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| -Short Attention Span Theater- | |
| Lessons of the San Fran Bridge Collapse | |
| 2007-05-01 | |
| Reprinted below is one for the conspiricy loons. In one line of inquiry that could improve future responses, some scientists were studying linkages between the freeway collapse and how the World Trade Center came down on Sept. 11, 2001. The structural failures appear similar, said David McCallen, division leader in nonproliferation, homeland and international security at the Lawrence Livermore National Laboratory. So he's in on the conspiracy, too! The steel supporting the overpass turned pliable after the gasoline-fed fire below reached temperatures up to 2,000 degrees - more than four times as hot as the hottest conventional home oven. Pliable. The engineering term is plastic. Not melted. Whaddaya say, Rosie?
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| Posted by:Bobby |
| #12 Fire heats the steel, whether it be in the bolts, supports, or the beams holding up the concrete roadway. The yield point of steel gets less and less until it becomes hot enough to stretch under load stress, like taffy, then the whole thing comes down. Gasoline does that to things, ya know, when it burns and makes heat. That's it. That's why steel beams are fireproofed in high rises. Bad things happen when 20 stories above start listing when the structural steel columns start to buckle under heat. Jeeze louise. |
| Posted by: Alaska Paul 2007-05-01 22:28 |
| #11 Chuck: It's been 26 years since My materials class, but I thought you could only get martinsite from austenite, which has a higher temperature (though still not "melted.") |
| Posted by: Jackal 2007-05-01 21:58 |
| #10 It would be nice to put the phat hogg Rosie in a steel mill. You'd have to have a drip tray under her to catch all the rendered phatttt. |
| Posted by: Woozle Elmeter2970 2007-05-01 18:16 |
| #9 barbara, the other women where no match for the 300 lb beast. hell the men on the set would have had a hard time whooping her loud mouth ass, much less if you argued she would just talk longer |
| Posted by: sinse 2007-05-01 17:22 |
| #8 Why are so many people intellectually incapable of understanding that the supports are already under great stress because they are maintaining the structure and if weakened by fire can collapse suddenly and powerfully? Is it total ignorance of physics (acceleration is constant downward even when velocity is zero) or just an irresistable lust to believe in conspiracy theories? |
| Posted by: Grumenk Philalzabod0723 2007-05-01 16:59 |
| #7 The truly pathetic thing is that the other Oh, wait.... |
| Posted by: Barbara Skolaut 2007-05-01 16:43 |
| #6 The closest Rosie has come to molton steel is a good time with a stainless steel dildo. Even then, she tried it on backwards. |
| Posted by: wxjames 2007-05-01 15:14 |
| #5 I heard that too JAB. I never could stand her either. She's whiney and I never did think she was funny. Just crass. |
| Posted by: Deacon Blues 2007-05-01 15:13 |
| #4 Off topic but I read Rosanne Barr is the ABC favorite to replace Rosie, whose contract demands were too high. Is there some rule on that show that a loudmouthed, fat, leftist comedienne is required? What does this say about the viewers? |
| Posted by: JAB 2007-05-01 12:43 |
| #3 I wonder if Rosie has ever worked in a steel mill? Or watched a story about it on the History Channel? Or driven through Gary on the Indiana Toll Road? Or, . . . Never mind. |
| Posted by: Sonny Gloluth5441 2007-05-01 12:12 |
| #2 One other thing, when a steel beam gets hot enough it starts to sag. The more it sags the greater the stress on the connectpoints. They will fail. |
| Posted by: Deacon Blues 2007-05-01 11:45 |
#1 It doesn't need to melt. As my brother, the PhD puts it:All you have to do is weaken the bolts that hold the trusses to the verticle beams. That doesnÂ’t take long at all nor does it take a temperature anywhere near the melting point of steel. There is a Martinsitic phase transformation several hundred degrees below the melting point. It is a displacive transformation, which means it will cause buckling of the beams and bolts. Once that happens, buh-bye. Steel expands 1.2 cm per meter at 1000 degrees. A ten foot I beam becomes 3.6 cm longer, about an inch and a half. No rivet or bolt is designed with that sort of give. |
| Posted by: Chuck Simmins 2007-05-01 10:07 |