Why do they make roads that cause porpoising?
Just got back from the "big" camping trip of the year. The last 5 or so miles on the East end of Interstate 490 in New York is fairly new concrete. My truck is nothing special, a regular cab long b...
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bhoat wrote:
We have a good section of concrete bridge near my house going over the intercoastal waterway. All vehicles porpose going over this.
I was told when they pour a section of I-Beam for the bridge, then place it, it will have an engineered pronation so when the top is poured, the weight will level out. Sometimes they are a little off.
Yep that happens on bridges sometimes. More so with concrete girders then steel as it is much more difficult to dial in exact camber with post tensioned concrete due to shrinkage and creep than steel with more consistent properties.
With concrete girders sometimes 100% of the dead load deflection is not taken out intentionally to account for additional deflection of service loads and time stress vs strain.
