Episode Transcript
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Chain of events. Cause and effect. We
analyse what went right and what went
wrong, as we discover that many
outcomes can be predicted, planned for,
and even prevented. I'm John Chidgey and
this is Causality. Causality is entirely
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Hyatt Regency
Kansas City.
Construction of the 40-story high Hyatt
Regency Hotel in Kansas City Missouri
began in May of 1978 and it opened its
doors to the public on the 1st of July
(01:14):
1980 and remained the tallest building
in Missouri until 1986. The hotel was
situated in the Crown Center commercial
complex which was part of an urban
revitalisation of an older part of
Kansas City near Union Station. The hotel
had a revolving restaurant, an exhibit
hall, conference facilities and more than
700 guest rooms.
One of the other widely publicised
(01:36):
features of the new hotel was its
multi-storey atrium which had three
walkways each at a different floor level,
each suspended from the ceiling above.
The atrium has a large open area
approximately 36m (that's 117 feet)
deep 44m (or 145 feet) wide and
15m (or 50 feet) high containing a bar,
(01:57):
a stage, and a large open space that
would sometimes be used as a dance floor.
Each walkway was 47m (that's 121
feet) long and was constructed from steel,
concrete and glass weighing in at
approximately 29 tonnes (or 64,000 pounds)
each.
The hotel itself was split into two
sections (02:15):
a high-rise section and a
function or events block connected by
the atrium.
Walkways connected those two sections on
levels 2, 3 and 4 with level
3 offset from 2 and 4 such that
levels 2 and 4 walkways were
directly above and below each other,
adjacent to the outside wall, with level
3 independently suspended and adjacent
(02:38):
to the others, closer to the center of
the atrium.
The Hyatt Regency Hotel regularly hosted
a Friday night tea dance with live music
and dance competitions.
a tea dance is a European tradition,
though also called "Thé Dansant" or
"Dancing Tea" in French, was a dance held
in the summer or early autumn, late
(02:58):
afternoons before sunset. With that
background, let's talk about the incident
itself. On Friday evening, the 17th of
July, 1981 the Hyatt Regency Hotel atrium
was once again hosting a regular tea
dance with live music that evening
played by the Steve Miller Orchestra. The
dance was scheduled to go for 3
hours in total starting at 5pm and
(03:19):
finishing by 8pm playing a variety of
Jazz swing music.
At 3pm local time the first people
started arriving and within 90 minutes
the first floor of the atrium was now
fully occupied, forcing people to move to
the atrium terrace and walkways before
the official start at 5pm.
By 7pm the crowd was estimated at
between 1,500 and 2,000 people in the
(03:42):
entire atrium area.
At 7:04pm the band returned and began
playing as part of the dance competition.
At approximately 7:05pm the 4th
floor walkway, with an estimated 20
people standing on it, buckled in the
center and began to fall onto the 2nd
floor walkway directly beneath it. As the
(04:02):
falling walkway impacted the 2nd
floor walkway with approximately 40
people on it, the second walkway then
also collapsed, with both walkways
collapsing onto the ground beneath, near
a very crowded area adjacent to the bar.
The number of people on the walkways has
been impossible to determine with any
certainty, as a television crew covering
the event were changing batteries in
(04:23):
their equipment when the collapse
occurred.
Water pipes were severed in the collapse
and electrical cables were dislodged
leaving the lobby in near darkness with
frequent sparks from arcing electrical
equipment intermittently lighting the
atrium. It took 3 minutes for the
Kansas City Fire Department to be
contacted in the confusion, followed by
the Police Department shortly thereafter.
(04:44):
By 7:18pm a total of 7 ambulances
had arrived at the hotel.
By 7:52pm an estimated 100 firefighters
and emergency workers were now actively
involved in rescuing people from the
wreckage. Due to the weight of the
walkways, heavy cranes were brought in to
remove the debris, with the first walkway
removed by 3:15am the following morning.
(05:06):
The last survivor was pulled from the
debris at approximately 4:30am.
114 people were killed,
and 216 were injured.
It remains the deadliest, unintentional
structural collapse in the history of
the United States.
Let's talk about the investigations.
(05:27):
Yes...there were multiple.
