Development of a rutting prediction model for asphalt pavements with the use of an accelerated loading facility

Integrating the design of a pavement structure and its materials is fundamental to ensure that asphalt pavements possess adequate rutting resistance. In this study, a rutting prediction model was established to link mixture permanent deformation with pavement rutting in the process of integrating design. Several factors, such as the application environment (temperature and vehicle speed), service life (traffic volume), pavement structure, and mixture performance, were characterised. An exponential model was used, and a basic rutting prediction model was developed; the latter model involves mixture dynamic stability, shear stress of the pavement structure, axle loading repetitions, pavement temperature, vehicle speed, and pavement depth. Three different pavement structures were analysed through accelerated pavement rutting tests with an accelerated loading facility and through shear stress calculation. The corresponding asphalt mixtures were tested through rutting and creep tests on the asphalt mixture performance tester to determine the parameters of a simplified rutting prediction model with a reference speed of 20 km/h. A model of time hardening creep and loading time function was used to determine the relationship between pavement rutting and vehicle speed. The final rutting prediction model was established through adjustment of vehicle speed in the simplified rutting prediction model. An application method for the prediction model was also proposed through reference to rutting nonlinear superposition methods in the Mechanistic-Empirical Pavement Design Guide. Finally, the developed model was validated with the use of actual rutting data. However, more field rutting data are needed for further model validation and improvement.