• Gravity Wall: Relies on its own massive weight to resist overturning and sliding.
• Cantilever Wall: Reinforced concrete wall (stem and base slab) using the weight of the backfill.
• Sheet Pile Wall: Flexible steel sheets driven into the ground.

Factor of Safety ($FS_{ot}$) against rotation about the toe. $FS_{ot} = \frac{\sum M_R}{\sum M_O} \ge 2.0$

• $M_R$: Resisting moments (Weight of wall/soil).
• $M_O$: Overturning moments (Lateral earth pressure).

Factor of Safety ($FS_{sliding}$) against horizontal sliding. $FS_{sliding} = \frac{\sum F_R}{\sum F_d} \ge 1.5$

• $F_R$: Resisting force ($R \tan \delta + c_a B$).
• $F_d$: Driving force (Horizontal component of $P_a$).

The maximum pressure exerted by the base on the soil ($q_{max}$) must not exceed the allowable bearing capacity ($q_{all}$). Eccentricity check: Resultant must be within the middle third ($e < B/6$) to avoid tension.