Strain Response of Reclaimed Asphalt Pavement Material Blends under Extended Loading Testing

Abstract

The use of reclaimed asphalt pavement (RAP) material in new paving projects is increasing in popularity, with research showing that RAP blended with aggregate will increase the resilient modulus of subgrade material. These studies have focused on the effects of RAP on the resilient modulus of the base layer without in-depth observation into the factors affecting permanent deformation. The objective of this research is to examine the early and long-term development of cumulative strain in RAP blends under combinations of moisture content, content of fines, and stress levels. Single stage testing is conducted in the laboratory for sample materials containing aggregate and RAP material. Cumulative strain percentage is the quantity of comparison between materials and testing results. Blends of 50% RAP and 50% Class 5 mixed at optimum moisture content (OMC) yield the lowest strain rates in the early testing stages and the lowest long-term accumulated strain. Blends tested with 10% fines yield comparable results to all OMC blends. Blends with