Hard Rock Hotel Collapse: Why?


On Saturday
morning, Oct. 12, a hotel under construction at the corner of Rampart and Canal
streets in New Orleans, Louisiana underwent a partial collapse, killing three
workers and injuring 30.  The Hard Rock
Hotel, originally planned as a mixed retail/residential project, had reached a
height of 13 stories when something happened to cause a collapse at the top completed
level.  A chain of floor collapses
ensued, leading to a partial collapse of all the floors above about the seventh
level.  The collapse also damaged the two
tower cranes that were being used on the project, leading to concerns that they
might fall and damage some of the surrounding structures in the densely
populated downtown area.  At this writing
(Wednesday, Oct. 16), the body of one worker has yet to be recovered.

Any time a
construction accident occurs, the entire complex process of planning,
management, and actual construction activity gets called into question.  The construction of a large high-rise such as
the Hard Rock Hotel is an exercise in meticulous coordination and integration
of technologies ranging from computer-aided design to the kind of pumps that
can send many tons of concrete all the way up to the roof of a 13-story building.  With so much heavy stuff being supported in
temporary ways, it’s understandable that something could go wrong. 

For example, the
concrete floors that are poured at each level have to set before they are put
into compression by tensioning cables. 
Try to tighten those cables too early, and you’re liable to squash the
still-weak concrete.  But wait too long
by a day or so, and you’ve added costly time to the construction schedule.  A huge number of time-critical matters have
to be coordinated within a small margin of error for things to go smoothly, and
weather, supplier problems, and other external factors can throw a monkey
wrench into the works. 

Still, most
buildings go up without having multiple floors collapse on each other.  Viewed from the front, the structure looks
like a giant finger just scraped all the floors above the seventh and bent them
downward. 

A structural
engineer named Walter Zehner once worked on the project in its early
stages.  When contacted by a reporter from
the Lafayette Daily Advertiser, he said that it was much too early even
to speculate on the cause of the collapse. 
After retreival of the remaining fatality, engineers will have to
stabilize the structure so that it won’t present an ongoing hazard to
surrounding buildings.  Only then will
the investigation begin, and it might take months.

Construction was
in progress at the time of the collapse, and Zehner says that the remaining eyewitnesses
will be asked what exactly was being done at the time.  It’s possible that someone accidentally
knocked over a support column, for example. 
If a heavy just-poured layer of concrete falls twelve or fifteen feet
onto the floor below it, the impact could well cause the next floor to
collapse, leading to just the kind of destruction that took place.  But all such notions are speculation at this
point, and the investigation will reveal a sequence of events that may be
traced backwards to a possible cause.

In the recent past there
have been some indictments of city inspectors for taking bribes.  A lack of proper municipal oversight might
lead to hazardous conditions that could cause such a collapse, but again, this
is speculation. 

The most recent collapse of
a structure under construction that was covered in this blog was the Florida
International University pedestrian bridge collapse in Miami in 2018.  Six people were killed when a concrete-beam
bridge collapsed just after being set in place. 
The investigation of that accident is still ongoing, but late last year
it was revealed that the National Transportation Safety Board (NTSB) had
determined design errors were at least partly to blame. 

Accidents like the Hard Rock
Hotel collapse can happen even if the plans are flawless.  The 1981 collapse of a pedestrian walkway
inside the atrium of the Hyatt Regency Hotel in Kansas City was due not to any
flaws in design, but to a compromise that the builder made in the support structure
during construction.  Investigations may
reveal that while the New Orleans hotel plans were correct, the builders may
have overlooked something.  Or it could
turn out that a single mistake made by one construction worker led to the
tragedy. 

Not much is known about the
extent of training that typical construction workers receive.  Construction is one of the few remaining
fields in which a person without a high-school degree can earn at least in the
range of $13 an hour, which is the average construction-worker wage in Louisiana
according to a statistic cited by the website indeed.com.  This is scarcely anything to write home
about, unless home is Guatemala, in which case it looks good compared to trying
to be a subsistence farmer.  Nevertheless,
it’s attractive enough to draw workers who are willing to face the dangers and
difficulties that construction work involves, up to and including the chance of
dying in a tragic accident.

We will have to wait to find
out what exactly happened in New Orleans to transform a nearly completed
building into a pile of dangerous rubble. 
And when we do, I hope that any lessons learned will be applied to
future construction sites so that tragedies like this happen less and less
frequently. 



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