عنوان مقاله [English]
In this paper, the behavioral properties of soil beneath and around foundations, including interaction between the soil and the foundation, are studied numerically. To achieve this purpose, two dimensional models with a constant domain under a uniformly distributed load for both large and small foundations have been analyzed using ANSYS software, version 8.1. The results of this analysis clearly show that soil behavior beneath and around small foundations is shearing, which is the same as the predicted behavior and accepted failure mechanisms that most researchers believe in.However, based on results obtained from this research, the earth located in central areas, as well as under large foundations, is mainly under compressive and comprehensive stresses having a hardening plastic behavior. Consequently, the bearing increases and, hence, stress concentration, as well as
deformations, are towards this region. With respect to the fact that loading is constant, regions outside the foundation beneath (the sides) undergo unloading (localization). Thus, the failure mechanism in large foundations is in the form of the interior, as well as forming a resistant and bearing column beneath the foundation. In other words, soil behavior and properties will change as the foundation geometry changes.Accordingly, with regard to geometry increase, as well as type of soil, as behavioral features change, the stiffness matrix will change also, which will be in the form of coupled.