Permanent deformation and fatigue damage interaction in asphalt concrete using energy approach

Abstract

The interaction of fatigue and permanent deformation is very complex phenomenon and little attempt is made on this topic. This paper presents an investigation on the interaction of the two damages using the energy approach. Laboratory tests were conducted for both fatigue and permanent deformation on two different asphalt concrete in a sequential test procedure. A new failure criterion is proposed based on the dissipated energy ratio (DER). The proposed criterion for permanent deformation gives more damage indicator (inflection points) than the conventional flow number/strain rate criterion. The sequential test procedure is also found economical that can be standardized. From the study, strain hardening (pre-deformed) accelerates fatigue cracking susceptible. Similarly, high fatigued samples are more prone to permanent deformation than new samples. The energy approach is convenient for potential coupling of fatigue and permanent deformation interactions.