Experimental and numerical dynamic analysis of laminate plates via Carrera Unified Formulation

This work consists on evaluating potentialities and limitations of finite element formulations developed via CUF to predict free vibration response of laminated composite plates by using real experiments. Therefore, finite elements were developed via Carrera's Unified Formulation (CUF) for laminated plates, which were implemented as a FORTRAN subroutine (UEL - User Element subroutine) linked to commercial finite element software ABAQUS (TM), to simulate free vibration of composite laminates. In addition, laminated plates made of composite material, resin epoxy and carbon fibre, with two different layups, were submitted to experimental vibration tests. The experimental tests were carried out by using an impact hammer, which excited the structure with impulse signal, and accelerometers, which measured the output data. Dynamic characteristics, such as natural frequencies, mode shapes and Frequency Response Functions were presented for the specimens. Then numerical results were compared to real experiments, discussing different aspects of the formulated finite elements. In addition, there is a demonstration how to connect native finite elements from ABAQUS (TM) to elements formulated via CUF (using UEL subroutines) and how to solve this problem using numerical time integration algorithms implemented in ABAQUS (TM), including discussion about the influence of time integration parameters on the dynamic response.