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The results for experimental determination of characteristics have been given and analyzed in this article for deformation and failure of an asphalt concrete at eleven loading rates from 0.000563 MPa/s to 0.652 MPa/s differing in 1158 times. A hot fine-grained dense asphalt concrete of type B prepared with a viscous bitumen of grade BND 100/130 which is traditionally used in road construction has been selected for the research. The tests have been performed at the temperature of 22–24 °C in a specially invented and assembled device according to the scheme of direct tension. The asphalt concrete samples had a shape of rectangular beam with dimensions 5×5×15 cm. It is found that from the moment of loading to the moment of failure the asphalt concrete is deformed nonlinearly. The rate of nonlinearity is increased with the load increase. Loading rate effects greatly the characteristics of deformation and failure of the asphalt concrete: failure time, specific work of deformation and failure deformation are decreased in 242, 160 and 3 times respectively at the loading rate increase in 1158 (nearly 1200) times from 0.000563 MPa/s to 0.652 MPa/s and the strength is increased in 5 times. Dependences for characteristics of the asphalt concrete failure (failure time, failure deformation, specific work of deformation and strength) on a loading rate are described with a high accuracy by power functions.

This work proposes an effective algorithm for description of nonlinear deformation of hereditary materials based on Rabotnov’s method of isochronous creep curves. The notions have been introduced for experimental and model rheological parameters and similarity coefficients of isochronous curves. It has been shown how using them, one can find instantaneous strains at various stress levels for description of nonlinear deformation of hereditary materials at creep. Relevant equations have been determined from the nonlinear integral equation of Yu. N. Rabotnov for the application cases of Rabotnov’s fractional exponential kernel and Abel’s kernel for nonlinear deformation of hereditary materials at creep. The improved methods have been given for determination of creep parameters α, ε0, δ, β, and λ. By processing and using test results for material Nylon 6 and glass-reinforced plastic ТС 8/3-250, the process has been shown for sequential implementation of the developed methods for description of linear and nonlinear deformation of these materials at creep. From the results of the experimental investigation performed by the authors of this paper, it has been determined that fine-grained, dense asphalt concrete at the temperature of 20 ± 2 °С and stresses up to 0.183 MPa at direct tension is deformed considerably in a nonlinear way. It has been shown in an illustrative way by construction of isochronous creep curves at various load durations and curves of experimental rheological parameter at various stresses. Nonlinear deformation of asphalt concrete at creep is adequately described by the proposed methods.