Problem $1(20$ points$)$: A square foundation is $2\mathrm{.}5m2\mathrm{.}5m$ in plan. The soil supporting the foundation has a friction angle of $\frac{O}{{?}^{\text{'}}}=28$ and $c^{\text{'}}=24k\frac{N}{m^2}.$ The unit weight of soil, $,$ is $17\mathrm{.}0k\frac{N}{m^3}.$ Determine the allowable gross load on the foundation with a factor of safety $($FS$)$ of $3$ using equation $(4\mathrm{.}26).$ Assume that the depth of the foundation $(D_f)$ is $1\mathrm{.}0$ m and that general shear failure occurs in the soil.

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