Over the course of the semester we learned about a couple of building disasters. One of these is the Hyatt – Regency Kansas City skywalk disaster. The collapse occurred in the evening on July 17th 1981. A detailed account of the collapse can be found in this youtube video.
A combination of several factors contributed to the collapse, and if only one mistake had been caught, the risk of disaster would have been substantially minimized. The contribution I will be discussing is the miscommunication that lead to the engineer of record approving a change to the connection without any calculations being conducted. In Missouri, where the building was constructed, calculations for connections were typically done by the fabricator. The shop, however, was in an area where the engineer typically did the calculations before approving the shop drawings. Both sides assumed that the other party had run the numbers and everything was safe.
The part that I don’t understand is how the engineer approved the connection without checking that it is valid. The way I see it is that when an engineer, especially civil and structural, approves a design they take responsibility that it will perform as intended. I would want to know that every calculation is correct. While the engineer might not have the time to run the calculations himself, he could have handed it to another member of the company. Heck, since it is just calculating the allowable load, no design required, an intern could probably do the calculations. The engineer could then just check over the numbers and equations used.
One factor that helped contribute to the collapse was a construction boom in the Kansas City area when the Hyatt was built, meaning that contractors, and engineers alike were busy, meaning there was less time to triple check every aspect. I believe, however, that the 30 minutes it would take to double-check this calculation is worth the 30 minutes that cannot be billed to a different project.