The mayor of Kansas City, Richard L.
Berkley, formally requested the National
Bureau of Standards to independently
investigate the most probable cause of
the walkway collapse.
Their
378 page report examines in great detail
the physics behind the failure and makes
for interesting reading. In 1983 a grand
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jury was convened in Kansas City to
investigate if the collapse was as a
result of any illegal actions of those
involved.
In 1984 the state of Missouri convened
an administrative hearing to determine
whether there had been any violation of
state licensing laws by those involved.
In 1985 the ASCE, that's the American
Society of Civil Engineers also held a
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disciplinary hearing.
The relevant findings from all of these
will be discussed in due course, but
before we get to that let's talk a
little bit about the construction of the
hotel.
The hotel was built in the late 1970s
when there was a period of high
inflation, high interest rates, and high
unemployment. The number of available
construction projects at that time was
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limited and hence the contracting
companies at that time priced very
aggressively to win work so that they
could stay in business. As projects
increased in availability, those same
companies then pushed to close out their
projects they had on the books so they
could start on the next project as soon
as they could.
This era of construction also saw the
popularisation of the so-called "Fast
(06:53):
Track" method of design and construction.
Projects delivered by Fast Track are
characterized by construction leading
ahead of the final completed design and
in the context of civil engineering
specifically, structural design precedes
architectural's final design.
There's reliance on conceptual sketches,
preliminary drawings and early component
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orders with red-lining of shop drawings
and multiple re-issues of design
drawings during the construction phase.
Sounds risky?
Well, if you have good quality assurance
it can still work and on large projects
can reduce the time taken to deliver a
project by 25%,
with the trade-off of increased cost
overall in many cases. Sometimes time is
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money too so the sooner it's built, the
sooner it can make income and those
trade-offs are considered to be worth it
in the end. So for this hotel
construction...who are the players
involved? There are a few. Eldridge and
Son Construction Company was the general
contractor on the project.
Eldridge subcontracted the steel work
fabrication to Havens Steel Company as
(07:56):
the fabricator in December, 1978. Gillum
Colico Structural Engineering
Consultants Incorporated (or GCE) was
selected to perform all structural
engineering services for the design and
construction of the hotel in July of
1976.
Jack Gillum was one of the principals
of GCE. GCE subcontracted all structural
(08:16):
engineering services for the project to
Jack D. Gillum & Associates Limited and
designated Jack Gillum as the
professional engineer for the project,
noting that Jack Gillum was also the
president of that firm and hence he was
the Engineer of Record.
Jack Gillum appointed Daniel Duncan from
Jack D. Gillum & Associates as well as the
(08:37):
project manager for daily work execution,
as well as a project engineer and a
senior project designer in late 1976,
along with a full project team.
Patty, Berkebile & Nelson, Herbert Duncan,
and Monroe & Lefebvre
Architects Planners Consortium,
Inc., (or PBNDML for short) served
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as associate architects and during 1977
developed the basic design and some of
the detailed designs for different parts
of the hotel. In June of 1978, Jack D.
Gillum & Associates lost both the Hyatt
Regency Hotel project's, project
engineer and its senior project designer
in very quick succession, leaving only
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the project manager Daniel Duncan with
any history of the design decisions that
have been made to date. During the
construction phase of the hotel, there
was an incident regarding the atrium. On
Sunday the 14th of October, 1979 during
construction, a section of the East
atrium roof on the North side of the
building above the restaurant area fell
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four stories onto the lobby floor.
Fortunately it happened on a Sunday when
no one was working on site and hence
there were no injuries. A spokesman for
the Crown Center Redevelopment
Corporation, the then owner of the hotel
under construction, stated that a:
"...beam fell because of an
installation problem..."
Following the incident it came to light
(10:01):
that the general contractor Eldridge & Son
was fined
$5,920 for 17 violations during the
hotel's construction. Having said that,
none of these issues were related
directly to the collapse, however are
suggestive of a fast-paced construction
process with an inadequate amount of
quality assurance.
(10:22):
There's quite a lengthy analysis of this
specific incident in the show notes by
Gregory Luth (10:25):
"The Chronology of Hyatt
Regency Collapse" if you're interested.
