Fatigue Analysis of Coir Powder Modified Bitumen Using Linear Amplitude Sweep Test

The fatigue resistance of the asphalt binders is significant in the fatigue performance of asphalt pavements. Previously, the Super-pave specification parameter |G*|sinδ was identified and used for rating the asphalt binders based on their fatigue resistance. However, in ensuing research works, it was found that this parameter does not relate well with the accumulation of fatigue damages under strain-controlled conditions and significant efforts had been carried out to accurately measure and characterize the fatigue resistance of binders in a way that had been suitable for inclusion in binder specifications. This led to the suggestion of a new binder fatigue test using the linear amplitude sweep test in the DSR (dynamic shear rheometer) to find out the number of cycles to fatigue failure (Nf) and the effectiveness of this parameter to consider as the criterion for rating the binders based on their fatigue resistance.