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Thermal Stress

In a pre - te...

Question

In a pre - tensioned beam, the ultimate shrinkage strain and ultimate creep coefficient are $250 \times 10^{- 6}$ and 1.6 respectively. Given $E_{s}$ and $E_{c}$ are 210 GPa and 35 GPa, respectively. The stress in concrete at the level of steel, considering loss due to creep as two times the loss due to shrinkage, is equal to ________ $N / m m^{2}$ .
10.94

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Solution

The correct option is A 10.94
Creep loss $(ϕ m f_{c})$ = $2 ε_{s c} E_{s},$

= 2 x shrinkage loss $(ε_{s c}, E_{s})$

$\Rightarrow 1.6 \times \frac{210}{35} \times f_{c} = 2 \times 250 \times 10^{- 6} \times 210 \times 10^{3}$

$\Rightarrow f_{c} ≃ 10.94 N / m m^{2}$

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