The Hyatt Regency Collapse

The Hyatt Regency walkway collapse can be considered as one of the most costly (in terms of human life) in American History. On July 17, 1981, two suspended walkways within the atrium area of the Hyatt Regency Hotel in Kansan City collapsed. In this report the most probable causes of this disaster were investigated. Documents such as drawings, specifications, and test reports were studied to find the causes. As built, three suspended walkways spanned the atrium at second, third and fourth floor levels and connected the other two sections of the building. The second floor walkway was suspended from that of fourth floor walkway which was directly above it and suspended directly from the atrium roof. In the collapse, the second and fourth floor
walkways fell to the atrium floor. The third floor walkway was not involved in the collapse. According to original design documents, a single set of hanger rods would pass through the second floor and fourth floor box beam to support these two elements from atrium roof. However, during construction, shop drawings were prepared by the fabricator using two set of hanger rod rather than single set doubling the load to be transferred by the fourth floor box beam-hanger rod connection. Under the original load the connection would have had the capacity to resist the estimated acting loads during the time of collapse. Unfortunately, lack of effective communication is one of the major issues which lead to this structural failure.