Abstract
A non-linear elasto-plastic relationship of geomaterials is presented incorporating the Coulomb's criteria, in which cohesion and angle of friction mobilized on the shear band are expressed as functions of plastic shear strain. A procedure is developed to decide these functions by analyzing the results of triaxial compression tests. The scale effect of geomaterials caused by localized deformation within the shear band is taken into account by using a smeared crack concept in FEM analysis. Finally, this FEM code is used for simulating the triaxial compression tests on specimens of different sizes and the bearing capacity problems of a foundation adopting meshes of different sizes. The results show that the load-settlement curve and localized defomation in the ground can be computed with reasonable accuracy using a larger finite elements than the speciment from which the geotechnical parameters are determined.
