Assessment of the Extended Fatigue Life for Rubber and Polymer Modified Asphalt Mixtures Using Flexural Bending Beam Fatigue Test

Load associated fatigue cracking is one of the major distress types occurring in flexible pavement systems. Flexural bending beam fatigue laboratory test has been used for several decades and is considered to be an integral part of the new superpave advanced characterization procedure. One of the most significant solutions to prolong the fatigue life for an asphaltic mixture is to utilize flexible materials as rubber or polymer fibers. A laboratory testing program was performed at Arizona State University (ASU) on a reference, Asphalt Rubber (AR) and polymer modified gap graded mixtures. Strain controlled fatigue tests were conducted according to American Association of State Highway and Transportation Officials (AASHTO) procedures. Using COANOVA statistical analysis approach, the results from the beam fatigue tests indicated that the AR and polymer modified gap graded mixtures would have much longer fatigue life compared with the reference (conventional) mixtures.