A comprehensive characterization of asphalt mixtures in compression.

摘要: Permanent deformation (i.e., rutting) is one of the major distresses in asphalt pavements, and it consists irrecoverable due to viscoplastic flow viscofracture fatigue damage. The mechanisms rutting have not been well addressed complexities mixture including (a) distinctions between compression, extension, tension; (b) rate temperature dependence; (c) dilative volumetric change; (d) frictional material with cohesion; (e) inherent anisotropy preferential aggregates’ orientation; (f) crack-induced crack growth; (g) strain hardening during accumulation; (h) softening evolution. In this project, all aforementioned fundamentals mixtures were simultaneously characterized by a comprehensive viscoplastic-fracture mechanistic model, which was incorporated modified effective stress consider cracking compression; smooth convex Generalized Drucker-Prager (GD-P) yield surface; non-associated rule; rate- temperature-dependent evolution that modeled an anisotropic damage density-based pseudo J-integral Paris’ law. model parameters related fundamental properties measurable understandable for civil engineers. A systemic testing protocol five individual test methods proposed determine properties. demonstrated be efficient, as could completely within 1 day. GD-P surface validated octahedral shear strength tests at different normal confining stresses. able characterize full range internal friction angles from 0 90 degrees. contrast, widely used Extended (ED-P) can only has angle less than 22 degrees convexity criterion surface.