Using finite element nonlinear analysis, the dynamic soil pressure on perimeter retainingwalls of structures is investigated. Nonlinear Drucker Prager failure criterion is used to model the soilbehavior in the near field. The far field soil and the middle structure are assumed to behave as linearelastic materials. The soil-wall interface behavior is modeled incorporating nonlinear interfaceelem...

The theory of buildings, created by J. Tits three decads ago, has ooered a uniied geometric treatment of nite simple groups of Lie type, both of classical and of exceptional type. (See Tits 19] and 20] for an exposition of that theory; also Ronan 15] and Brown 1].) Diagram geometry (see 13] for an exposition) is a generalization of the theory of buildings. It has been invented by F. Buekenhout ...