Influence of Stress Levels on the Development of Permanent Deformation in Unbound Granular Materials

This paper analyzes the permanent deformation performance of an unbound granular material that has been subjected to repeated triaxial loads. The unbound material tested was crushed granitic stone, frequently used as a sub-base for road pavements in the region of Galicia (Spain). The stress level was observed to have a significant effect on the development of permanent deformation in granular materials. This fact was taken into account to fit a model by means of multivariable non-linear regression analysis, according to the stress level and number of load cycles.