The key point is that the so-called
installation problem was actually more
of a lack of a cohesive design problem
that during installation was worked
around, rather than questioned and fixed
properly.
Had the designers taken that opportunity
to stop the job and review the design
(10:47):
from end to end they would have more
than likely uncovered the walkway design
issues we're about to go through...but
they didn't.
Let's talk about the walkway design.
The walkway is comprised of four spans
in total with each span denoted by its
interconnecting joints and hanging rods
starting at 7 through to 11. Hence the
first span is designated Span 7-8 then
(11:10):
8-9, 9-10 and 10-11. Before you wonder why
the numbering starts at 7...the numbers
line up with the building's column
numbers, hence the walkways hung between
column 7 and 11 of the overall building
space.
Because the walkways on levels 2 and 4
were joined together by hanging rods, the
4th floor walkway was referred to as
upper and the 2nd floor as lower.
(11:33):
Finally the hanging rods were positioned
on either the East or West side of the
walkway. For example the eastern
centre-most rod connection point on the
4th floor was denoted 9UE.
The box girders connecting the walkway
to the hanger rods were made of 200mm
wide (that's 8") of
c-channel, welded together along their
(11:53):
length hence creating the so-called box.
How heavy was it though?
Because during the investigation they
found significant variability in the
thickness of the concrete decking and
topping materials, so they confirmed the
final weights by weighing several
walkway spans as the design drawings did
not align to what was constructed in
that regard.
(12:14):
Analyzing the fallen walkway sections
led to an estimate of the mass of the
walkway to within a worst case error of
+/- 136kg (or 300
lbs).
The addition of gypsum board to meet
fire endurance requirements added
approximately 1,050kg (that's
2,310lbs) to each walkway span. We'll
(12:35):
get to that shortly. The investigators
therefore concluded that the average
final weight of a single walkway span as
built was 8,050kg
(that's
17,750lbs) which
exceeded the as-designed span weight
by about 8%.
Not a good start.
(12:56):
So what went wrong? We know that the
walkways were 8% heavier than
their design but that's only one issue.
It was determined that the most likely
connection point that failed first was
9UE with transferred load to spans U8-9
and U9-10 on the East connections, then
causing 8UE and 10UE to rapidly fail
(13:18):
with the other side of the walkways
joint 9UW failing as well. The method of
failure was that the nut and washer
pulled through the center of the box
beam under high load.
Given the construction method of welding
x2 c-channels together, the
investigators spent significant time
confirming that the quality of the
welding job on those channels was not a
(13:39):
factor in the incident.
In addition, whilst there were people
present on the walkways it was found in
the investigation that the mass of the
people on the walkways was not a
significant contributing factor to the
failure that they saw in the incident.
The two centre-most spans then rotated
downwards pulling span U10-11 off its
(14:00):
bearing seats at the building column
number 11.
As the upper walkway then fell onto the
lower walkway, it followed a similar
failure progression. The investigation
determined that there were two design
changes that contributed to this
incident, as well as a design gap.
We'll talk about each in turn. The first:
Fire-proofing in March, 1978. A routine
(14:23):
design review by the Codes
Administration Office, Kansas City Public
Works Department resulted in a 6 page
handwritten assessment of the fire
endurance of the walkways structural
steel, dated the 10th of March, 1978. A
meeting was held on the 16th of March,
1978 between representatives of the
Codes Administration Office and the
architects PBNDML with 2 pages of
(14:45):
minutes which included an agreement to
clad the walkway structural steel with
gypsum board to address fire resilience
concerns. Specifically x2 layers of
16mm (that's 5/8") thick
gypsum board supported by 0.8mm
metal studs and nailing strips, then
attached to the structural steel by
power driven fasteners. The structural
(15:05):
drawings were reissued on the 30th of
March, 1978 and it is unclear in the
documentation at the time if any changes
were made to the structural details as a
result of gypsum board being added to
each walkway span. The investigation
concluded that the walkway design did
not get adjusted to account for the
additional load from retrofitting gypsum
(15:27):
board as a fire retardant material
during design. That said, they also
concluded that even if the load from the
gypsum board wasn't present, there would
still have been insufficient redundancy
(also called reserve load capacity) in the
hangar rod design to resist the failure
of a single rod.
