Using the indirect tensile fatigue test to evaluate fatigue characterisation of asphalt mixtures

Abstract

Fatigue cracking is a principal structural failure mode in asphalt pavement layers, resulting from repeated
traffic-induced loading stresses. Therefore, understanding fatigue deterioration behaviour is crucial for ensuring effective pavement design. In recent years, the indirect tensile fatigue test has become one of the most
commonly used methods for evaluating the fatigue behaviour of asphalt mixtures, owing to its simplicity and
suitability for cylindrical specimens either produced in the laboratory or cored from pavement construction
sites. In this research paper, the indirect tensile fatigue test was employed to assess the stiffness modulus and
fatigue behaviour of one unmodified asphalt mixture (DBM50) and two polymer-modified mixtures (EME2
and SMA) in stress-controlled mode across various temperatures. The results indicated that the indirect tensile fatigue test worked well and it can be considered to characterise effectively fatigue behaviour of different
asphalt mixtures in Vietnam. In addition, the test results revealed that the SMA mixtures exhibited the best
performance at both 20 °C and 10 °C compared to other mixtures. Specially, the fatigue lines for DBM50 and
SMA at 20 °C were positioned above those at 10 °C, while the fatigue lines for EME2 lines remained quite
similar across both temperature levels.