The heat from the fire will cause steel beams to expand. Two things can happen, first the expansion can cause walls to be pushed outward and fall. Second, after the fire, beams can contract as they cool and fall within the supports that got pushed outward, so, be careful during mop up.
This was taught in firefighting training I had many years ago and I suspect better building methods are used now days. Any of you engineer types have a way to find out how much expansion a 100 foot beam could generated in a building fire? The answer was part of the training but I can't recall. Harry On Mon, Jun 30, 2008 at 9:51 AM, Royce Engler <[EMAIL PROTECTED]> wrote: > > Mitch Haley wrote: > > Somewhere I've got a picture of a burned out barn with steel beams > drooped > over a wooden > > beam. > > If you read the article that Mitch referenced, you'll see further down the > difference between a glue-lam wooden composite beam and a steel > beam...making the point that steel can and does fail before some wood > structures. > > I did some googling and found the following excellent discussion by a fire > department expert. Based on my somewhat limited knowledge of structural > engineering (I'm a petroleum engineer by training, but I had to take all > the > same core courses as the structural guys, and I my Dad was a structural > engineer), this guy knows what he is talking about. One of his points is > that the steel trusses were the weak points, and all fire departments know > that. Once one part of a truss fails, the rest of the truss can fail > quickly as undamaged parts have to pick up the loads of other parts that > failed. He also mentions the problems with failed insulation on the steel, > I have seen mentioned several times in discussions about WTC. Of course, > that was partially due to issues with asbestos, and you can just imagine > the > restrictions in NYC for dealing with asbestos. > > Bottom line, I'm tired of hearing about "conspiracies" other than the one > where 19 terrorists climbed on board undefended airliners, slit the throats > of women, and bravely drove those planes into buildings that housed over > 3000 civilians. > > As an aside...we're visiting in-laws in Oklahoma City and yesterday went to > the site of the 1995 bombing. I'm sorry they executed Tim McVeigh....I > would rather they caged him up and kept him at the site so people could > kick > his ass. > > Royce > > > _______________________________________ > http://www.okiebenz.com > For new parts see official list sponsor: http://www.buymbparts.com/ > For used parts email [EMAIL PROTECTED] > > To Unsubscribe or change delivery options go to: > http://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com > _______________________________________ http://www.okiebenz.com For new parts see official list sponsor: http://www.buymbparts.com/ For used parts email [EMAIL PROTECTED] To Unsubscribe or change delivery options go to: http://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
