Study On The Performance Observation And Forecast Of Flexible Base Asphalt Pavement

For a long time, pavement structure of highway in China is relatively simple, which is semi-rigid base asphalt pavement structure, so that the single form of pavement structure is very difficult to adapt to the requirements from different areas in the country. The application of flexible base asphalt pavement enrich the structural forms of asphalt pavement and is also important for improving the durability and service level of China’s highway network.In this paper, a large number of the observed data ofthe flexible base asphalt pavement sections constructed during the last 9 years were collected and analyzed, including performance observation,field survey on pavement distress and rutting situation. This study compared flexible pavement and semi-rigid road surface performance and evaluated the adaptability of flexible base asphalt road to transportation and climate conditions. At last, the typical diseases of asphalt pavement with flexible base structure were analyzed. Based on the core sample thickness, porosity, gradation, bitumen aggregate ratio, asphalt performance index of the test,the reason of flexible base asphalt pavement rutting and layer composition and development of the situation were investigated. Master curves of dynamic moduluswere made for the asphalt mixture from Wuxi section of Huning Expressway. Based on the dynamic modulus mechanical analysis of flexible base asphalt pavement structure was conducted, effect of traffic axle load onflexible base asphalt pavement structure durability was analyzed. At mean time, this study provided fundamental data for further performance prediction. Based on continuous observation datafrom the flexible base structure in Wuxi section, the fatigue and rutting performanceof flexible base asphalt pavement of were predicted. By using the mathematical statistics method and the measured the rutting data of flexible pavement in the Wuxi section in both Nanjing to Shanghai direction and Shanghai to Nanjing direction, the MEPDG rutting prediction model was modified and verified. Finally, the revised coefficients for local area and the rutting prediction model were obtained.