I'm having a hard time quantifying cost of precast (High f'c, fly ash in mix) vs Cast In place. I have done a lot of research but can't seem to find a decent answer.
What item do you want to compare?
That can make a huge difference in cost. For example, a precast bridge slab is "cheap" compared to a similar cast-in-place bridge slab (which requires site-based elevated formwork & extensive field labor).
Answers you get on this site, from engineers in different parts of the world, won't be of much help. Precast and cast in place concrete are essentially two different materials, and their comparative usage and economy vary greatly from place to place. You need to research your locale, not the internet.
Respawn - There is a way to get a clue... if precast is readily available and widely used in a certain area, it must be at least cost competitive with cast-in-place or it would not be manufactured. Then talk to others as suggested.
If precast cannot be found, cast-in-place has the cost advantage.
and if you have a kazillion different parts, you use precast like they did for the Montreal stadium... I never did understand that. You have to have a high repetitive number of the same item.
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