EVALUATION OF CONSTRUCTION MATERIAL RECYCLING FOR HOT MIX ASPHALT

Laboratory testing of permanent deformation, resilient modulus, and stripping was performed to evaluate the engineering properties of construction material recycling (CMR) for compacted dense-graded hot mix asphalt by an analysis of variance (ANOVA) and Duncan’s multiple range tests. Four different proportions of igneous crush stone (ICS) and CMR used for mixtures are: (a) 100% ICS, (b) 100% CMR, (c) 50% coarse and fine CMR plus 50% coarse and fine ICS (50% CMR + 50% ICS), and (d) coarse CMR plus fine ICS (C-CMR + F-ICS). Two types of asphalt cement AC-10 and AC-20 are used as a binder for mixtures. On the basis of this study, the ANOVA of permanent deformation test shows that the types of aggregate have a significantly effect, no matter what test temperatures and binders used. The ANOVA of resilient modulus test shows the types of binder and aggregate do not have a significantly effect at test temperatures of 25 °C, but a significantly effect the types of binder at 40 °C. The analysis results of Duncan's multiple range test on permanent deformation at 2520 cycles indicate that the optimum mix properties is the C-CMR + F-ICS mixtures. All of the four-type mixtures for stripping test are satisfied the Taiwan Transportation Agency’s requirements.