送交者: BerkeleyBear 于 2005-7-26, 21:28:21:
回答: Berkeleybear also failed to mention there are steel bars in dams 由 Enlighten 于 2005-7-26, 17:44:27:
well, it is true that steel-reinforced concrete is a common sense to be used in a dam, especially in the upstream front.
But, in principle, tension stress should not be allowed in a dam. Although steel bar can compensate the tensile strength, we shouldn't count on it, because the concrete also cracks in this case -- that is very dangerous.
Your elementary school knowledge fails to recognize that the steel bar can provide tensile strength only when extended (concrete cracks at the same time).
It is more easy for an ignorant to criticize than construct.