The complete solidification time of concrete usually depends on various factors, such as the mix proportion, temperature, humidity, etc.
Generally speaking, concrete will initially harden within 24 hours and reach strong strength after 72 hours, but it usually takes 28 days to fully solidify and reach the design strength.
This is because the hydration reaction of cement requires a certain amount of time to fully proceed, and as time goes on, the strength of concrete will gradually increase.
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