Quote:
Originally Posted by chachi
Another solid, fact filled, refutation based on evidence and logic. Kudos to you Brodie. Way to bring it strong.  |
would you rather i state "progression" or "progressive" as many times as i possibly can in one reply? i dont know what your background is in structural engineering, but i know you dont know what you are talking about. its ridiculous to compare a building and a bridge in failure modes. i know this because i actually am a structural engineer.
anyways, in non-idiotic news, heres the latest (and most likely):
Cracking, Vibration May Have Contributed to Collapse, Former NTSB Chairman Says
Star Tribune, Minneapolis - Investigators looking into the cause of the Interstate Hwy. 35W bridge collapse are likely to focus on two primary causes -- vibration and fatigue cracking, the former chairman of the National Transportation Safety Board said in an interview early this morning.
Jim Burnett said they should look at whether vibration from the construction work contributed to the collapse, or whether a train that was under the bridge at the time may have been moving, contributing vibration to the bridge.
"Vibration is one of things that cause cracking to propagate," he said. "They will be looking at that."
Burnett, who is in town for a Republican National Committee meeting, was watching the scene at 5 a.m. with other onlookers at the University Avenue SE. northbound entrance.
He also said he was intrigued by a 2001 University of Minnesota study that found signs of "fatigue cracking" in the bridge supports, though he noted that a later report apparently concluded that the bridge was in no immediate danger and did not need major repairs.
"I think that decision is going to come under new scrutiny," he said.
essentially, this was a fatigue crack in a fracture critical member