$22,222$ psi

Practice Problem:

Hint: $=0\mathrm{.}005"$ as that's the max elongation, $L=24",$ Modulus of Elasticity $(E)=29,000,000$

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A square concrete column has a cross$-$sectional dimensions ${15}^{\text{'}\text{'}}{15}^{\text{'}\text{'}}$ and supports a total vertical load of $450,000lbs.$ Calculate the direct compressive stress at any point in the column.

If the column reduces in length by $0\mathrm{.}2$ inches as a result of the loading and the column's original length was $12$ feet, calculate the strain in the column.

Solution

Hint: The column is clearly in compression.

The column's cross$-$sectional area, $A={15}^{\text{'}\text{'}}{15}^{\text{'}\text{'}}$

Axial load $P=450,000lbs$

Compressive Stress $()=$ Force $\frac{?}{?}$ Area $=$

Strain $()=\frac{}{L}=$

Original length $(L)12ft$

$($Remember: strain has no units.$)$