Estudio del envejecimiento de mezclas asfálticas con núcleos de obras y briquetas procesadas en laboratorio.

Abstract

This work´s objective is to analyze asphalt mixtures aging, through its stiffness modulus evaluation with the NAT equipment, using extracted cores from highways with different years from the coast of Ecuador and specimens with similar composition, elaborated in an asphalt plant and aged through accelerated aging tests. Taking as reference AASHTO R30 procedure, the loose mixture was short-term aged for 4 hours at 135°C and then long-term aged for the next periods: 0, 2.5, 5, 7.5 and 10 days at 85°C. These time periods were chosen to contrast the results of highway cores. All the fabricated mixtures, both the extracted from highways and the laboratory aged, were produced with the same granulometric requirements using crushed alluvial materials with the same type of national asphalt product. In addition, indirect tensile fatigue test was performed. The results indicated that within this range of aging periods, each day in the oven at 85°C is equivalent to 0.47 years. For this reason, it is considered that thermic aging by itself is not capable of adequately reproduce Ecuadorian coast highway aging. Although the UV radiation is a well-known parameter that has a lot of influence in our environment, it is not included in any procedures applied in our country. It is recommended to deepen in the study of aging for the development of standards that includes our asphalt and environment particularities.