hecter wrote:I don't think so. Correct me if I'm wrong wicked, but much of a concrete bridges support would come from the steel re-enforcement bars buried in the concrete. These bars are essential to the bridges structural integrity. As the bridge ages, cracks may form and water seep in. If this water gets to the re-enforcement bars and corrodes them enough, then the bridge could just collapse. So it's hard to see that a bridge may collapse if it's all in the inside. The odd part, as previously stated, is the fact that the whole bridge fell at once, instead of just a section of the bridge.
Then again, that's just from my stoopid and unedjemacated self. I imagine we'll have wicked in here telling me how dumb I am any minute now...
*sits and waits to be yelled at by wicked*
*YELL*
ok now that that's out of the way...
Concrete is only strong in one direction (when compressed), hence the addition of steel rebar to support it under tension. Yes, cracks can occur and weaken the rebar.... exposed rebar is baaaad since steel exposed to water and air = rust. This would be evident on an inspection however. I believe that bridge was inspected yearly, but not sure of the date of last inspection. Normally bridges are inspected every two years, bad bridges and/or bridges that carry a lot of traffic may be instected every year, REALLY bad bridges, e.g. the Alaskan Way Viaduct in Seattle, are inspected every 6 months. If a center column collapsed, which is what I'm *guessing* happened here, it would explain the multiple sections of bridge collapsing at once.
Posted: Thu Aug 02, 2007 9:39 am
that was actually one of the reasons I was hired in my current job, to translate geekspeak for the general stupid public. 
