Question $3(5$ points$)$

The $1\mathrm{.}35$ m concrete post is reinforced with six steel bars, each with a $28$ mm

diameter. Knowing that $E_S=200$GPa and $E_C=29$GPa, determine the normal

stresses in the steel and in the concrete when a $1560$ kN axial centric force $P$ is

applied to the post.

${}_5=60$MPa,${}_c=10$MPa

${}_s=59\mathrm{.}5(C)MPa,{}_c=8\mathrm{.}6(C)MPa$

${}_s=60\mathrm{.}3(C)MPa,{}_c=9\mathrm{.}1(C)MPa$

${}_5=59\mathrm{.}5(C)MPa,{}_C=8\mathrm{.}1(C)MPa$