The Hyatt Regency road collapsed took place at the Hyatt Regency Kansas City hotel in Kansas City, Missouri, on July 17, 1981. Two sidewalks, one directly above the other, collapsed into the tea dance held at the hotel lobby. The fallen trail killed 114 and injured 216. It was the deadliest structural collapse in US history until the collapse of the World Trade Center tower 20 years later.
Video Hyatt Regency walkway collapse
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The 40-storey Hyatt Hyatt Kansas City development began in May 1978. Despite the delays and setbacks, including the incident on October 14, 1979, when 2,700 square feet (250 m 2 ) of the atrium roof collapsed due to a faulty failure one connection at the north end, the hotel was officially opened on 1 July 1980.
One of the hallmarks of the hotel is the lobby, which combines the elevated atrium presented by elevated walkways from the ceilings. This steel, glass and concrete crossing connects the second, third and fourth floors between the north and south wing. The footpath is about 120 feet (37 m) long and weighs about £ 64,000 (29,000 kg). The fourth level line is aligned directly above the second floor path.
Maps Hyatt Regency walkway collapse
Disaster
On the night of July 17, 1981, about 1,600 people gathered in the atrium to participate and watch the tea dance. At 7:05 am local time (00:05 UTC, 18 July) the second level walkway accommodates about 40 people with more in the third level and an additional 16 to 20 on the fourth level witnessing the crowd's activities in the lobby below. The bridge on the fourth floor was postponed directly on the second floor bridge, with the third floor offset a few meters from the other. Construction difficulties resulted in subtle design changes but defects that doubled the load on the connection between the support beams on the fourth floor and the binding rods carrying the loads of both sidewalks. The new design is barely enough to support the weight of the structure itself, let alone the extra weight of the audience. According to an episode of Seconds From Disaster , many survivors reported hearing a popping sound coming from above them just before the collapse. Only moments later, the fourth floor street suddenly dropped a few inches below the audience, before falling completely to the second floor. Both trails then hit the lobby floor below, resulting in 111 deaths at the scene and 219 injuries. Three additional victims died after being transported to the hospital, bringing the number of deaths to 114.
The rescue operation lasted 14 hours and was done by many emergency personnel, including crew of 34 fire trucks and EMS units and doctors from five local hospitals. The trapped survivors are buried under more than 60 tons of steel, concrete, and glass, which can not be reached by Ford forklifts and the most powerful fire fighting jack. Additional volunteers from surrounding areas responded to requests for firefighting assistance, including construction companies and building equipment stores, carrying hydraulic jack, acetylene torch, compressors, jackhammers, concrete saws and generators. The Kansas City natural disaster response team, known as "Operation Bulldozer", was also called to the scene by land transfer equipment, but was quickly dispatched to make room for a crane that would lift the road portions of the trapped victim. Dr. Joseph Waeckerle, former head of the Kansas City emergency medical system, directed the rescue effort to build an emergency mortuary in the ground floor exhibit area, using the entrance and front lawns of the hotel as a triage area and helping to organize the wounded by the greatest need for medical care. Those who could walk were ordered to leave the hotel to simplify the rescue effort; the severely injured are told that they will die and be given morphine. Often, rescuers have to cut up the body to reach the victims among the wreckage. One victim's right leg stuck under I-beam and had to be amputated by a surgeon, a task equipped with a saw.
One of the major challenges of rescue operations is that the hotel's sprinkler system has been cut off by falling debris, flooding the lobby and putting the trapped survivors at a great risk of drowning. Since the pipes are connected to a water tank, not a public source, the flow can not be stopped. Mark Williams, the last person to be saved alive from the rubble, spent more than nine and a half hours under the skywalk with his legs pulled out of his sock. Williams nearly drowned before Kansas City's fire department realized that the front door of the hotel trapped water in the lobby. On his orders, a bulldozer was sent to break through the doors, allowing water to flow out of the lobby and thus eliminating the danger to those trapped. The fire hose was then placed on top of the broken pipe, directing the water outside the hotel. In addition, the lobby is filled with concrete dust, and visibility is bad because emergency workers cut power to prevent fires.
