Repercussion of reclaimed concrete fine aggregates over hot mix asphalt design

Abstract

The paper assesses the effect of replacement of the fine portion of natural fine aggregates (NFA) with reclaimed fine aggregates (RFA) on hot mix asphalt (HMA) design parameters by using the full factorial design method. For this, the RFA percentage and bitumen content (BC) percentage are considered as the factors in the design of experiments. The HMA samples with varying percentages of RFA as a fractional replacement of NFA along with varying percentages of BC have been prepared. The test results are analyzed using analysis of variance (ANOVA), and the outcomes depict the significant influences of the factors chosen on the different HMA volumetric parameters and Marshall design parameters. Further, the study indicated that both the chosen factors and their interaction have a significant effect on the properties of HMA like bulk density, air void, void filled with bitumen, and void mineral aggregate value. In addition to above, the fatigue resistance and moisture susceptibility of HMA mixes rise up to a certain RFA% replacement which encourages the substitution of RFA up to certain percentage in HMA mixes for constructions of the flexible pavements.