Research Information System
SABUNCUOĞLU B. (Executive)
TUBITAK Project, 3001 - Initial R&D Projects Support Program, 2018 - 2020
Composite materials are heterogeneous materials, which are generated by the combination of two or more materials. As in many materials, finite element method is the common choice to model these. Homogenization of the material properties is the usual approach in modeling of these materials. However, this approach is valid in many assumptions. On the other hand, it does not allow investigation of the stress and strains in component materials. For realistic modelling these materials should be modeled separately. However, this causes problems in meshing and existence of many elements during finite element modeling in case these component materials have complex shapes. In order to resolve this issue, embedded element method was developed. Int his method, the component materials are meshed separately as embedded and host regions. Constraint equations are defined between these materials in order to make these component materials behave as a single material. By this method, the continuity in the elements are not needed resulting in a proper and fewer elements. Besides, realistic modeling of mechanical behavior is achieved by direct modeling of materials instead of empirical formulations. The stress and strains on the component materials can also be investigated. However, in order to achieve realistic results, in addition to need for the relative size of embedded regions being smaller than the host region, the host materials should show linear elastic material behavior. Because the host material in the embedded material region still exists (redundant volüme) affecting the mechanical behavior. In composites, the most common host material (matrix) are thermo-elastic and thermos-plastic polymers. In addition, the mechanical behavior of muscle and tissue materials are non-linear as well. When the embedded region ratio increases, including this nonlinearity becomes important
The aim of this Project is to develop a methodology to for the embedded element method to be used for elasto-plastic and inelastic materials. This will be performed by including the effect of redundant volume, which prevents the realistic modeling. Due to the nonlinear material behavior, the material properties of the redundant volume will change in each point in the material and in each loading step. Thuds, after each analysis step, the results of redundant volume will be included in the next step to update the material properties of embedded region according to their position. The procedure results, which needs complex user subroutines, will be compared with classical continuous element method. The applicability of the method will be discussed via sample problems.