Hence, if one breaks, they'll all break.
(15:49):
The second design change, also in March
1978, related to the hangar rod
connection.
In March, 1978 drawings for the walkway
hangar showed a single rod continuously
threaded from top to bottom, that was
suspended from the beams on the atrium
ceiling, passing through the fourth floor
walkway and second floor box beams with
(16:10):
securing nuts and washers at each
walkway level. In early January, 1979 the
drawings were now at the fabricators,
Havens Steel Company, and their
engineering manager called the
structural engineers project manager.
Havens engineering manager raised
concerns about the durability of a
continuously threaded rod over that
length during construction. The original
design called for a nut 6.1m up
(16:32):
the hanger rod and didn't use sleeve
nuts. That, coupled with the higher cost
of manufacture, they proposed to change
the design from a single continuous rod
to two rods instead, with threads on each
end. According to Havens testimony the
structural engineer checked the turning
moment and the sheer force presented at
the box beam for the offset condition
(16:54):
while on the phone and Daniel Duncan
accepted that change over the phone. The
structural engineer then asked the
fabricator to submit the change request
through the "normal channels for approval."
The shop drawings were then marked up to
now have two hanger rods with a
102mm (that's a 4") inset at
the fourth floor walkway connection
(17:15):
point, in place of the original single
continuous hanger rod arrangement. To put
it another way,
the ceiling to upper walkway rods were
on the outside and the upper to lower
walkway rods were offset on the inside
of those.
On the 12th of January, 1979 Havens Steel
Company pulled the Hyatt Regency Project
out of their engineering department and
(17:37):
then subcontracted the for-construction
drafting of the partially completed shop
drawings to an external engineering firm.
This was due to Havens winning a large
project and they required their
engineering resources to be focused on
the new job instead.
The outsourced drawings included the box
beam detail but no rod connection was
shown in its detail, which unfortunately
(17:58):
is common practice in the industry.
Different drawings show different
details based on their final intended
use cases.
To understand the overall design of the
connection configuration to the box
beams, a person would need to consider
all of the drawings and specifications
collectively...
not individually. The offset rod design
change was therefore never submitted for
(18:19):
a formal review in its entirety and the
final connection to the box beams was
only implied on the shop drawings.
They assumed that the connection design
was complete and specified elsewhere, so
they simply added the "weld" symbol at
the connection point, before sending the
drawings out for final approval.
Ordinarily if there are any design
changes required to the shop drawings
(18:40):
they would be submitted under a separate
cover sheet along with a request for
engineering validation of the shop
drawings.
This did not occur.
On the 7th of February the outside
detailer made their final consistency
and completeness checks and the drawings
were sent to the structural engineer for
engineering approval.
With various communication delays the
(19:00):
drawings didn't reach the engineer's
desk until Thursday the 16th of February
and the contractor had requested
expedited approval due to the
construction timetable pressures under
the contract. At that time both the
project engineer and designer had long
since departed and the project manager
Daniel Duncan was too short of time to
review the drawings himself so he
delegated their checking to a senior
(19:22):
technician.
The senior technician was trained in
structural engineering and had two
decades of experience but wasn't
licensed as an engineer.
Whilst he queried about the rod
specification (more on that in a moment)
there were no other significant findings
and the drawings were returned approved
for construction on Sunday the 27th of
February. That's right...they were working
the Sunday to get it done.
(19:43):
This modification essentially doubled
the load transferred from the fourth
floor walkway box beam to the holding
nut for the upper hanging rod from 91kN
to 181kN.
Another way to describe this is the nut
holding the weight of the fourth floor
walkway in the original design only had
(20:04):
the weight of its own floor, in that
segment, applied to it with a continuous
rod. Once a second rod was added, instead
of the load from the lower walkway being
transferred up through the rod to the
ceiling,
since it was hanging from the upper
walkway now (not a common rod) the entire
mass of the lower walkway segment was
(20:24):
applied to the upper walkway as well.
Therefore the mass on the holding nut on
the fourth floor walkway was effectively
doubled.
