Collapse

When I was a freshman in Architecture school at the University of Idaho, we watched video footage of the November 7, 1940 collapse of the Tacoma Narrows Bridge (also known as “Gallopin Gertie”). If you have never seen this amazing footage before, you can watch it here:

https://www.youtube.com/watch?v=j-zczJXSxnw

Luckily, most of you will never watch (or worse experience) an actual structural building collapse due to extreme wind and/or snow conditions.

The Building Codes (IBC – International Building Code and IRC – International Residential Code) have prescriptive tables for the use of many materials, within given design parameters. Properly installed materials, should provide for safely constructed buildings, within the parameters of the tables.

On January 11, 2014, gusts of wind up to 86 mph (miles per hour) were recorded at Raleigh, North Carolina. The extreme wind conditions were brought about in the aftermath of a “polar vortex” which first froze much of the country, and then (in the Raleigh area) swung with an 80 degree temperature differential to 70 degrees F.

Well, the best laid plans, do not always result is the best outcomes, as can be seen here (this is a MUST watch complete building collapse): https://www.youtube.com/watch?v=FSPB3snYT8M

Now why is it this building came down?

Building CollapseWithout being able to do a physical inspection and forensic analysis, my best guess would be to blame it on fasteners, or lack thereof. I’ve been accused of being overly anal at times, as I watch things like AETN’s History Channel shows about building structural failures. More often than not, the failures are due not to poor design, but to inadequate connections (using improper or not enough fasteners).

In my humble opinion, it will probably be determined by an insurance company investigator, the OSB (oriented strand board) sheathing on the building which fell was not properly attached.

Another possible issue could be Code published Table values for shear walls be higher than the values determined by testing. In 2012 the Structural Building Components Research Institute (SBCRI) and Qualtim, Inc. submitted their findings in a Technical Evaluation Report (TER No. 1201-02), which leads one to believe the Code values are greater than they perhaps should be. To peruse a copy of the report: https://sbcri.info/system/files/drj/ter/node/94/ter120102shearwallsandbwpdesignvaluesfinal.pdf

The one saving grace of tested materials involving lumber is designers are only allowed to use a value which is 40% of the ultimate strength (Pult), based upon the 5th percentile of testing results. In layperson’s terms, if 100 samples are tested, the results of the fifth from the worst test are determined, and the design value is then only 40% of this. The idea is to have a usable number which should be lower than any possible real life situation.

Why am I so interested in building failures?  In doing this over my 35 plus years, I have changed my basic building design time and again to improve it. I shudder when I see other companies finding new “shortcuts” to increase their profits.  I am all about making money, but not at the expense of human and precious animal lives. In over 20 years, our design has not changed appreciably – at least not in a structural sense.  For me, making sure every building we design will stand up for generations to come is how I sleep well at night.

 

Fabric Buildings and Snow

The research for yesterday’s blog really got me searching on the ‘net for more information on fabric covered buildings. Having no real personal experience with them, it was time for me to be educated.

Articles copyrighted by the Associated Press proved to be very informative.

The company who had manufactured the collapsed Dallas Cowboy’s training facility had past issues, court records show. At least three other of their fabric buildings had fallen in heavy weather since 2002.

The other tent like facilities were warehouse-type buildings in Philadelphia and upstate New York and an indoor arena for horse competition in Oregon. All the fabric buildings fell in weather conditions which included heavy snow.

The 2009 collapse of the Cowboys’ facility in winds injured 12 including a 33-year-old scouting assistant, Rich Behm, whose spine was severed in the accident.

Beth Hungiville, executive director of the Lightweight Structures Association, said four of the membrane-style buildings collapsing in seven years is far from normal.

“That is certainly very unusual,” she said. “You would not usually find that many failures in that short a time.”

Hungiville said her organization, an industry group, was aware of the Philadelphia collapse, which occurred just four months before work began on the Cowboys’ facility, but it didn’t know about the others until the few days following the Cowboy’s facility collapse. According to Hungiville, the other accidents likely didn’t attract widespread attention before the failure of the Cowboys’ structure because they didn’t involve injuries.

“When people aren’t hurt or there’s no one inside (the building), these incidents can go under the radar,” she said.

When a Summit structure covering freight for the Philadelphia Regional Port Authority collapsed in February 2003, it spawned a lengthy court battle which ended with a jury awarding the port more than $3.4 million. The fabric building collapsed because of failure of the design to account for snow buildup on the roof, according to a judge’s ruling.

Another lawsuit, centers on the collapse of a building built for storing ice-melting chemicals in Fort Plain, N.Y. The suit, filed by the insurance carrier for the company owning the fabric building, states negligence caused the building to fall when its membrane was ripped during a snowstorm in February 2007.

“Our claim is, ‘This is upstate New York. Every few years, you’re going to get a blizzard. Don’t sell us this product and say it can withstand this sort of thing when it can’t’,” said William Mullin, the attorney for the plaintiff, Hanover Insurance Co.

The Oregon case arose after a rancher had a fabric building built on his property for dressage competition. The 15,840-square-foot building collapsed in January 2002 under the weight of snow which was “substantially” less than the capacity to which the structure was to have been designed to, according to the lawsuit, which has since been settled.

The rancher, James Webb, said, “If my wife had been in there giving instruction or something, it would have been disastrous.”

I’m not trying to pass judgment upon fabric buildings, just reporting what I found. In contrast, properly designed post frame (pole buildings) have a track record of withstanding wind and snow loads far in excess of the loads they were designed for, before recording any failures.

Whether a one car garage or a multi-acre facility, any building is an investment for the building owner, including the responsibility to build a safe structure.  Due diligence is best done to investigate the success or failure of any potential building system…prior to purchase and construction.