The overweight vehicles create complex moving vehicle loads described as dynamic, three-dimension non-uniformly distributed contact stresses between tire and pavement surface. But existing calculation models and methods for structure mechanics of pavement cannot analyze the mechanical response of pavement under complex vehicle loads. Based on the theory of three-dimension elastic dynamics, the above problems were solved by using multidimensional Fourier Transformation technique after transforming moving coordinates, and general solution for multilayer elastic system under complex vehicular load was derived in this paper. Then, pivotal issues were analyzed for numerical methods implementation. Lastly, the calculation results were contrasted with results of spot test, which showed that the mechanical responses model and its numerical methods implementation are reasonable and correct.