In the present paper, thermo-viscoelastic constitutive equation of carbon fiber reinforced plastic is investigated by numerical approach based on finite element method(FEM) and homogenization theory. The constitutive equation of the CFRP is considered on the Laplace-transformed domain, and it is discussed based on correspondence principle which is satisfied by the each Laplace-transformed elastic moduli. Homogenization theory is employed to estimate the 'homogenized elastic moduli' of the composite composed of matrix resin and carbon fibers. Using approximation of generalized Maxwell model, the relaxation modulus of CFRP is obtained by numerical computation with FEM. The effect of the volumetric loading rate of the carbon fiber and the individual elastic moduli of the fiber and matrix on the estimated relaxation moduli are discussed from the results of numerical demonstration in detail.
