Mechanical Response Analysis Of Composite Base Asphalt Pavement Under Heterogeneous Load

Graded crushed stone is a kind of unbonded granular material with good drainage performance,thermal insulation performance and the performance of not transferring stress and strain of crack tip.As the upper base of semi-rigid pavement,it can suppress the reflection cracks caused by dry shrinkage and temperature shrinkage of semi-rigid base.Therefore,in this paper,ABAQUS simulation software is used to analyze the mechanical properties of composite asphalt pavement with more realistic rectangular heterogeneous distribution load.Firstly,based on the elastic-plastic theory,the influence of the thickness and modulus of graded crushed stone layer on the structural mechanical index of pavement under different axial loads is analyzed.The results show that the axial weight has the greatest influence on the pavement mechanics index,followed by the graded gravel layer thickness,and the modulus has less influence on the pavement mechanics index.Then,based on Coulomb’s law of friction,the influence of the contact state between graded gravel layers on the pavement structure under static load and semi-sinusoidal dynamic load is analyzed.The results show that the results of pavement mechanics indexes under static load and dynamic load are basically the same,the results of pavement mechanics indexes under completely smooth contact condition are larger,some continuous results are close to smooth state,and the results under completely continuous state are the smallest.Finally,based on the fracture theory,reflective cracks are set on semi-rigid base pavement and composite base pavement,and the variation of stress intensity factor under different axial loads is observed to analyze the propagation of reflected cracks.The results show that overloading and overloading can accelerate the growth of reflected cracks,and the graded gravel layer can inhibit the growth of reflected cracks.Figure[69]table[16]reference[52]...