2. Overview of Material Models for Structural Analysis

Modeling.

The modeling of a structure which has to be analyzed can be divided into three major parts: (1) the discretization of the geometry: the Finite Element mesh, (2) the modeling of the physical behavior of the materials which are applied in the structure, for instance concrete and reinforcing steel and (3) the modeling of the structural effects which influence the behavior of the structure, for instance large displacements or time-dependent behavior.

Structural behavior.

To make the discretization, the user needs knowledge of applied mechanics and Finite Elements in particular, but it is assumed for this part that the geometry of the structure has been discretized in a proper fashion. For the modeling of the physical behavior of the material, the user needs knowledge about the failure mechanisms which can occur in the structure. For instance, in concrete structures the behavior is mainly influenced by cracking and crushing of the concrete and yielding of the reinforcement. Structural effects are those phenomena which can influence the behavior of the structure but this depends for a large extend on the history of the structure.
In this chapter, firstly the modeling of various types of structures is discussed briefly to guide the user through this manual [§2.1]. The overview is not intended to be complete and the user is encouraged to use engineering judgment for the application of the available models in a field different from the ones discussed here. Secondly, an overview is given of the available options for each element family and for the embedded reinforcements [§2.2].