Fatigue Study in Asphalt Mixtures with RTR Using the Semi Circular Beam Test

Abstract

The hot asphalt mixes that make up the large number of paved routes in the Argentine Republic, present a combination of different materials, such as asphalt, whether conventional or modified, together with aggregates and filler. The most common problems in asphalt pavements are rutting, fatigue failure and thermal susceptibility, which are expected to become evident at the end of their useful life.

Fatigue pathology in flexible pavements is a problem that is not achieved by overcoming the last state of the material, but by the successive application of loads that progressively consume the internal energy of the material. One of the materials to improve fatigue performance in asphalt mixtures is recycled tire rubber. Incorporations of up to around 10% by weight of RTR over the weight of asphalt significantly improve the rutting properties in dense asphalt mixtures. In this work, the evaluation of asphalt mixtures is proposed with the incorporation of RTR in 15 and 18% compared to the base asphalt cement. The evaluation of different fatigue characterization indices is proposed through the Semi Circular Beam test. At the same time, different levels of conditioning are considered to consider the aging that acts on the asphalt mixture during its manufacturing, processing and life in service.