The effect of fine fraction of Reclaimed Asphalt Pavement (RAP) aggregates on durability characteristics of mortar and concrete were assessed. Furthermore, it increases the reusability of RAP in paving industry and encourages recycling in an environment-friendly manner. Though there was a reduction in strength properties, this study shows that RAP aggregates in AAC can be considered for non-structural applications. AAC with 75% RAP showed slump and unit weight of 155 mm and 2250 kg/m3, respectively, while 28 days compressive and split-tensile strength were 21 and 1.35 MPa, respectively. It was found that workability and density of fresh AAC decreased with inclusion of RAP aggregates. Fresh and hardened properties of developed AAC were experimentally determined. The replacement rates of 0, 25, 50 and 75% by weight for natural by RAP aggregates were studied. The raw materials used for the preparation of AAC were ground granulated blast furnace slag (GGBS), fly ash (FLA), sodium hydroxide (SH), sodium silicate (SS), natural and RAP aggregates. This paper investigates the effect of recycled asphalt pavement (RAP) aggregates on strength properties of fly ash/GGBS alkali-activated concrete (AAC).
This indicates that using a concrete containing RAP could possibly result in improvement in the performance of concrete pavements. Though the flexural strength of the concrete decreased as RAP was incorporated in the concrete, the resulting maximum stress to flexural strength ratio for the concrete was reduced as compared with that of a reference concrete with no RAP. When a finite element analysis was performed to determine the maximum stresses in typical concrete pavements in Florida under critical temperature and load conditions, the maximum stresses in the pavement were found to decrease as the RAP content of the concrete increased, due to a decrease in the elastic modulus of the concrete. The coefficient of thermal expansion and drying shrinkage did not appear to be significantly affected by RAP content. Results of the laboratory testing program indicate that compressive strength, splitting tensile strength, flexural strength, and elastic modulus of the concrete decreased as the percentage of RAP increased. Concrete containing 0, 10, 20, and 40% of RAP were produced in the laboratory and evaluated for their properties that are relevant to performance of concrete pavements. The feasibility of using concrete containing recycled asphalt pavement (RAP) in concrete pavement applications was evaluated.
0 kommentar(er)
