Avaliação em laboratório e em campo da deformação permanente de pavimentos asfálticos do Ceará e de São Paulo

Abstract

Rutting is a common distress in Brazilian asphalt pavements, reducing the driving comfort and safety, and in-creasing operational costs. This study aims to investigate a monitored test section (300 meters) of BR-222 in the state of Ceará, and another one of BR-116 in the state of São Paulo. It was observed the behavior of asphalt mixtures of these highways, in the laboratory by means of the uniaxial load repeated test and the Triaxial Stress Sweep (TSS), as well as in the field by making rutting measurements over time. The mixture in Ceará was designed by the Marshall method with an asphalt cement 50/70 from Petrobras/Lubnor. The mixture in São Paulo was designed by the Superpave methodology with an asphaltcement 30/45 from Petrobras/Replan. The results show that in the field, after only four months of opening to traffic, the mixture of Ceará presented wheel track rutting. In the laboratory, this mixture was also considered inappropriate by both rutting tests analyzed. The mixture of São Paulopresented until April 2015 (observation period), after 3.5 years in service, a good performance in the field, without observable rutting. In the laboratory, according to the uniaxial load repeat test thismixture presented a Flow Number (FN) compatible to heavy traffic. However, when considering the TSS test, this mixture fails to pass the reference test, making it impossible to preview the evolution of the investigated failure and suggesting sus-ceptibility to rutting, which is not in line with the results presented in the field up to this moment.