Fatigue Life Research Of Polyacrylonitrile Fiber Asphalt Concrete Bridge Deck Pavement

Recently,asphalt concrete is widely applied in bridge deck pavement structure.As a direct force structure layer, its fatigue performance has an important influence onthe quality and service life of the bridge. But since the material properties of asphaltconcrete itself as well as the increasing traffic volume, early fatigue failure of asphaltconcrete bridge deck pavement is very common, it seriously affects the driving safetyand comfort, and cause huge economic losses. Because polyacrylonitrile fiber cangreatly improve the fatigue performance of asphalt concrete, polyacrylonitrile fiberreinforced asphalt concrete has been widely developed and applied in recent years.But, at present, the research of fatigue property of polyacrylonitrile fiber asphaltconcrete only limited to the material level, the research of the fatigue performance ofpolyacrylonitrile fiber asphalt concrete bridge deck pavement layer is rare. This paperwill carry out a systematic analysis and research on this with a65+100+65mcontinuous variable cross-section concrete box girder bridge. The main content of theresearch and results are as follows:Firstly, the paper presents the two commonly used methods of theory ofsurfacing layer fatigue analysis in detail, namely: the phenomenon based on only likelearning fatigue equation method and approximation method based on the theory offracture mechanics, through the comparison, this paper selects phenomenon based ononly like learning fatigue equation method for bridge deck pavement fatigueperformance analysis, and according to the test research results of domestic relevantresearchers we selected equation of ordinary asphalt concrete fatigue life andpolyacrylonitrile fiber asphalt concrete fatigue life.Secondly, in this paper a65+100+65m continuous variable cross-section beamelement model and solid model of concrete box girder bridge is built through thefinite element software Midas/Civil, and then determine the most unfavorable loadlocation by using the beam element model, then the fatigue life of fiber reinforcedasphalt concrete bridge deck pavement and ordinary asphalt concrete bridge deckpavement are analysised and calculated by using the solid model, the calculatedresults are compared finally.Finally, to demonstrate the practical significance of the study, the authorintroduces the construction technology and economic benefits of the polyacrylonitrile fiber asphalt concrete pavement according to the engineering example, The resultshows that the difficulty of the construction technology in a controlled range and highprice-ratio.