“…They include analytical approaches, 5,6,8 finite element method, 4,9 and spectral element method. 3,7,10,11 In the literature, the fast Fourier transforms (FFT)-based exact dynamic stiffness method is named spectral element method (SEM). 12 Because the exact dynamic stiffness matrix is formulated from the exact frequency-dependent (dynamic) shape functions, which satisfy the governing equations of motion, it represents the dynamic behavior in a structural element exactly.…”