Fatigue life evaluation of asphalt mixtures containing natural river sands and designed by bailey method

Abstract

Abstract. This study aims to investigate the efficiency of Bailey method of optimizing the fatigue life of asphalt mixtures when natural sand is included in the mix at two coarseness levels of aggregate gradations: Fine-Graded (FG) and Coarse-Graded (CG), with three mixes which varied with the percentage of the natural river sand, were prepared at each coarseness level, namely: Corse-Graded with Quarry Sand only (CG-QS), Corse-Graded with Natural Sands only (CG-NS), Corse-Graded with Quarry and Natural Sands (CG-QNS), Fine-Graded with Quarry Sand only (FG-QS), Fine-Graded with Natural Sands only (FG-NS), and Fine-Graded with Quarry and Natural Sands (CG-QNS). The portions of the natural sand either in CG-QNS and FG-QNS mixes were minimized as possible without violating the Bailey ratios. The Beam Fatigue (BF) test was used to evaluate the performance of each mixture at a strain level of 1000 micro strain. The sensitivities of the volumetric measures with Nf were evaluated. The study’s findings indicate that the Number of Cycles to Failure (Nf) was generally decreasing with the increase of the natural sand in the mix at any strain levels. The Dust Proportion (DP) was the most significant volumetric. The Bailey gradation method successfully provided a similar gradation coarseness for CG-QNS compared to CG-QS, which resulted in comparable Nf and indicates a similar aggregate interlock.