Evaluation of Compressive Strength Using Recycled Asphalt Pavement as Coarse Aggregate

Abstract

The compressive strength of concrete using coarse recycled asphalt pavement (coarse RAP) as coarse aggregate replacement at 5, 10, 15, 20, 25, 30, 35, 40, 45 and 50 percent by weight are investigated in this paper. The compressive strengths of concrete are designed according to ACI 211.1 standard for 25 MPa 32 MPa and 40 MPa at 28 days of curing. The compressive strengths of concrete using coarse recycled asphalt pavement as aggregate are compared with those of similar concretes using natural aggregate. From the test results, it is found that the compressive strength of concrete using coarse RAP is dependent on the coarse RAP replacement in the mix proportions. The test results also indicated that there is a systematic reduction in the compressive strengths with the increase in coarse RAP content. In addition, the concrete using coarse RAP as coarse aggregate with different replacement ratios is compared with those of similar concrete using natural aggregate in order to propose the compressive strength prediction equation for concrete using coarse RAP as aggregate. The mathematical equation of the relationship between normalized compressive strength versus coarse RAP replacement ratios is presented. Finally, the proposed equations in this paper are compared with previous research.