DEVELOPMENT OF THE CONSTITUTIVE OPERATOR FROM THE EULER-PROBLEM TO LOCALIZATION

摘要

The constitutive operator has a crucial role in the tangent stiffness, consequently, in the stability of structures. The development of the constitutive operator has a long history. The literature and research on this field is very large, extended and ramified. Recently the strain softening cases, damage and localization are in the focus of research. However, the effect of constitutive operator is modified if the nonlinear properties of other state variables are also considered. In this paper a brief summary of the history and development of the constitutive operator is presented. Then, the effect of this operator embedded into the structural tangent stiffness matrix is analyzed, under the influence of other structural nonlinearities. The paper is closed by numerical applications.