Twenty-nine people were saved from the rubble.
Investigation
Three days after the disaster, Wayne G. Lischka, an architectural engineer hired by Kansas City Star newspaper, found significant changes to the original design of the sidewalk. Event reporting then got the Star and related publications Kansas City Times Pulitzer Prize for local news reporting in 1982. The KJLA radio station will later get the National Associated Press awards for its report on the night of the disaster.
Two sidewalks are hung from a set of 1,25 mm diameter (32 mm) diameter steel rods, with the second floor pavement hanging directly beneath the fourth floor. The fourth floor road platform is supported by three cross-beams hung by a steel rod kept by the nut. The cross beam is a girder box made of C-channel strips that are welded together lengthwise, with a vacuum between them. The original design by Jack D. Gillum and Associates establishes three pairs of stems that run from the second floor to the ceiling. Researchers finally decided that this design only supports 60% of the minimum load required by Kansas City building codes.
Havens Steel Company, the contractor responsible for the manufacture of the rod, objected to the original plan, therefore requiring all the rods under the fourth floor for screw threads to screws on the nuts to hold the fourth floor in place. Indeed, these threads may have been damaged and can not be used because the structure for the fourth floor is lifted into position with the trunk in place. Therefore Havens proposes an alternative plan in which two separate sets of straps and offsets will be used: one connects the fourth floor to the ceiling, and the other connects the second floor with a walkway to the fourth floor.
This design change proved fatal. In the original design, the beams on the fourth floor should support the weight of the road on the fourth floor, with the second floor weight fully supported by the stem. In a revised design, however, the fourth floor beams are required to support both the fourth floor and the street on the second floor hanging above it.
Serious defects of the revised design are exacerbated by the fact that both designs place bolts directly through a welded joint connecting two C-channels, the weakest structural point in the beam box. The photographs of the ruins show excessive deformation of the cross section. During failure, the box beams are split along the weld and the nuts supporting it slip through the resulting gap between two C channels that have been welded together, contributing to reports that the survivors of the upper path fall several inches as the beans are held only by the top side of the box beam, before it also failed, allowing the whole way to fall.
The researchers concluded that the basic problem was the lack of proper communication between Jack D. Gillum and Associates and Havens Steel. In particular, the drawings prepared by Jack D. Gillum and Associates are only early sketches but are interpreted by Havens as the final drawing. Jack D. Gillum and Associates failed to review the initial design thoroughly, and accepted Havens' proposed plan without performing a baseline calculation that would reveal serious intrinsic flaws - in particular, doubling the load on the fourth-floor beams. He then reveals that when Havens calls Jack D. Gillum and Associates to propose a new design, the engineer they talk to only approves the change over the phone, without looking at the sketch or performing the calculations.
Aftermath
The engineers employed by Jack D. Gillum and Associates who have "approved" the final image found guilty of gross negligence, indecent and unprofessional behavior in engineering practice by the Missouri Architects Council, Professional Engineers and Land Surveyors. Although they were released from all crimes initially charged to them, they all lost their technical license in the states of Missouri, Kansas and Texas and their membership with ASCE. Although the company Jack D. Gillum and Associates was dismissed from a criminal negligence, it lost the license to become an engineering company.
At least $ 140 million was given to victims and their families in both courts and settlements in the next civil suit; large sums of this money come from Crown Center Corporation, a wholly owned subsidiary of Hallmark Cards which is the owner of the hotel real estate. As is the practice of many hoteliers, Hyatt operates a hotel for a fee as a management company, and has no building. Life and health insurance companies tend to have absorbed more uncompensated losses in policy payments.
