The Structural Behavior Analysis Of Inverted Base Of Asphalt Pavement

The stress-strain relationship of graded crushed rock shows obvious nonlinear characteristics, when applied between concrete-bound base and asphalt surface, thus formed the inverted pavement structure, the effect of the nonlinear characteristic on calculation precision of asphalt pavement structure based on the elastic multi-layer theory, is a important issue in Engineering.Firstly, in order to research the mechanical performance of graded crushed rock, two numerical models of static triaxial test for graded crushed rock are constructed by using PFC3D, based on the grading of granular transition layer, which is used for prevention and reflection crack, recommended by the specification. Calculations confirm a basic law for graded crushed rock samples, that the deviatoric stress’peak strength increases with the increase of confining pressure, then, compare and analyze the influence of different grading to resilient modulus.Secondly, resilient modulus of graded crushed rock reflects the change of stress, this article analyzes the resilient modulus and the first stress invariant under different confining pressure condition, and makes regressive analysis by k-θ model, thus attains the nonlinear resilient modulus of graded crushed rock.According to the nonlinear characteristic of graded crushed rock, use deflection and tensile stress on the bottom of asphalt layer as the control indicators, embeds the nonlinear resilient modulus of graded crushed rock in the elastic multi-layer model, analyzes the mechanics response of inverted pavement structure.Orthogonal analysis method is used to analyze the influence of different structural parameters on the deflection, tensile stress on the bottom of asphalt layer, tensile stress of semi-rigid base and vertical compressive strain of earth base, gives the influence order of these structural parameters on the indicators.Has paved the experimental road, obtains the grading of graded crushed rock through test, introduces the construction process of granular transition layer, such as gravel material mixing, transporting, paving and rolling, tests the compaction degree after rolling the experimental road, the results show that every layer’s compaction degree meets the specification for acceptable quality level.