Abstract:
To provide a reference for the reduction analysis of pavement performance, an asphalt pavement with different base types was taken as research object in this study to evaluate the feasibility of the dynamic backcalculation in pavement performance reduction. The field deflection measured at 2010 and 2015 was backcalculated by using dynamic and static approaches to study the various tendencies of the layer property during the service life. The spectral element method was adopted in the dynamic approach to conduct dynamic viscoelastic analysis and the deflection time-history was used to construct the optimization objective function. The complex modulus of asphalt layer and the elastic modulus for other layers were obtained. The layered elastic theory was adopted as forward analysis engine in the static method, and the deflection basin as constrain in the optimization process, and the elastic moduli for all layers were obtained. The dynamic backcalculated layer property was employed for pavement analysis under moving vehicles. The strainress at the bottom of the layer and the vertical strain at the mid depth of the asphalt layer were calculated to study the various tendencies of response within service life. Result shows that the layer property from static approach is fluctuant, and the result of 2015 is even greater than that of 2010. The dynamic backcalculated layer property is more stable, and its tendency can objectively characterize the pavement performance reduction. The analyzed response based on dynamic backcalculated layer property shows reasonable variation and it is consistent with the layer property. The deflection time-history can provide more constrains in optimization process, which can be efficient to avoid the error of static approach due to the modulus compensating phenomenon. The research provides an efficient and convenient routine for pavement performance reduction analysis.