Originally Posted by tfd1224
Originally Posted by Solo
Originally Posted by TexasNative
I don't know, but look at how long the Egyptian pyramids have lasted. When I toured Hoover Dam, they made a comment about how long the dam would last barring an earthquake or other natural or man made disaster.


The pyramids are made from solid stone rocks, not 1930’s industrial concrete.

My uncle told me this and I’m not really sure how true it is but in the Florida keys there is an old bridge and new bridge over every span of water between each Key. We were fishing the 7 mile bridge and i asked my uncle why they were always working on the pilings of the new 7 mile bridge and he told me that the concrete keeps eroding away and they keep having to replace it and i asked how the old bridge was still there. He told me that some German scientists came up with a formula for the concrete that was used on the old bridge and that it has never eroded and somehow the formula was lost and they have been trying to replicate it ever since and haven’t even come close. The old bridge was completed in 1912 and the new bridge was completed in 1982.


The problem is the reinforcing inside the concrete. Moisture to reinforcing causes the reinforcing to rust and expand spalling off the concrete and furthering the deterioration of the reinforcing and eventual failure. Obviously the salt in a brackish environment makes it exponentially worse. The older bridges SOMETIMES fared better because they typically used larger sections of Concrete.