Effect of functional grading on the performance of flexible pavements

Abstract

Fatigue failure is an important type of pavement distress which is considered in the pavement design. In this study, it is aimed to increase the fatigue strength of the pavement without using any additives. For this purpose, the functional grading concept and pavement life have been correlated. Functionally graded materials are defined as a new material with graded structural functions and find application in many areas such as aerospace, automobile, medicine, and energy. In functionally graded materials, the material property is changed gradually depending on a particular function, which removes the problems that occur in the composites due to the sudden change in material properties. In this study, the problem of functional grading of asphalt concrete and base layers is discussed. Pavement life of the graded cross-sections compared with conventional cross-sections depending on the parameters such as loading radius, loading pressure, wheel and axle configurations, and material definitions. The most remarkable finding in the study is that pavement life can be increased by 59% as a result of the grading of the asphalt concrete and base layers together.