Wednesday, July 31, 2019
Ethical Disaster of the Hyatt Regency Collapse
Eric Sandler Ethical Disaster of the Hyatt Regency Collapse Construction on the 40-story Hyat Regency Crown Center began in 1978, and the hotel opened on July 1, 1980, after construction delays including an incident on October 14, 1979, when 2,700 square feet of the atrium roof collapsed because one of the roof connections on the north end of the atrium failed. The collapse was the second major structural failure in Kansas City in a little more than two years. On June 4, 1979, the roof of the then-empty Kempar Arena in Kansas City had collapsed without loss of life.The architects and engineering firms at the two collapses were different. One of the defining features of the hotel was its lobby, which featured a multistory atrium crossed by suspended concrete walkways on the second, third and fourth levels, with the fourth level walkway directly above the second level walkway. On July 17, 1981, approximately 2,000 people had gathered in the atrium to participate in and watch a dance co ntest. Dozens stood on the walkways. At 7:05 PM, the walkways on the second, third and fourth floor were packed with visitors as they watched over the active lobby, which was also full of people.The fourth floor bridge was suspended directly over the second floor bridge, with the third floor walkway set off to the side several meters away from the other two. Construction difficulties led to a flawed design change that doubled the load on the connection between the fourth floor walkway support beams and the tie rods carrying the weight of both walkways. This new design could barely handle the dead load weight of the structure itself, much less the weight of the spectators standing on it.The connection failed and both walkways crashed one on top of the other and then into the lobby below, killing 114 people and injuring more than 200 others. The rescue operation lasted well into the next morning and was carried out by an army of emergency personnel, including 34 fire trucks, and param edics and doctors from five area hospitals. Dr. Joseph Waeckerle directed the rescue effort setting up a makeshift morgue in the ruined lobby and turning the hotel's taxi ring into a triage center, helping to organize the wounded by highest need for medical care.Those who could walk were instructed to leave the hotel to simplify the rescue effort, the fatally injured were told they were going to die and given morphine. Workmen from a local construction company were also hired by the city fire department, bringing with them cranes, bulldozers, jackhammers and concrete-cutting power saws. The biggest challenge to the rescue operation came when falling debris severed the hotel's water pipes, flooding the lobby and putting trapped survivors at great risk of drowning. As the pipes were connected to water tanks, as opposed to a public source, the flow could not be shut off.Eventually, Kansas City's fire chief realized that the hotel's front doors were trapping the water in the lobby. On h is orders, a bulldozer was sent in to rip out the doors, which allowed the water to pour out of the lobby and thus eliminated the danger to survivors. In all twelve lives were rescued from the rubble. The two walkways were suspended from a set of steel tie rods, with the second floor walkway hanging directly underneath the fourth floor walkway. The walkway platform was supported on 3 cross-beams suspended by steel rods retained by nuts. The cross-beams were box beams made from C-channels welded toe-to-toe.The original design by Jack D. Gillum and Associates called for three pairs of rods running from the second floor all the way to the ceiling. Investigators eventually determined that the new design supported only 60 percent of the minimum load required by Kansas City building codes. Havens Steel Company, the contractor responsible for manufacturing the rods, objected to the original plan of Jack D. Gillum and Associates, since it required the whole of the rod below the fourth floor to be threaded in order to screw on the nuts to hold the fourth floor walkway in place.These threads would probably have been damaged beyond use as the structure for the fourth floor was hoisted into position. Havens therefore proposed an alternate plan in which two separate sets of tie rods would be used. One connecting the fourth floor walkway to the ceiling, and the other connecting the second floor walkway to the fourth floor walkway. This design change would prove fatal. In the original design, the beams of the fourth floor walkway had to support only the weight of the fourth floor walkway itself, with the weight of the second floor walkway supported completely by the rods.In the revised design, however, the fourth floor beams were required to support both the fourth floor walkway and the second floor walkway hanging from it. With the load on the fourth-floor beams doubled, Havens' proposed design could bear only 30 percent of the mandated minimum load (60 percent in the origi nal design). The serious flaws of the revised design were further compounded by the fact that both designs placed the bolts directly in a welded joint between two facing C-channels, the weakest structural point in the box beams.Photographs of the wreckage show excessive deformations of the cross-section. In the failure the box