Having said all of that,
with the correct redundancy factors
applied and under the original design,
accounting for the correct weight of the
walkways as they were built, the minimum
load value needed to be 151kN
(20:48):
even with a single rod design, and this
still didn't meet the AISC that's the
American Institute of Steel Construction
specifications requirements. Specifically
the AISC Specification for "Design,
Fabrication and Erection of Structural
Steel for Buildings" as well as the "Code
of Standard Practice for Steel Buildings
(21:08):
and Bridges" as required by the Kansas
City Building Code. Another key problem
was the design of the walkway support
beam's connection to the hanger rod. The
original design sketch for the rod
connection showed a bracket extending
off of the web of the W8 (that's a Wide
flange I-Beam). W8 (that's the vertical
section of the beam where 8 in W8 is the
(21:28):
height of that beam in inches)
and that had an indicative spacing for
the rod connection with the rod sizing
and forces all drawn on the engineer's
sketch. In March, 1978 the project manager
replaced the W8 beam at the hangar
location with a pair of 8"
channels we previously spoke about,
turned toe to toe, and extended these
(21:49):
past the interconnecting W16 beam. This
was done to eliminate concerns about the
eccentricity of the original suggested
bracket connection with the I-Beam. The
revised design was in effect symmetrical
where the original design wasn't.
The revised engineers sketch also showed
the rod size force and rod grade. When
(22:09):
the draftsman transcribed the engineer's
sketch to a for-construction drawing,
they omitted the note specifying the
strength of a 413MPa (or 60kips)
for the hanger rods. In civil engineering
in that era, writing the load detail on
the sketch
indicated to the fabricator that the
connection design still needed to be
(22:31):
completed, and this was normally part of
the fabricator's scope of work. The
engineer had assumed that the fabricator
would complete the design detail for the
connection to the box beam hanger.
It is not clear why the additional
details were not transcribed by the
draftsman, however the fact that they
weren't, led to a mis-assumption by the
(22:52):
fabricator about whether the connection
design was actually complete. They
believed it was,
when it wasn't, and equally the engineer
believed it was being handled by the
fabricator when it wasn't. Placing the
rod through the weak point of the welded
c-channels may have looked the most
pleasant to the eye however the nature
of c-channels is that they taper from
(23:14):
each corner to each tip furthest from
the back of the "C" such that the tips
are the narrowest parts of the channel.
Placing those tip to tip and then
running a weld seam along them to
join them together and then grinding
that weld flat
for assembly, resulted in a very weak
connection. The welders on site
(23:35):
recognised this and attempted to weld
the inner join line inside the box
section, but they could only reach as far
in as the end of their welding rod
allowed them to.
Hardly precision work and pretty much
unconstructable in that way...laws of
physics and all that.
A final note though about the rod design
change that also occurred in March 1978.
(23:58):
The architect requested the rods be
changed from 44.5mm (that's
1-3/4") to 32mm
(or 1-1/4") to "lighten up"
the appearance of the bridges. The
original drawing showing the rod detail
did not specify the material on the
drawing though the other specifications
suggested standard A36 grade rods (that's
(24:21):
36ksi tensile strength) should be used
based on the original design. To achieve
the load-bearing requirements for the
narrower rod, a grade 60 rod (therefore
with a 60ksi tensile strength) would be
required and this was marked up on the
revised engineer's sketch. Just a quick
note...I talk about minimum yield strength...
(24:42):
that's the amount of stress a material
can withstand before it succumbs to a
permanent deformation and doesn't return
back to where it started. In imperial
units it's usually expressed in ksi
which is kilo pounds per square inch of
pressure. Metric units is normally in
MPa or Mega Pascals of pressure. If you
recall, the final drafting for the for-
(25:02):
construction drawing set was outsourced
by the fabricator to another engineering
firm that had a long-standing business
relationship with the fabricator.
During the course of checking the
drawings the technician from the
outsourced back-drafting company
involved asked the project manager about
the strength of the hanger rods. The
technician's own calculations found that
36ksi steel rod would not fully support
(25:23):
the load indicated on the other
available drawings. The project manager
responded from memory that it was a high
strength rod however no mention of the
specific rod grade was provided.
