Effect of extrinsic and intrinsic parameters on fatigue performance of hot mix asphalt mixtures: a review

Fatigue is a common form of distress that occurs on road pavements and severely affects serviceability. This distress is primarily due to heavy transient loadings, adverse environmental conditions, poor construction quality, and design faults. To access the failure mechanism of fatigue distress numerous studies have been carried out considering temperature, loading characteristics, and material properties such as stiffness, shape indices, gradation of aggregate, etc. Globally, researchers have been trying to understand the potential cause of fatigue distress and made substantial contributions to minimize or mitigate the problem. Critical appraisal of solutions and recommendations made by various researchers is the aim of this paper. This study has been organized in terms of fundamental philosophy, experimental practices, diagnosing for fatigue distress, governing factors and predictive models of fatigue performance, and analysis tools for understanding fatigue behavior. An extensive literature review has been carried out to analyze and interpret extrinsic and intrinsic parameters in the defined directions. The results indicate a significant enhancement in the stiffness characteristics and fatigue life of the asphalt mixtures when modifying the conventional mixtures with various factors such as a modified binder, adjusted aggregate gradation, incorporation of reclaimed asphalt aggregates, and utilization of industrial by-products like steel slag. Further, few researchers have focused on understanding the sensitivity of extrinsic parameters such as temperature, vehicular loadings, and moisture susceptibility on conventional and modified asphalt mixtures. Thus, the aggregate and disaggregate fatigue behavior of conventional and modified asphalt mixtures upon considering extrinsic and intrinsic parameters were highlighted in this study.