ABSTRACT
Usually, four types of stress-strain relationships are considered in the geotechnical analysis after the geomaterial behaves in the nonlinear process. They are perfectly brittle-plastic (curve I), strain-softening (curve II), perfectly plastic (curve III) and strainhardening (curve IV) relationship as shown in Figure 1. Although the combinations of the above relationships are sometimes employed to analyze the complicated behaviour, they can be easily handled on the basis of the mentioned types.
