Valoración experimental de soluciones para mejorar el índice de tolerancia al agrietamiento en mezclas asfálticas.

Abstract

One of the main problems that causes the deterioration of Ecuadorian flexible pavements are undoubtedly cracking of the asphalt layers, associated with the applied loads and the impact of climatic factors. However, the “Ministerio de Transporte y Obras Públicas” (MTOP) in its current technical specifications does not recommend or require the use of any basic test for routine cracking control. It is known that, in recent years, research in the US has proposed the use of the IDEAL Test that allows determining the crack tolerance index (CT index), already under the ASTM standard. Based on the above, the objective of this work is to assess the resistance to cracking using the IDEAL test on specimens aged in the short and long term, in a standard asphalt mixture to which three solutions will be used to improve that resistance: asphalts with polymers, asphalts with rejuvenators and fibers to the mixture, which will allow comparisons to be made and their possible behaviors to be evaluated. As a result, it is verified that, although the standard mixture meets very closely the requirement of CT index greater than 65, which is valid for dense mixtures aged in the short term and at 25ºC, the use of the rejuvenator shows great potential, reaching high average CT index values both in the short and long term, 80.9 and 68.0 respectively. The use of fibers didn’t have any effect and the use of polymers was negative, perhaps due to the mixing procedures.