Practice Question: Calculate Modulus of Elasticity of Concrete

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Solution

Given:
\(w_c = 150 \text{ pcf}\)
\(f'_c = 4000 \text{ psi}\)

The modulus of elasticity \(E_c\) is calculated as:

\[E_c = 33w_c^{1.5} \sqrt{f'_c}\]

\[E_c = 33 \cdot 150^{1.5} \cdot \sqrt{4000}\]
\[E_c =3,834,254 \text{ psi} \approx 3,800\text{ ksi}\] 
 

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