ABSTRACT
In recent years the design in geotechnical engineering has come to be considered in terms of limit states. The introduction of this concept can be so viewed as to remind the designers that a soil structure must satisfy a certain number of requirements. Some of these requirements must be fulfilled not only during the life of the structure, but also during its construction, and when a structure or parts of the structure fail to satisfy one or more of the above requirements, one can say that a limit state has been attained. In a rather wide perspective, the three major requirements are those of strength, stiffness and stability, that means that the structure must safely carry the imposed loads, it must not deflect reaching critical displacements and it must not develop unstable displacements.
