Hyatt Regency disaster - 1981, Kansas City
Hyatt Regency disaster - 1981, Kansas City
(OP)
Example of PAY ATTENTION to basic statics - just wanted to bring this to attention of younger engineers.
http://en.wikipedia.org/wiki/Hyatt_Regency_walkway...
I believe the engineer who first specified the original detail (which did seem to be safe) neglected to realize that it was impossible to fabricate an all-thread rod of that length, and expect someone to spend who knows how much time threading the nuts up to where they are shown to clamp the boxed C-sections.
When the detail was revised to the more constructible version version shown to the right, the force on the boxed C-sections was multiplied, and the failure mode was by bending the C-flanges and punching thru.
Basic statics. I mean really basic.
http://en.wikipedia.org/wiki/Hyatt_Regency_walkway...
I believe the engineer who first specified the original detail (which did seem to be safe) neglected to realize that it was impossible to fabricate an all-thread rod of that length, and expect someone to spend who knows how much time threading the nuts up to where they are shown to clamp the boxed C-sections.
When the detail was revised to the more constructible version version shown to the right, the force on the boxed C-sections was multiplied, and the failure mode was by bending the C-flanges and punching thru.
Basic statics. I mean really basic.
The definition of a structural engineer: overdesign by a factor of 1.999, instead of the usual 2.






RE: Hyatt Regency disaster - 1981, Kansas City
Michael.
"Science adjusts its views based on what's observed. Faith is the denial of observation so that belief can be preserved." ~ Tim Minchin
RE: Hyatt Regency disaster - 1981, Kansas City
RE: Hyatt Regency disaster - 1981, Kansas City
The way it was explained to us was that the steel fabricator had a junior guy do a crappy design without it being properly checked, assuming that the EOR would check it thoroughly. The EOR assumed the fabricator was the expert in connection design and didn't run any calcs on it. Then when it failed the legal question was who was responsible for the design of the connections?
The legal principle: Risk should be assigned to whomever is best able to manage it.
The Canadian Construction Documents Committee has clarified this in their stipulated price contract (CCDC 2). The steel erector is the person with the expertise in connection design, they are the person responsible for the structural design of the connections, even though the consultant reviews the drawings.
"3.10.6 The Consultant's review is for conformity to the design concept and for general arrangement only."
"3.10.10: "The Consultant's review shall not relieve the Contractor of responsibility for errors or omissions in the Shop Drawings or for meeting all requirements of the Contract Documents"
RE: Hyatt Regency disaster - 1981, Kansas City
Dik
RE: Hyatt Regency disaster - 1981, Kansas City
The definition of a structural engineer: overdesign by a factor of 1.999, instead of the usual 2.
RE: Hyatt Regency disaster - 1981, Kansas City
“Faith is taking the first step even when you don’t see the whole staircase.” MLK
RE: Hyatt Regency disaster - 1981, Kansas City
The definition of a structural engineer: overdesign by a factor of 1.999, instead of the usual 2.
RE: Hyatt Regency disaster - 1981, Kansas City
The states backed down in the face of some fierce lobbying.
Michael.
"Science adjusts its views based on what's observed. Faith is the denial of observation so that belief can be preserved." ~ Tim Minchin
RE: Hyatt Regency disaster - 1981, Kansas City
It is not EOR will full authority on the project all the way through, but it is close. Most authorities (cities, counties, etc) will require a final letter from the engineer. Makes a very big difference and helps both get the job done competently, and the engineer paid.