Based on the dynamic response of the whole vehicle model and the elastic layered road model， the dynamic test area of highway is the distance of 0.4~0.8 m away from the contact point of tire-road. The influences of surface modulus， surface thickness and equivalent modulus of elasticity on surface strain and fundamental frequency are analyzed. The results are that surface strain decreases with the increase of surface modulus， surface thickness and equivalent modulus of elasticity. However， the fundamental frequency decreases with the increase of surface thickness， and increases with the increase of surface modulus and equivalent modulus of elasticity. The fitting formulas of surface strain at different distance away from the wheel outside， fundamental frequency， and equivalent modulus of elasticity are established. Finally， the feasibility and accuracy of methods in this paper is verified by comparing with measured values in field testing. The method provides a reliable foundation for highway testing and maintenance.