Abstract：The data of field monitoring were used to analyze the affection of various factors. It concludes the dynamic stress distribution discipline in layered road system. Based on the existing elastic multilayer theories，using methods of transfer matrix and viscoelastic equation，the dynamic response of three-dimensional layered road system was obtained. Finally，the result，which was calculated by Matlab matrix numerical analysis software，was compared with the data of field monitoring test. Based on the above analysis，FLAC3D，the program was compiled for dynamic response of multi-layer road system under traffic loading. This program was used for three-dimensional numerical analysis of multi-layer road system，the distribution discipline of dynamic stress and dynamic displacement has been analyzed. At the end，the result was compared with the data of field monitoring to verify the effect of the program. the results indicate：(1) dynamic additional stress decreases quickly and the rate of attenuation tends to smooth as the depth increased；(2) dynamic additional stress is diffused effectively and significantly by the upper layers；(3) vehicle vibrating causes stronger dynamic additional stress than that without vibration；and (4) dynamic additional stress has accumulative effect.