Further than that, no attempt was made to
verify this by looking at a complete set
of drawings and specifications and the
drawings were issued without this
information detailed on the for-
(25:44):
construction drawing set. Some analyses
of this incident call this out as a
cause of the incident but that's not
really true as the rods themselves
didn't actually fail.
Having said that, I have no doubt at all
that had the box beam joints not failed
first with the passage of enough time
and cumulative deformation of the rods
(26:05):
eventually would have led to a collapse
in the future.
When exactly that could have happened
who can say? Technically...not a cause of
this incident but clearly an error that
could have led to a different incident
had the other issues not beaten them to
it first.
Let's talk a little bit about the legal
fallout. In 1984, Missouri's Board of
(26:26):
Architects, Professional Engineers and
Land Surveyors commenced disciplinary
proceedings against Duncan, Gillum and
GCE.
After a 27-day hearing and weeks of
compiling their report the commission
eventually issued its findings which
were 442 pages long and found all three
parties grossly negligent and revoked
their licences.
(26:46):
Judge James B. Deutsch, an administrative law
judge for Missouri's Administrative
Hearing Commission found the structural
engineers guilty of gross negligence,
misconduct and unprofessional conduct.
They claimed that the design flaws had
resulted from a mis-communication between
Jack D. Gillum & Associates and the
Havens Steel Company. Mr Duncan, Mr Gillum
and GCE unsuccessfully appealed their
(27:08):
decision up to the Missouri Court of
Appeals.
The Court of Appeals also rejected the
more substantive attacks on the
sufficiency of the evidence in the
initial proceedings, stating the
following (27:18):
1) "...Mr Duncan was
responsible for designing and approving
the building structure..." of which the
walkways fell within that scope; "...[T]he
walkways offered a potential of great
danger to human life if defectively
designed..."
2)
"...Mr Duncan approved the fabricator's
change, recommending it to the architect,
(27:40):
and approved shop drawings reflecting it
without confirming its acceptability;
(noting that) the change effectively
doubled the box connection load..." and
3) "...Mr Duncan never reviewed the shop
drawings even though such a review is an
'Engineering Function' that even GCE's
in-house policies required that he
(28:00):
do..."
The Court of Appeals upheld the original
conclusion that (28:03):
"...[t]he conduct
of Duncan from initial design through
shop drawing review and through the
subsequent requested connection review...
supports the Commission's finding of
conscious indifference to
[non-delegatable] professional duty."
The Court of Appeal also upheld
the original conclusion that Mr Gillum
had displayed gross negligence because
(28:25):
he failed as the engineer of record:
"...to assure that the Hyatt engineering
designs and drawings were structurally
sound...prior to impressing their upon his
seal..." and failed "...to assure adequate
shop drawing review."
During the trial the detailer, architect,
fabricator, and technician, all testified
(28:46):
that during construction they had
contacted the project engineer regarding
the structural integrity of the walkway
connection detail. They claimed that each
time it was raised the project engineer
assured them that the connection design
was sound and whilst he claimed to have
checked the detail, in reality there was
no evidence found that he had ever
performed any calculations at all. The
(29:07):
legal repercussions for the Hyatt
engineers firmly established the
Engineer of Records responsibilities for
the structural integrity of an entire
building during construction...including
the shop drawings. Hence in the civil
engineering context, the Engineer of
Record should design and detail all
non-standard structural connections. More
broadly all new designs need to be
(29:29):
thoroughly checked and all modifications
to design details require a formal
written approval from the Engineer of
Record.
The day before that decision was handed
down by Judge Deutsch,
the American Society of Civil Engineers
had announced a new policy of holding
structural engineers responsible for all
elements of structural safety in the
(29:50):
buildings they design. Let's talk about
the aftermath. The hotel reopened
3 months after the incident, after
$5M USD of reconstruction.
A single walkway was reinstalled, only
this time supported from beneath by
concrete pillars.
Other than the 3rd floor now being
left without a connecting walkway the
lobby generally retained its original
(30:11):
design.
The hotel was renamed the Hyatt Regency
Crown Center in 1987, but when Starwood
took over the hotel in November of 2011,
it was renamed the Sheraton Kansas City
Hotel at Crown Center.
