" wrote:

Concrete cures to it's full hardness in 28 days assuming proper
conditions (temp., proper watering, etc).

Are you sure you don't mean nominal hardness? I thought that
concrete normally kept hardening for years, asymptopically
approaching some ultimate value, and that the 28-days was just
the standard to which they test the stuff.. So that 5000psi concrete
is called that because it hardens to 5000psi in 28 days...

--Goedjn

That is correct. With most types of concrete, it cures to its rated
capacity in 28 days. It will continue to cure for about 100 years,
according to the experts. Some types are different (high-early
comes to mind, but for the most part, 28 days is the norm.

--
Robert Allison
Rimshot, Inc.
Georgetown, TX