$q_{u} = c N_c s_c + q N_q + 0.5 \gamma B N_\gamma s_\gamma$

• $q_u$: Ultimate bearing capacity.
• $c$: Cohesion.
• $q$: Effective overburden pressure at foundation level ($\gamma D_f$).
• $B$: Width of foundation.
• $N_c, N_q, N_\gamma$: Bearing capacity factors (functions of $\phi$).
• $s_c, s_\gamma$: Shape factors (1.0 for strip footings).

For a square footing of width $B$: $q_u = 1.3 c N_c + q N_q + 0.4 \gamma B N_\gamma$

$q_{all} = \frac{q_u}{FS}$ Typical Factor of Safety ($FS$) = 3.0.