Application of gray relational analysis to evaluate HMA with reclaimed building materials

This study evaluates reclaimed building materials (RBM), including waste concrete, brick, and the, used as aggregate for hot mix asphalt (HMA). The analysis method of gray relational analysis (GRA) is presented to determine the best performance of the varying proportions of RBM with igneous crush stone (ICS) on HMA mixtures. Four types of aggregates are used for the mixtures: (a) 100% ICS; (b) 100% RBM; (c) 50% coarse and fine RBM plus 50% coarse and fine ICS (50% RBM plus 50% ICS); and (d) coarse RBM plus fine ICS (C-RBM plus F-ICS). Two types of asphalt cement, AC-10 and AC-20, are used as a binder for the mixtures. Laboratory tests of permanent deformation, resilient modulus, and stripping were evaluated by analysis of variance (ANOVA) and GRA. On the basis of this study, the ANOVA of the permanent deformation test shows that the type of aggregate has a significant effect, no matter what test temperatures and binders are used. The ANOVA of the resilient modulus test shows that the types of binder and aggregate do not significantly affect at test temperatures of 25 degrees C, but significantly affect the types of binder at 40 degrees C. The GRA result indicates that the best performance is the C-RBM plus F-ICS mixtures. For the stripping test, all 4 mixture types satisfied the Agency's requirements.