Modal properties investigation of a carbon/glass fiber-reinforced polymer composite sandwich structure with lozenge-like core: An experimental and finite element simulation

Abstract

The vibration properties of a carbon fiber-reinforced polymer (CFRP) and glass fiber-reinforced polymer (GFRP) composite sandwich panels with lozenge-like core and free-free boundary conditions are experimentally determined in this research. The sandwich panels manufactured for this study are composed of CFRP, GFRP, and epoxy resin. A modal experiment is performed using a modal hammer with an acceleration sensor to obtain modal properties of the structure, including natural frequencies, damping ratio, mode shapes, and frequency responses. Eventually, the comparison of vibration characteristics of the CFRP sandwich panel with the GFRP sandwich panel with almost identical geometry is discussed in detail. Furthermore, a finite element simulation is developed to validate the precision of the experimental data. It is recognized that the finite element results are in remarkably good agreement with those obtained by modal experiments. Hence, the finite element analysis and experiment method could be utilized to predict the modal properties of the CFRP and GFRP composite sandwich panels.