1. The backfill is dry, cohesionless, homogeneous, and rigid material
with a uniform internal friction angle.
2. The wall yields sufficiently to mobilize the full shear strength of the
backfill along the potential sliding surface and produce minimum active
pressures.
3. The potential failure surface in the backfill is a plane that goes through
the heel of the wall.
4. The wall is long enough to make the end effects negligible.