Mr Gillum and Mr Duncan had their
engineering licences revoked, as did the
company GCE, and the two had their
memberships to the ASCE revoked as well.
(30:34):
GCE survived only by merging with a
Denver engineering firm (30:37):
Ketcham, Konkel,
Nichol, Barrett.
No criminal charges were filed and no
one was prosecuted.
Compensation claims from the courts
awarded victims around $140M USD
paid by the Crown Center
Redevelopment Corporation, the owner of
the hotel, with multiple significant
insurance payouts on top of that.
(30:59):
In 2015, over three decades later, a
memorial was finally built adjacent to
the hotel and was paid for by the
Skywalk Memorial Foundation. It had taken
the foundation a decade to raise the $550,000
USD to pay for the memorial
and associated maintenance endowment. The
names of each of the victims are etched
(31:20):
in the memorial of which the centerpiece
is a six meter or twenty feet high
abstract sculpture of a couple embraced
as they dance.
So what do we learn from all this?
There are three points I'd like to go
over here. Responsibility of the
engineers during design; Complete design
reviews rather than piecemeal; and
personnel churn.
(31:41):
The Engineer of Record is a commonly
used term in North America which has in
the past and particularly prior to this
incident, had varying interpretations as
the ultimate responsibility of that job
role in a construction project.
The Hyatt Regency walkway collapse has
become the legal precedent against which
the role of EoR has ever since been
defined in the USA. The buck stops with
(32:01):
the Engineer of Record. They are
responsible.
In Australia we have legal requirements
under the Professional Engineers Act and
for many engineering disciplines today,
if you aren't a Registered Professional
Engineer in the state you're operating
in and/or a Chartered Professional
Engineer in Australia then you aren't
allowed to sign off on a design drawing.
(32:22):
I've been an RPEQ in Electrical
Engineering for 17 years and also an RPEQ
in ITEE and a Chartered
Professional Engineer in both as well
and I take those responsibilities
extremely seriously. When I stamp and
sign a drawing it means I've checked
every detail of that drawing to the best
of my ability which is in effect what
the Engineer of Record is required to do
(32:43):
as well. When I'm asked to RPEQ a
drawing, there's also additional
requirements. I need to have been
involved with the design from start to
finish...an aspect that was lacking in the
case of this specific incident. I've been
involved in projects where we've spent
significant amounts of money
subcontracting to find the right RPEQ
(33:03):
from other organizations in order to get
the design correctly validated after
that specific engineer had left the
design organization mid-project. We
tracked them down to their new job
and we got them back. Design reviews for
complex systems aren't as simple as
you'd like sometimes, especially when we
fractionalise our designs. I like to call
(33:24):
it "Fractional Engineering."
The idea that reviewing the design or
change as a whole just takes too long or
has too many hurdles when it's
considered in its entirety, so we break
it into fractions of the whole and
review those,
one fraction or one slice at a time...in
isolation. There's often too much detail
to put on a single drawing or in a
(33:45):
single specification which means the
engineer needs to often read, ingest and
comprehend a significant number of
drawings and information in order to
determine if the design in its entirety
is safe and correct.
That takes more time and as they say, "It
takes as long as it takes, if you have to
do it right."
(34:06):
The time pressures and distractions from
other elements of the building's
construction clearly affected the
outcome in this incident. "It's just a
walkway...I have bigger concerns..." I have no
doubt that kind of mindset was a factor.
Finally though...
personnel churn.
It's insidious and it comes from a
belief that people can be plug and play.
(34:29):
"We're all just numbers." I've worked for
companies that push hard on documenting
everything...turning everything into a
process, with evidence provided for every
single step and then when someone leaves
the organization the management layer
hires someone new and think everything
can just pick up from where it was...no
risk, no problem. Thinking is...any new
(34:49):
person can just read all the documents,
comprehend the design and finish the job.
If only it worked that way.
It is simply not possible to write down
every last detail, every conversation,
every side note, every corridor
conversation, site meeting, inspection
note, and even if it was...could the next
person that wasn't present early in the
(35:09):
project then absorb all of that
information and comprehend its
importance and context in any reasonable
amount of time?
