'Kansas City Hyatt Walkway Collapse\r'

'Kansas city Hyatt base on balls Collapse Introduction The Hyatt Regency Hotel was built in Kansas city, Missouri in 1978. This hotel consisted of a 40-story hotel tower and gathering facilities, which were connected by an open concept atrium. in look the atrium, there were three walkways that connected the hotel to the conference facilities on the second, trio, and tail reports. The atrium was 145 feet long, 117 feet wide and 50 feet high. On July 17, 1981, approximately 2,000 people had gathered in the atrium to come in in and watch a dance contest.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 entrance hall, which was excessively full of people. The fourth floor bridge was suspend directly over the second floor bridge, with the third floor walkway set off to the side several meters away from the other two. reflection issues guide to a subtle but flawed invent change that multiply the stretch along on the familiarity between the fourth floor walkway take hold beams and the tie rods carrying the freight of the second floor walkway.This youthful design could barely handle the dead load heaviness of the structure itself, oftentimes less the weight of the spectators standing on it. The connection failed and both walkways crashed adept on top of the other and then into the lobby below, killing 114 people and injuring more than 200 others. Mainbody FIG-1 FIG-2 Originally, the second and 4th floor walkways were to be suspended from the identical rod (as shown in fig-1) and held in place by ens.The preliminary design sketches contained a note specifying a strength of 413 MPa for the hanger rods which was omitted on the final structural drawings. followers the general notes in the absence of a spec on the drawing, the contractor used hanger rods with only 248 MPa of strength. This schoolmaster design, however, was highly impractical becaus e it called for a nut 6. 1 meters up the hanger rod and did not use branch nuts. The contractor modified this detail to use 2 hanger rods instead of one (as shown in fig-2) and the engineer ratified the design change without checking it.This design change doubled the stress exerted on the nut under the fourth floor beam. Now this nut supported the weight of 2 walkways instead of just one Conclution FIG-3 FIG-4 neither the original nor the as-built design for the hanger rod satisfied the Kansas urban center building code making the connection affliction inevitable. If, however, the building design had contained more redundancy this stroke may not have resulted in the stark(a) collapse of the walkway.Kaminetzky (1991) suggests two much stronger design alternatives for the connectors. The toe-to-toe descents used in the Hyatt Regency provided for weak join which allowed the nut to pull through the channel/ blow beam assembly initiating the collapse. A back-to-back channel desig n using web stiffeners when necessary (fig-3) or the use of bearing crossplates in conjunction with the toe-to-toe channels (fig-4) would have made the connection much stronger making it much more difficult for the nut to pull throughReferences Engineering Ethics †Lessons Learned: Kansas City Hyatt Walkway Collapse http://www. pdhengineer. com/Course%20Web/Law%20and%20Ethics%20Courses/hyatt_walkway_collapse. htm â€Å"Hyatt Regency Walkway Collapse”. School of Engineering, University of Alabama. http://www. eng. uab. edu/cee/faculty/ndelatte/case_studies_project/Hyatt%20Regency/hyatt. htm#Causes Kaminetzky, Dov, Design and Construction Failures: Lessons from Forensic Investigations (1991). McGraw-Hill, New York, N. Y.\r\n'