Avaliação do dano por umidade induzida e da recuperação de trincas em mástique

Abstract

Fatigue is one of the most common distresses found in asphalt mixes used in pavement surfaces layers. The analysis in the mastic has become an important alternative to access the behavior of mixtures. The Dynamic Mechanical Analyzer (DMA) is an important device to obtain some material properties such as: complex modulus and phase angle. DMA provides the possibility to follow the damage evolution with the increase in the number of cycles. It can also be used in the stress or strain controlled mode. In the present study the DMA was used to investigate the fatigue life of a mastic under three different conditions: (i) original; (ii) induced moisture; (iii) rest period, in order to access the susceptibility to moisture damage and also the healing potential (all the tests were performed in the strain controlled mode). The variation in the admissible number of load repetitions (N) was used to analyze the results. For the samples with induced moisture, the variation in the complex modulus was also analyzed. The results showed that under moisture conditions, the N value decreased approximately 50% and the complex modulus 80%. On the other hand, when rest periods were used, the N values increased more than 250%.