Enough to finish the job without an
incident?
It's complete fiction.
We are not plug and play. We are the sum
of our experiences and we are unique. So
few things in engineering are truly copy
(35:30):
and paste widgets and even if they are
the larger the scale, the differences
location and materials makes can vastly
impact the outcome. It's so important to
keep the core team consistent in
projects and if that means paying more,
giving people what they want to get them
to stay, that's not pandering, that's a
long-term vision about what's the best
for the project and the company overall
(35:53):
and that's what it means to be a good
manager. Not trying the sell of plug and
play, "We'll roll on, it'll be fine..." that's
not management.
Building and maintaining a good, stable,
competent team that communicates well
together makes an enormous difference.
Creating time and space to execute
thorough design reviews does too.
Somewhat of an unusual footnote however.
(36:13):
When something traumatic like this
occurs to a person, they can handle it in
a multitude of ways.
We saw the tragedy of the Challenger
Space Shuttle engineers with Bob Ebling
retiring from engineering, unable to
practice, consumed by guilt, although
admittedly he didn't cause the
Challenger explosion but he did fail to
stop the launch, but in this case
something altogether different happened.
(36:35):
Jack Gillium was born on the 21st of
November, 1928 and graduated from the
University of Kansas with a degree in
Architectural Engineering before being
drafted into the army to serve in the
Korean war between 1950 and 1952.
In the early 1960s he found his own
structural engineering company, Jack D.
Gillum & Associates and was known for
(36:55):
many prominent engineering designs
around the world until Hyatt Regency.
Whilst he initially fought the
allegations against him he ultimately
came to a different conclusion about his
involvement, and accepted that he was in
fact, partly to blame for the incident. As
he lost his engineering license he
instead decided to spend the rest of his
working career advising, teaching and
(37:16):
publicly speaking about how he and his
company had got it wrong and how we can
all learn from it. He wrote multiple
papers including the excellent (37:24):
"The
Engineer of Record and Design
Responsibility" paper that's linked in
the show notes.
He passed away on the 4th of July, 2012
aged 83 years old. I've gone a bit back
and forth on how I feel about him but in
the end Jack Gillum could have gone into
seclusion, wracked by guilt, but he chose
(37:44):
to stay out in front and essentially do
exactly what I'm doing here with
Causality. He tried to educate people
about how it can go wrong as it had for
him personally in his case, to try and
prevent future incidents from occurring.
And that, on balance,
I think that was the right call to make,
(38:04):
and I'm glad he chose that in the end
over alternatives.
At the risk of being a touch bit
flippant, the old and mostly untraceable
saying is (38:14):
"When you assume, you make an
ASS out of U and ME."
The "Fast Track" method of construction
employed here led engineers and
fabricators leaning on assumptions out
of a lack of available time with
horrible results. For those engineers
listening to this now, whether you're
reviewing a design, even if you're not
(38:35):
the EoR, or your CPEng or RPEng aren't on
the line, take that review with the same
level of vigor as if they were. Gather
the information you need to be sure if
the design isn't clear and push back...
if you need more time...you NEED MORE TIME!
If you need to speak with the original
designer...find them! Ask them.
(38:56):
Get clarity.
Get it right.
Being an engineer can be a stressful job
but can also be a rewarding one too. I
regularly think back over my 25 year
career to date and I wonder if someday
an error I made in the past, might turn
out with negative consequences - ones that
I didn't foresee at the time in the past.
(39:17):
I try not to dwell on it but that's not
really the point.
I use those thoughts, those fears, to keep
me sharp. A bit of fear isn't a bad thing.
It's a reminder to take what I do, what
many of us do for a living, very, very
seriously.
Had the structural engineers and
fabricators done the same on this
project,
(39:37):
those 114 people might not have died.
Make the time.
Do better.
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(39:58):
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A big thank you to all of our supporters,
a special thank you to our Silver
Producers (40:08):
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Steven Bridle and
our Gold Producer known only as 'R'.
Causality is heavily researched and
links to all materials used for the
creation of this episode are contained
in the show notes. You can find them in
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(41:21):
This was Causality. I'm John Chidgey.
Thanks so much for listening.