Am I the only person that finds it odd that someone would make an ARCH bridge where the arch is made out of steel?
The arch in an arch bridge is always under compression, and steel is not that great under compression. I think a small layer of steel reinforced concrete under the steel arches would have made that bridge last forever. There are stone arches that were built over 1000 years ago still standing, but thats because stone and concrete are great under compression. Steel arches are pretty much worthless and give you a false sense of security.
Anyone else feel this way?
2007-08-04 19:55:39 · 5 answers · asked by Anonymous in Science & Mathematics ➔ Engineering
You have a valid point, but concrete is a lot heavier than steel beams, and the Mississippi river bottom might not have been able to support that much weight. Too much sediment, etc.
A large steel arch bridge sounds like a cheap solution for a poor building site. It probably should have been done as a suspension or cable-stay bridge.
2007-08-04 20:05:43 · answer #1 · answered by lithiumdeuteride 7 · 1⤊ 1⤋
The bridge that collapsed the other day was a truss bridge, not an arch bridge.
And steel is fine in compression, it is not unusual for heavily loaded reinforced concrete structures to contain steel compression reinforcement.
Concrete tends to be cheaper, and the concrete itself doesn't "rust", but it still doesn't last forever, and if the concrete is damaged the reinforcing steel inside can corrode.
2007-08-05 07:50:48 · answer #2 · answered by tinkertailorcandlestickmaker 7 · 1⤊ 0⤋
Whoever told you that steel does not do well in compression must have been pulling your leg.
The columns in a big building may look like concrete but they are often steel beams encased in concrete. the concrete is not necessary for load carrying, but it has a more pleasing appearance. The engineering reason for the concrete encasement is for fire resistance.
as far as the bridge collapse is concerned, I think we would all be wise to withhold judgement until the cause of the collapse is determined.
2007-08-05 12:20:22 · answer #3 · answered by bignose68 4 · 0⤊ 0⤋
The bridge deck is under compression due to the camber of the deck between the piers, but I would think that the support members of the truss structure would be under tension.
Whether the design of the structure or maintenance issues are the cause of the collapse remains to be seen.
2007-08-05 03:39:31 · answer #4 · answered by Anonymous · 0⤊ 0⤋
i think someone blasted that bridge.
2007-08-05 02:59:10 · answer #5 · answered by The Game 3 · 0⤊ 5⤋