Evaluation of Fly-Ash-Treated Reclaimed Asphalt Pavement for the Design of Sustainable Pavement Bases: An Indian Perspective

Abstract

Rising costs and scarcity of natural materials such as aggregates are forcing highway agencies to look for alternate pavement designs for new construction, maintenance, and rehabilitation. Several states in USA are currently allowing the use of reclaimed asphalt pavement (RAP) combined with cement for a stabilized base course under both asphalt and concrete pavements. India has very limited experience with recycling and reuse of RAP in various layers of pavement structure. The main objective of the present research is to evaluate the use of reclaimed aggregates from older pavements with addition of stabilizers to improve the pavement performance with long lasting and reduction of asphalt course, which in turn reduce the carbon footprint. RAP samples were collected from an ongoing project site, and the specimens are prepared with RAP as principal component. Fly ash is used as the stabilizer and the mixes are evaluated in the laboratory for its strength and stiffness along with resilient modulus studies. The fly ash stabilized RAP base layer significantly improved the resilient behavior at 30% fly ash replacement by weight. Further increase in fly ash content reduced the performance.

Wetting and Drying Characteristics of Recycled Asphalt Pavement-Fly Ash Blend as a Sustainable Pavement Material

“…An evaluation of FA-stabilized RAP as pavement base/sub-base material has been investigated by Saride et al, (2014) whom reported that the Unconfined Compression Strength (UCS) and resilient modulus (M R ) properties can be improved by FA replacement. However, the 7-day UCS of RAP was reported to be lower than the strength requirement specified for pavement base materials.…”