Research On Anti-rutting Performance Of Medium-grained Asphalt Mixture At High-temperature

Rutting is a major distress found in high-grade asphalt pavements. Rutting causes into a lower road safety, comfort, and further leads to other road damages.The generation of the rutting is mainly due to shear deformation of asphalt mixture, while the compaction deformation is only a small part of the permanent deformation.Ring Road tests has showed that the main component of permanent deformation of road is the medium-grained asphalt mixture in surface layer,so this article has only researched on high temperature performance of medium-grained asphalt mixture . According to research needs, some improvements in domestic rutting instrument had been done so that it can be workable in rutting test at different temperatures, different rounds of pressure and different speed, and then the regularity of rutting depth and regularity of dynamic stability changing with temperature, wheel pressure and speed had been studied. The permanent deformation which Rutting Testing Machine measureed is central Permanent deformation of the specimen center,. So this article deduced the speed of rubber whell when it reached to the center of specimen. It also had made Significance Analysis on High Temperature Stability in conditions of multi-factors including temperature, wheel pressure, driving speed. Four levels of each factor were taken and orthogonal Tab. was used in orthogonal test, which showed that when test conditions were changing within standard scope of these factors, the orders of the impacts of temperature, loads and driving speed on dynamic stability and rutting depth were: temperature, speed, and then loads.After the systematic analysis of factors in rutting, rutting prediction model has been improved and the basic parameters of rutting prediction model have been determined through laboratory test and finite element calculations,based on the study of predecessors. Regression results showed that the rutting prediction model had a high accuracy, and rutting depth had a significant non-linear relationship with those various factors.As there were certain differences in conditions between the actual road and the laboratory, the actual status of permanent deformation of road did not been accurately reflected. This paper has used medium-grained asphalt mixture permanent deformation data measured in Ring Road test to amend rutting prediction model , and it also predicted the permanent deformation of the medium-grained asphalt mix in actual road. L16( 45)...