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Asphalt pavement with a short construction period, wear skid , vibration , low noise , ride comfort , no dust as well as simple maintenance and repair , and many other advantages , has been widely used in the high-grade highways . Asphalt pavement in cold seasons is easy to produce cracks , hot season is easy to produce , such as rutting and uplift . In order to improve the performance and life of the asphalt pavement , you must first figure out the mechanical properties of the asphalt road paving materials - asphalt mixture . Guide the thinking of the two-step method , the asphalt mixture as a two-phase composite material from tar sands and coarse aggregate . Tar sands as an isotropic material , the available viscoelastic mechanical model to describe the rheological behavior of the tar sands . Coarse aggregate suspension matrix of the tar sands , which change the overall indicator of the strength of the material and the rheological properties . , Speaking from a macro scale , the asphalt mixture can also approximate seen as an isotropic material , and the use of continuum theory to describe . Asphalt mixture is a multiphase composite material containing micro - pores , micro-cracks and other defects , it is necessary to apply damage mechanics theory to analyze the changes in the carrying capacity of the asphalt mixture . In fact , in the asphalt mixture creep process , the creep hardening and damage to the deterioration of the two mechanisms exist . The creep hardening cause deformation stabilize deterioration of injury lead to deformation acceleration , and eventually form a permanent deformation . In order to maintain the commonality between the different injury models with non-destructive creep model , the single scalar form of the Kachanov continuous damage to segmented form , then coupled injury - free creep constitutive model to form approximation creep damage constitutive model . On this basis , the ANSYS finite element software on asphalt mixture creep damage and rutting formation process simulation creep curve is consistent with the experimental results and the rut depth growth curve over time . Damage evolution model to explain the formation mechanism rutting .
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