Investigating Resilient Modulus Interdependence to Moisture for Reclaimed Asphalt Pavement Aggregates

A variety of factors affect the overall performance of the material within pavement structure, with moisture content susceptibility being recognized as one of the most important factors that is known to directly affect the resilient modulus of granular base layer materials and consequently the overall performance of pavement structures. While the effect has been widely investigated for virgin aggregate, more limited research has been undertaken to quantify the effect of various moisture conditions on base layer materials containing reclaimed asphalt pavement (RAP) material. The present study aims to examine the effect of moisture on the resilient modulus of base layer materials containing RAP and a direct comparison to a virgin aggregate is presented, in order to identify potential variations in performance. Specifically more in depth information is provided regarding the sensitivity of RAP to variations in moisture conditions. Resilient modulus determination was performed, via laboratory triaxial testing on materials with varying RAP percentages and moisture contents and compared to the behavior of a course grained virgin aggregate material under similar conditions. For the current research the investigated RAP material exhibited modulus values that are equivalent or exceed those of a virgin aggregate utilized for base material at OMC and below. More details outlining the variations in modulus under various loading conditions are presented.