Engineering and Construction

In order for the active wedge to be developed, there must be sufficient movement of the retaining wall. There are many cases where movement of the retaining wall is restricted. Examples include massive bridge abutments, rigid basement walls, and retaining walls that are anchored in non-yielding rock. These cases are often described as restrained retaining walls.

For earthquake conditions, restrained retaining walls will usually be subjected to larger forces as compared to those retaining walls that have the ability to develop the active wedge. Provided the soil is not weakened during the earthquake, one approach is to use the pseudostatic method in order to calculate the earthquake force, with an increase to compensate for the unyielding wall conditions, or: