SPRING, $2024$

PROBLEM $1$

A concrete, which reaches the maturity for demolding at $20C$ in $7$ days, was exposed to ambient conditions with a temperature of $16C$ for $16$ hours and $6C$ for the rest of the day for $3$ days and $10C$ for $16$ hours and $-1C$ for the rest of the day for $4$ days, respectively.

a$)$ Determine the total time required for demolding if the concrete is assumed to be exposed to ambient conditions with an average temperature of $16C.$

b$)$ Determine the compressive strength of concrete for each maturity degree and $k_2=6\mathrm{.}6MP\frac{a}{}C.$ days