Understanding of the ultrasound transmission in functionally graded structures materials is of great interest in many engineering applications such as geophysics, biomedical diagnostics, aircraft, and automobile. This paper will present a computational method and its implementation procedure to study the wave propagation problem in multilayer structures made from a combination of fluid, anisotropic viscoelastic, and poroelastic materials. The poroelastic material is described by using the Biot theory. The developed approach is based on the Semi-analytical Finite Element Method (SAFE), which only requires the discretization of the cross-section of the structure. For the finite element solver, high-order spectral element has been used, showing a significant improvement of the computational efficiency compared to the use of conventional high-order elements. Numeral validation in both time and frequency domains show that the proposed approach is efficient to investigate the transient response as well as the dispersion of layered media. Some results in the context of quantitative ultrasound axial transmission techniques for assessing properties of cortical long bones will also be presented.