record lift

By ctacker (****)

Date 11-23-2007 23:41 Edited 11-24-2007 08:03

I just looked at an old employers website, the set the north american record for lifting a fabricated section, also they have a video of a moment connection failing!
some interesting stuff
http://www.schuffsteel.com/index.htm
look at the videos section

edit: hard to believe dave schuff started this business in his backyard in the 70's

By DaveBoyer (*****)

Date 11-24-2007 03:41

Notice the paint failure as the steel elongagates? This is an accepted method in fatigue testing to indicate elongagation in the material before failure.

By pipeliner01 (**)

Date 11-25-2007 18:44

neat video, never seen a test like that before, still amazes me how much deformation weldments will take before failing

By 803056

Date 11-26-2007 00:57

I agree that this is a very interesting video. The brittle paint shows the stress pattern nicely.

That weld was probably tested to the nth degree before testing and had inspectors watching every weld pass deposited.

I wonder how many of the welds that did fail in the Northridge earthquake would have passed both visual and ultrasonic examinations (performed as they should be). Then the flip side; how many of the welds that failed had mortal defects that triggered the failures when subjected to the loading conditions caused by the earthquake.

Best regards - Al

By XPERTFAB (**)

Date 11-26-2007 06:50

A whole bunch of them in both scenarios!! In fact there are a whole bunch more still needing fix'n that nobody has looked at. Guess we'll get them on the next one. Gosh, as I remember it, there is a bunch of rebar splices that are certainly in question also. Mostly on freeway bridges and overpasses. Not too big of a deal. I am however anxiously waiting to see the performance of the steel encapsulation of concrete bridge support columns in a real world test.
To the credit of the engineers of the day, very few lives were lost given the magnitude of what happened.