Study on Damping Characteristic Parameters and Dynamic Deflection Distribution of Asphalt Pavements

Abstract

To attain the data of effective dynamic deflection basin utilized to implement modulus backcalculation of asphalt pavement, by dynamic finite element method, the solution method of damping coefficients of pavement structural layers is discussed, the estimation model of subgrade damping coefficients is established, and the influence of testing loading’s dynamic effect and discontinuous contact behavior between structural layers on distribution features of surface dynamic deflection basin is investigated. The results demonstrate that (1) subgrade damping coefficient is a main factor affecting surface dynamic deflection distribution, which is mainly controlled by subgrade modulus, while influence of other structural parameters on subgrade damping coefficients is negligible; (2) when the asphalt pavement is imposed by static and dynamic loadings, the distribution features of dynamic defection basin has a dynamic defection basin for the same asphalt pavement; (3) performing back calculation of modulus parameters of structural layers should consider the actual FWD loading characteristics and the interface contact behaviors.