This lesson introduces the concept of lateral earth pressures and how geotechnical engineers compute them using lateral earth pressure coefficients. The differences between active, passive, and at-rest cases are explained. Rankine passive and active earth pressure coefficients are derived for cohesionless soil, and an example retaining wall problem is solved.

Learning Objectives:

1) Explain the differences between passive, active, and at-rest lateral earth pressure.

2) Compute the Rankine active and/or passive lateral pressure coefficient(s) for a given cohesionless soil.

3) Solve the equivalent lateral earth force (active or passive) acting on a wall, including the possibility for multiple soil layers, water behind the wall, and a surcharge on top of the wall.