beams split at the weld and the nut supporting them slipped through. Since the construction process includes the work and ideas of many different people, the process can become unclear, especially when meeting deadlines and budget requirements. Such a fast-paced environment stems from the concept that ââ¬Å"time is money. â⬠This concept constantly drives the construction industry to seek quicker methods to transfer ideas from paper to structures of concrete and steel.It has become common practice in the construction industry to begin the actual construction of a building prior to the design work being completed. The Hyatt Regency Hotel was built on this fast-track type of schedule. The main reason for the walkway collapse was not a failure of materials. It was a communication failure. In the case of the Hyatt Regency Hotel, the structural engineer sent a sketch of the proposed walkway connections to the steel fabricator. The structural engineer had assumed that the fabricator understood that he was to design the connections himself.Since the structural drawings did not state that the walkway connections were only a preliminary sketch, the steel fabricator assumed that the sketch was a finalized drawing. The fabricator simply copied the engineerââ¬â¢s preliminary sketch of the walkway connection to serve as the shop drawings. The development of the design was then completed. The materials selected for the fabrication were standard strength, size, and grade of material, rather than what should have been used to compensate for the added stress of the altered design. Such neglections can have grave results.The most glaring mistake in this entire chain of events was that the structural engineer did not review the final design. This is an example of deontological ethics because the engineer failed to perform his job to his full potential. As can be seen from the evidence, the real failure that caused the collapse of the Hyatt Regency walkways was actually a failure of communication in the design phase of the project. As a result of the disaster, the two engineers from G. C. E. International lost their professional engineering licenses in the state of Missouri.These engineers were Jack D. Gillum, the engineer of record, and Daniel M. Duncan, the project engineer. The engineer is ultimately responsible for checking the safety of final designs as depicted in shop drawings. When we take the implicit social contract between engineers and society, the issue of public risk and informed consent, and codes of ethics of professional societies into account, it seems clear that the engineer must assume this responsibility when any change in design involving public safety carries a licensed engineer's seal.Yet, if it is assumed that the engineer in the Hyatt case received the fabricator's telephone call requesting a verbal approval of the design change for simplifying assembly, some possible reasons that would make him approve such change are saving money and time, following his immediate supervisor's orders, looking good professionally by simplifying the design, misunderstanding the consequences of his actions, or any combination of the reasons. These reasons do not, however, fall within acceptable standards of engineering professional conduct.Instead, they pave the way for legitimate charges of negligence, incompetence, misconduct and unprofessional conduct in the practice of engineering. When the engineer's actions are compared to professional responsibilities cited in the engineering codes of ethics, an abrogation of professional responsibilities by the engineer in charge is clearly demonstrated. The Missouri Board of Architects, Professional Engineers, and Land Surveyors convicted the engineers employed by Jack D.Gillum and Associates who had signed off on the final drawings of gross negligence, misconduct and unprofessional conduct in the practice of engineering. They all lost their engineering licenses in the states of Missouri and Texas and their membership to ASCE. While Jack D. Gillum and Associates itself was cleared of criminal negligence, it was stripped of its license to be an engineering firm. At least $140 million was awarded to victims and their families in both judgments and settlements in civil lawsuits.A large amount of this money came from Crown Center Corporation, a wholly owned subsidiary of Hallmark Cards which was the owner of the actual hotel franchise. Life and health insurance companies probably absorbed even larger uncompensated losses in policy payouts. A lot was learned from this disaster. As a result of the fatal miscommunication, the American Soc iety of Civil Engineers has now set the precedent that responsibility lies with the engineer's seal.That is, that whoever places their seal of approval upon a set of plans carries the responsibility for the building and the outcome. It is now also required that all load bearing calculations must be checked by a city appointed engineer and that checks be formal. As an industry, it is important for all responsible parties such as the architects, engineers, fabricators, and whoever else is involved, to understand the challenge learned as a result of this fatality. Design presents the industry with a challenge to anticipate any failed detail and to correct it within the design process.
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