Three-dimensional analysis of fatigue tests on bituminous mixtures

A tension-compression test on cylindrical specimens was used to study the three-dimensional behaviour of bituminous mixtures during fatigue tests. The tests were carried out at 10 degrees C, 10Hz at constant strain amplitude mode. The axial strain, radial strain and axial stress were measured using a prototype apparatus developed at the University of Lyon/Ecole Nationale des TPE (ENTPE). In addition to axial stress and strain analysis, the measurements of the radial strain made it possible to obtain the complex Poisson ratio and the volumetric strains during the tests. The results showed good correlations between the volumetric strains and global damage. The effects of the change of temperature due to viscous dissipation on the volumetric strain and on the complex modulus were also analysed.