Hyatt Regency Walkway Collapse

Isabela Novaes, Kassidy Rehm, Ash Bista, Hamza Sadiq

• Hold paramount the safety, health , and welfare of the public.

• Perform services only in the area of their competence.• Release public statements only in an objective and truthful

manner.• Act for each employer or client as faithful agents or

trustees.• Avoid deceptive acts.• Conduct themselves honorably.

Ethics in Engineering

Building the Hyatt Regency• Construction began in May of 1978 in Kansas City

• The engineers and contractors on the project

• G.C.E. International Inc. - Jack D. Gillum, Daniel M. Dunkin

• Eldridge Construction Company

• Haven Steel Company

• 40 stories tall

• Main focus point of the hotel was the atrium

• featured 3 walkways suspended from the ceiling

• Construction finished in July of 1980

Atrium Ceiling Collapse• Occurred in 1979, a year after

construction began• Hotel owner hired Seiden-Page, an

engineering firm, to investigate• Failure in one of the connections

on the north end

The Walkways• Each approximately 120 feet long and 64,000

lbs in weight• Made of steel, glass and concrete• Connected the north and south wings of the

hotel on floors 2, 3 and 4• Second floor walkway - most easily accessible to

atrium main floor.

• Third floor walkway - led to the hotel ballroom.

• Fourth floor - walkway was least accessible and carried less traffic compared to the other two.

Walkway Design Changes• Hanger rod design was changed• Went from a one-rod system to a

two-rod system• Design was changed to simplify

the assembly task• Doubled the load on the

connector• Each rod was supposed to support

90kN of load, change caused them to each support 180kN of load

Original Design

Changed Design

The Collapse• Due to excessive load, the fourth

floor walkway collapsed and fell onto the second floor walkway

• Both walkways then fell onto the lobby below

• severed the hotel’s sprinkler system and flooded the lobby

• Killed 114 people• Injured over 200 people

Investigation• Wayne G. Lischka, an architectural engineer, was hired by The

Kansas City Star newspaper to investigate the collapse• Discovered the change in design that caused the failure to happen

What Caused Them to Collapse?• Walkways suspended from a set of steel tie rods• Fourth floor walkway platform was supported by 3

cross-beams• box girders - enclosed tubes with multiple walls made from C-

channel strips

• Design only supported 60% of minimum load required by Kansas City building codes

What Caused Them to Collapse? (cont.)

• Haven Steel Company opposed Jack D. Gillum’s original design for the cross-beams

• required the whole rod to be screw threaded in order to hold the fourth floor walkway in place

• Haven Steel thought the threads would be damaged when put in place

• Haven Steel proposed the change from one-rod to two-rods

• This change forced the fourth floor walkway to support the weight of the second floor walkway

What Caused Them to Collapse? (cont.)

• G.C.E.’s design stated that flange beams were to be used along the walkways’ sides and hung from a box beam for better support

• One end of the walkways were designed as a sliding bearing - a roller

• Other end of the walkways were supposed to be welded to a fixed plate - a pin

• The fixed plate end was changed to be a hinge• Change would not have mattered if it was still a single rod system

• after becoming a two-rod system, hanger rods carried more load

• Haven’s change to design, that was then approved by G.C.E., ultimately caused the walkways to collapse

Engineers Aftermath• February 1984, the Missouri board of architects, professional

engineers, and land surveyors filed a complaint against Daniel M. Dunkin, Jack D. Gillum and G.C.E. International Inc.

• Found guilty of:• gross negligence

• misconduct

• unprofessional conduct

• Gillum and Dunkin lost their engineering licenses in the state of Missouri

• G.C.E. lost its certificate of authority as an engineering firm

Change in Codes• American Society of Civil Engineers (ASCE) changed a code to state

that the responsibility of the design lies with the engineer’s seal• the engineer that places the seal of approval upon the set plans carries the

responsibility for the building and its outcome

The Hyatt Regency Today• Now called the Sheraton Kansas City• Renovated numerous time, thought the

lobby still remains the same layout• Lobby reconstructed

• one walkway on the second floor

• supported by several columns underneath, rather than suspended from the ceiling

• Plans for a memorial in Kansas City• July 17th, 2015, exactly 34 years after the

collapse, ground was broken