Healing process in Mineral asphalt mixtures

Abstract

The article presents an issue related to the phenomenon of regeneration occurring in mineral-asphalt mixtures. The introduction of the work discusses the problem of decreasing strength and fatigue life of asphalt mixtures expressed by changing the stiffness modulus. Attention is paid to the complexity of this phenomenon, which is associated with microstructural changes. The review of the state of knowledge discusses a phenomenon called "healing" referring directly to the regeneration of mineral-asphalt mixtures. Later on, based on fatigue tests of the four-point bending beam in the controlled deformation mode, this phenomenon was analyzed. Rest periods between load and heating of samples regenerating the tested mixture are taken into account. Based on the analysis of the test results, it was found that the heating process is a more effective factor leading to a greater regeneration gain not only the stiffness of the sample, but also its lifespan expressed in cycles compared to the rest period. At the end of the work, hysteresis changes were shown to analyze energy changes and the essence of regenerative processes in the context of extending the life of mineral asphalt mixes used in the pavement construction layers.