Research On Technology Of Construction Quality Control For TLA Modified Asphalt Pavement

Now in high class of highway asphalt pavements there are many common distresses such as ruts, cracks and water damage. In order to ensure the performance requirements of high strength, stability, safety and durability for asphalt pavements, the application of modified asphalt became the main method. Therefore, combined with the asphalt pavement construction of the First Loop Expressway of Fast Main Highway of Foshan City, the paper developed the research on technology of construction quality control for TLA modified asphalt pavement. In view of the characteristic of TLA modified asphalt and considered the factors of local climate characteristic and traffic, the paper carried on the strict control to the links which could affect the engineering quality possibly and proposed the more reasonable control indexes. The indexes mainly included three aspects which were the quality of raw material, the mixture ratio design of asphalt mixture and the construction craft of asphalt mixture.1) According to the applied aggregate in the different function of structure layers and the different composition characteristic of the mixture, certain aggregate qualitative indexes were adjusted in order to make the standards to suit the local climate characteristic of Foshan Prefecture. The methods of preparation, transportation and storage of TLA modified asphalt were suggested. The adhesiveness between TLA modified asphalt and granite was enhanced effectively through mixing the cement and the anti-stripping agent.2) The mixture ratio of TLA modified asphalt mixture was designed. The pavement performances of TLA modified asphalt mixture were contrasted separately with the ordinary asphalt mixture. The result indicated that because of the mixed nature TLA, the high temperature stability, the water stability and the impermeability of the TLA modified asphalt mixture had improved distinctly under the same conditions of mineral aggregate and gradation. The TLA modified asphalt mixture was tested with the extraction method during the verification stage of the production mixture ratio. The influences of the ash content in TLA to asphalt-aggregate-ratio and gradation were analyzed.3) According to the construction of experiment road at the First Loop Expressway of Foshan City and the laboratory test results, the paper put forward one whole series of construction methods, key technologies, quality control measures and standards of TLA modified asphalt mixture. Through out the construction quality monitoring in the construction site, the compactive effects, the strength and the stiffness of pavement at the experiment road were examined and analyzed. The results indicated that the organization jobs were well done, the pavement quality and the pavement performances were fine during the construction. The application effects were good since the traffic was open for more than one year.