Out-of-plane moving load response and vibrational behavior of sandwich curved beams with GPLRC face sheets and porous core

As a first endeavor, the out-of-plane free vibrational behaviors and moving load responses of sandwich curved beams with graphene platelets reinforced composite face sheets and porous core (GPLRC-FS-PC) are carried out. The governing equations are derived based on the first-order shear deformation theory (FSDT) using Hamilton's principle, which are discretized by employing the differential quadrature method (DQM) and Newmark's method in the spatial and time domains, respectively. To simulate the moving load using the DQM, the Heaviside function approach is utilized. The effective elastic properties of face sheets are estimated using Halpin-Tsai micromechanical model. The approach is validated by presenting convergence studies and accuracy verification followed by parametric studies. The numerical results indicate that by adding little amount of graphene platelets (GPLs) into the face sheets and core layer, the fundamental natural frequency and the displacement amplitudes under moving load significantly increases and decreases, respectively, regardless of the beam boundary conditions. It is revealed that the GPLs distribution patterns in face sheets and the core porosity distribution patterns affect the critical load velocities of the GPLRC-FS-PC sandwich curved beams. Also, it is shown that the frequency parameters strongly depend on the face sheet to core thickness ratio.