Three types of rigid body movements are considered in the analysis. These are translation, rotation about top (RT) and rotation about bottom (RB) modes as shown in Fig. 2.7 below.
Case 1: Active earth pressure
Case 2: Passive earth pressure
Fig 2.7 different movements of the wall under active and passive conditions
is the displacement at any depth Z and is the amount of displacement required for full mobilization of active earth pressure. is found to be 0.1% to 0.4% of D for dense to loose sands where D is the total height of the retaining wall. The displacement at the base of the wall is denoted by for RT mode and the displacement at the top of the wall is denoted by for RB mode.
is the displacement at any depth Z and 
is the amount of displacement required for full mobilization of active earth pressure. 
is found to be 0.1% to 0.4% of D for dense to loose sands where D is the total height of the retaining wall. The displacement at the base of the wall is denoted by 
for RT mode and the displacement at the top of the wall is denoted by 
for RB mode.
