Evaluation of the Effect of Fibers on Mechanical Properties of Concrete Containing Reclaimed Asphalt Pavement

Research on the possibility of using Reclaimed Asphalt Pavement (RAP) as a part of pavement materials is increasingly carried out. Economic and environmental considerations are the most reasons in this regard.  In this process, the reclaimed asphalt pavement replaces some of the aggregates in the concrete or asphalt mixtures. Since the previous studies mainly showed the negative effect of reclaimed asphalt pavement on fracture and compressive strength of concrete and on the other hand some studies indicated the positive effect of fibers on the strength of cement concrete, in the present research study the effect of Polypropylene, Polyolefin and steel fibers on mechanical properties (compressive strength, tensile strength and fracture resistance) of concrete containing reclaimed asphalt pavement was evaluated. For this, three different percentages (2, 5 and 8% by weight of cement) of each type of fiber were added to the concrete containing 15, 30 and 45% reclaimed asphalt pavement, and compressive strength, tensile strength and fracture resistance tests were carried out. The specimens used in the fracture resistance test were semi-circular and had three notch depths of 25, 32 and 38 mm. investigation of the tests results indicated that the addition of the fibers to concrete containing RAP may lead to slight increase in compressive strength (up to 7%), small increase in tensile strength (up to 19%) and considerable effect on fracture resistance (up to 30%).