Avaliação das propriedades reológicas de ligante asfáltico modificado com óleo de linhaça.

Abstract

Warm asphalt mixtures are an important alternative for the paving development, presenting a lower cost option, less environmental impacts and similar performance as the hot mixtures. There are various types of substances which added to the asphalt binder provide an reduction of the mixing and compaction temperature, what characterizes a warm mixture. Between the main modifiers are the oilseeds, witch reduces the temperature in about to 20°C in field applications. In this way, this research aims to evaluate an modified asphalt binder with linseed oil in the contents of 1, 2, 3, 4, 5 and 6% of the asphalt weight using the Performance Grade (PG), MSCR and LAS tests in the dynamic shear rheometer (DSR). Analyzing the results, it is verified that the mixing temperature can be reduced in up to 15°C with the 6% linseed oil sample, however the binder loses in its performance grade, supported traffic level and lifespan. In the ideal modification content, 4% of linseed oil, a reduction of about 10,8°C in the mixing temperature happens and the maximum PG temperature, 58°C, decreases only one degree comparing to the pure binder, 64°C. In addition, this content of asphalt binder presents the second largest lifespan of the studied contents, being classified by the MSCR test as ideal for standard traffic. The linseed oil showed itself a good green alternative for the production of warm mixtures, generating economy with the energetic spendings and reducing the emissions of toxic smoke which are harmful to people and the environment.