Mechanical Response of a Sand, Reclaimed-Asphalt Pavement, and Portland Cement Mixture

This research was developed for the evaluation of the mechanical response of a mixture of soil and reclaimed-asphalt pavement (RAP) stabilized with cement. Mixtures were made containing 70% Osorio sand and 30% reclaimed-asphalt pavement (RAP), and portland cement. Tests of unconfined strength, pulse-velocity, durability, and simple shear were performed. The unconfined strength tests showed that the porosity/cement index controls the unconfined compressive, splitting tensile, and flexural tensile strength of the mixtures. The replacement of part of the Osorio sand by RAP did not present an expressive drop of strength in these tests. The pulse-velocity test presented that the initial shear modulus and the porosity/cement index, unconfined compressive strength, and tensile strength could be related. Wetting-drying durability tests displayed that the accumulated loss of mass increased when the cement content and the dry unit weight decreased. The monotonic shear response showed that the inclusion of RAP positively influenced the internal friction angle of the material and the cohesive intercept presented higher values for samples with lower porosity/cement index. The cyclic shear response presented that the shear modulus degradation was lower when the stress variation was lower. For higher variations, the degradation was greater.

Automated summary

This research aimed to evaluate the mechanical response of a mixture of soil and reclaimed-asphalt pavement (RAP) stabilized with cement. The tests showed that the porosity/cement index controls the strength of the mixtures and the inclusion of RAP positively influenced the internal friction angle of the material. The study also found that the accumulated loss of mass increased when the cement content and dry unit weight decreased.