The coefficient of thermal expansion for steel is 0.00000645in/in/deg. Doesn't sound like much, but for a 100' piece of pipe, the difference between a -20F day and a 110F day is 1". Aluminum expands twice as much as steel. Concrete is practically identical to steel. (Convenient for rebar, eh?) BUT, if that concrete has expansion joints, and the steel doesn't...
PVC is far worse, as it has a much higher coefficient of expansion. A similar piece of RNC would have an appx 4.5" expansion/contraction.
Last edited by SteveFehr; 11/20/07 01:45 PM.
