A method for evaluating the resilient moduli of unbound granular materials is presented herein. The moduli were back-calculated from correlations of performance data of numerous full-scale accelerated traffic test pavements with computed critical stresses and strains of test pavements. The test pavements consisted of conventional flexible pavements as well as all-bituminous concrete (ABC) pavements. The loadings include single and multiple wheels. The stresses and strains in the pavement structures were computed by the finite element technique incorporated with the tried non-linear stress-strain relations of pavement materials. A general discussion on the nonlinear characteristics of pavement materials and limitations of the finite element computer program is presented. The parameters used to establish the correlations included (a) radial tensile strains at the bottom of the ABC, (b) maximum radial tensile strains and minimum ratios of radial tensile stress to vertical stress in the unbound granular layers, and (c) vertical strains at the subgrade surface. Parameter b was developed only for single-wheel loads. The principle of superposition was used in the computations for multiple-wheel load assemblies.