Effect of Wall Movement on Active and Passive Pressures

The normal and shear components of the active and passive thrusts depend on the direction and magnitude of wall movement as well as the soil properties and the geometry of the structure. Use has been made of the theory of plasticity for a rigid-plastic associated or nonassociated flow rule material to predict the relationship between the thrust and the direction of wall movement. The study embraces all possible active and passive states for translatory movements. For the special case of a positive or negative rough soil-wall interface, one set of velocity characteristics are tangential to the interface and this defines the interfacial stress state. A comparison between traditional methods for determining the active and passive thrust with the lower bound plasticity solution shows that there is little disagreement in numerical values. For wall translation requiring a continuous stress field, the lower bound solution is also the correct solution for an associated flow rule material.