Question

please read the article in online 'Understanding the Tragic Hyatt Regency Walkway Collapse' and write a summary of the article. should be less than 300 words.

Answer 1

Understanding the Tragic Hyatt Regency Walkway Collapse

On July 17th, 1981, more than 100 people were killed and another 200 or so injured when two walkways collapsed within the Hyatt Regency Kansas City Hotel, the lobby was one of the hotel's defining features and included a multi-story atrium spanned by elevated walkways suspended from the ceiling At around 7 pm, the fourth-floor and second-floor bridges plunged to the atrium's floor.

Support beams and tie rods had been designed to hold the weight of each walkway and any people standing on it.
Walkways were meant to be suspended from the atrium on continuous rods so that load on each floor beam is independently transferred to hanger rods, but this design was changed later which lead to disaster.

The manufacturer of these rods had opinion that the need for the tie rods to be threaded along their entire length meant could easily be damaged during walkway hoisting. They changed the design to include two sets of tie rods to be used instead of the intended continuous one. One set was now to connect the fourth floor to atrium roof. The other for the second-floor walkway attachment to the fourth-floor walkway.

This required the fourth-floor beams to support both the fourth-floor walkway but also the underlying second-floor walkway's dead weight. which lead to increase the load on fourth floor beam.

The tie rods on top sill carry load of both beams as in original design but the two nuts of the 4th floor beam had support load of both walkways, where as they support only 4th floor beam load in original design.

As a result the box beams split along welds and the nuts supporting them slipped through the gap.

This disaster remains a classic model for engineering models, ethics, and errors not to mention disaster management.