Structural Analysis Of Thin Asphalt Pavement And Premature Pavement Distresses Prevention

Thin asphalt pavement structure is a combination of functionalperformance and structural performance. The surface layer and base and subbasework as a whole structure. It not only has advantages such as anti-slide, lownoise, good flatness features, but economical friendly because of the thinsurface layer. Thin asphalt pavement is widely used for the construction oflow-volume roads with excellent performance-price ratio. Present researches onthin asphalt pavement focus on the functional performance of thin layer, lack ofoverall characteristics as well as the design specifications and optimization ofthe structure.The proposed research develops a more systematic study includingstructural characteristics, mechanical properties and optimization of thin asphaltpavement structure by practical engineering research, theoretical analysis, finiteelement numerical simulation and model prediction.First, based on the actual project and MEPDG pavement design softwareplatform, the research calculates the engineering design and analyzes the criticalcontrol indicators of thin asphalt pavement. The research collects field surveyand premature pavement distresses relying on the project in Congo. Accordingto MEPDG software design, under actual traffic and environmental conditions,the research conducts the technical analysis of the engineering solution, theresult indicates insufficient strength and unclear design control indicators.Based on the detection results of the project and MEPDG design suggestions,the research proposes key design specifications to reduce premature distresseson thin asphalt pavement.Secondly, the research establishes a three-dimensional finite element modelof thin asphalt pavement structure with finite element software ANSYS platform.The design control index methods of thin asphalt pavement are calculatedby orthogonal parametric analysis. A part of full scale three-dimensional finiteelement model of thin asphalt pavement structure (10m lengh,7m width,6mdepth) is established, to simulate the stresses and strains and deformations of each structural layer under vehicle load. The tests use orthogonal design methodto conduct variable parameter analysis. The change and influence can affordsuggestions to calculation methods of design control indicators and structuralcombinations of thin asphalt pavement design.Finally, on the ground of finite element analysis, the research points out theimpact of key indicators on the fatigue life and recommends structuraloptimizations of thin asphalt pavement design as well as material tests toimprove functional performance. The fatigue life is determined by the indexvalues, and the proposed structural optimizations are based on theconclusions of fatigue life prediction. The material tests prove gilsonite hasexcellent performance of resistance to fatigue and temperature stability, and it issuitable for thin asphalt pavement.