Coupling of heterogeneous kinematics and Finite Element approximations applied to composite beam structures

In the framework of the modeling of composite beam structures, the eXtended Variational Formulation (XVF) is carried out to couple different kinematics. The purpose is to take advantages of efficient models and reduce the overall computational cost without loss of local precision. In this way, the structure is divided into non-overlapping domains with different kinematics. Local domains of interest are described with advanced models, such as refined Sinus model, to precisely describe local behavior, while the remaining global domain uses simple classical models. Each of the kinematics needs a suitable Finite Element (FE) approximation, therefore the coupling of different FE approximations is also addressed. The present approach is assessed on homogeneous and sandwich structures. It is compared with classical Multiple Point Constraints vias penalty. The study has shown the need of the introduction of a new operator for the layered structures. The results are very promising.