Developing an Asphalt Pavement Preventive Maintenance Program for theYangjang-Maoming Expressway

Yangjiang-Maoming Expressway is located in Guangdong Province, and is part of Tongjiang-Sanya highway, which serves as the main trunk highway from north to south China. This expressway was completed and opened to traffic near the end of 2004. After four years of use, the general condition of the pavement is good. However, some cracking was observed. Meanwhile, some potholes and rutting were also found in some pavement sections. As a result of the surface deterioration, a pavement preventive maintenance program was considered necessary to avert structural damage. The agency of Yangjiang-Maoming Expressway partnered with South China University of Technology, in Guangzhou, to design a preventive maintenance program for asphalt pavements. This paper will summarize the process of creating a preventive maintenance program for asphalt pavement in the following sequence: (1) Survey and evaluation of asphalt pavement performance. Four indices, including pavement condition index (PCI), riding quality index (RQI), pavement structure strength index (PSSI) and slip resistance index (SRI) were measured and evaluated. A pavement condition database was obtained based on field survey and historical data review of a 1000 m (3,280 feet) long pavement section as the basic evaluating element. The result of the analysis showed that transverse cracking and skid resistance were the most severe problems. (2) Grouping of candidate sections and selection of treatment. For a pavement maintenance project, it was expected that the candidate sections to be treated, were as long as possible to avoid frequent mobilizations of paving equipment. Thus, it was necessary to group sections with similar features and like treatments. To this end, the cluster analysis method of gathering statistics was used. Three pavement condition groups exhibiting different distress types and severities were obtained, corresponding to different maintenance treatments respectively. In addition, multivariate analysis of pavement distress indices indicated that transverse cracking and rutting significantly influence PCI, and there appeared to be a correlation between the two indexes. (3) HMA pavement performance modeling. According to existing research, the deterioration of pavement performance conforms to the S-shaped curves. The regression method is used to create deterioration models. The errors of prediction results versus actual data are less than 0.05%, which indicates that these models have good applicability and stability. (4) Pavement asset management. The concept of asset management was introduced to determine the minimum annual program cost and treatment costs to keep the asphalt pavement in good condition and extend the design service life. In this research project, the preventive maintenance program is recommended, based on the distress patterns of asphalt pavement with semi-rigid base and deterioration of the pavement structure. Considering that more than 80 percent of HMA pavements are constructed on a semi-rigid base in China, this project is of great significance in improving existing pavement performance and extending pavement service life by using cost effective methods.