Study On Distress Diagnosis And Maintenance Decision-Making Of Expressway

Since the reform and opening-up policy was carried out, the expressway in China has developed rapidly and by the end of 2010, the total mileage of expressway has reached 74,000 kilometers. With the development of economy and the contradiction between the decreased pavement condition and the increased desire of pavement service, the maintenance and management of expressway focused on how to keep a good pavement service condition by carrying out appropriate maintenance. What is more, accurate disease diagnosis and scientific conservation decision-making become the key issues in the maintenance of expressway.Jinan-Qingdao (JQ) expressway, which is constructed in 1993, is the first expressway in Shandong Province, keeping a good pavement condition. The maintenance and management of JQ expressway has a good reference to other expressways. Based on the project of "Research on asphalt pavement maintenance and management of JQ expressway in Shandong Province", this paper summarized and analyzed the maintenance and management of JQ expressway.By analyzing the structural features and performance evolution of semi-rigid pavement, this paper further studied the relation between the distress development and structure working condition. Then, an appropriate distress diagnosis method, which is called three-stage distress diagnosis method, was proposed to make the distress diagnosis dynamic.The paper also discussed the semi-rigid asphalt pavement maintenance decision-making and design of disease, proposed a new decision-making idea of distress repair, systematically analyzed the repair strategies of the semi-rigid asphalt pavement in the different periods and studied the maintenance idea of partial repair and overall overlay.Considering the fatigue damage and decreased strength parameters of semi-rigid pavement, this paper used the finite element software FLAC 3D to analyze mechanical response of pavement structure under vehicle load, and then proposed a solution for this problem.In a word, how to accurately diagnose the reason of pavement distress and its development trend and how to scientifically make maintenance decision to carry out effective and appropriate maintenance play a significant role in the maintenance and management of expressway.