The Hyatt collapse remains a classic model for ethical studies and engineering errors, as well as disaster management. As a recording engineer for the Hyatt project, Jack D. Gillum (1924-2012) occasionally shares his experiences at engineering conferences in the hope of preventing future errors.
After the disaster, the lobby was reconstructed with only one intersection on the second floor. Unlike previous trails, the new bridge is supported by several columns underneath rather than suspended on the ceiling. As a result, the third floor of the hotel now has disconnected sections on the opposite side of the atrium, so you need to go to the second floor to get to the other side.
Some savers experience considerable stress due to their experience, and then rely on each other in informal support groups. Jackhammer operator "Country" Bill Allman committed suicide.
The hotel was renamed the Hyatt Regency Crown Center in 1987, and again the Sheraton Kansas City in Crown Center in 2011. It has been renovated several times since, although the lobby maintains the same layout and design. The hotel owner announced a $ 13 million renovation as part of marking back to the Sheraton brand that was completed in 2012.
Memorial
In 2008, the Skywalk Memorial Foundation announced a fundraising campaign to build parks and fountains to commemorate events in Washington Square Park, about a block from the hotel. Hallmark cards promise $ 25,000 and the city offers $ 200,000. The Korean War Warning was then planned for the park and in May 2009 city officials said they were considering placing a warning at Hill Hospital Park on 22nd Street and Gillham Road, across the street from the Sheraton. On July 17, 2011 (30th anniversary of the collapse), the Skywalk Memorial Foundation launched a design for the memorial to be built at Hill Park Hospital. Hyatt and Hallmark have authorized the establishment of the monument. However Hyatt Hotels later informed the Skywalk Memorial Foundation that it would not contribute to the warning fund as the hotel is no longer managed by the Hyatt and has become a Sheraton hotel. Sheraton and Starwood are deeply aware and respectful of Kansas City's deep connection to this hotel and want to be part of efforts to honor the victims, the people who congratulations, first responders and family members from the 1981 tragedy. "After a 10-year fundraising effort, the Skywalk Memorial Foundation announced plans to break the warning. On June 15, 2015, the Overland Park City Council decided to approve a $ 25,000 grant to help build it. Construction began on July 17, 2015, the 34th anniversary of the tragedy. The completed memorials are presented in a dedication ceremony on November 12, 2015.
On the 36th anniversary of July 17, 2017, almost two years after the devotion and disclosure of the monument in November 2015, there were four known victims on the memorial statue with a misspelled name.
See also
- Disaster engineering
- Kemper Roof Arena Close
- List of structural failures and collapse
References
Further reading
- Petroski, Henry. For Engineers Are Humans: The Role of Failure in Structural Design , New York: Random House, 1985. See especially. pages 85-93 in the chapter "Accidents Waiting To Happen." For example, page 89: "Once the path is up there, there is a report that construction workers find an elevated shortcut above an unstable atrium under a heavy wheelbarrow, but construction traffic is simply diverted and the design still seems to have not been checked or found desirable. "
- Marshall, Richard D.; et al. (May 1982). The investigation of the Kansas City Hyatt Regency sidewalk collapsed . Building Science Series. 143 . US Department of Commerce, National Bureau of Standards . Retrieved 2018-02-17 .
- Levey, M.; Salvadori, M.; Woest, K. (1994). Why Buildings Fall: How Structures Fail . W. W. Norton & amp; Company. ISBN: 978-0-393-31152-5. < span>
- Murphy, Kevin; Rick Alm and Carol Powers. The Last Dance: The Skywalks Disaster and City Changed: In Memory, 30 Years Later . Kansas City Star Books (1st ed.). Kansas City, Mo. ISBNÃ, 978-1-61169-012-5. - (All royalties the author of this book contributed to the project memorial)
External links
- Technical Ethics - including photos of failed road components
- Failure With Physical presentations
- Network news feature from July 23, 1981, including interview
Source of the article : Wikipedia
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