Mix Design Performance Evaluation of Micro-surfacing with Reclaimed Asphalt Pavement (RAP)
摘要
In recent times, there has been a growing trend toward using reclaimed asphalt pavement (RAP), in asphalt mixtures to promote sustainability. In the present study, RAP has been used in micro-surfacing. Micro-surfacing is a pavement preservation technique used to extend the lifespan of roads and improve their surface characteristics. It involves the application of a thin layer of asphalt emulsion mixed with aggregate and additives to the existing road surface. This mixture is then spread over the road using specialized equipment. In India, micro-surfacing is increasingly being adopted as a cost-effective solution for maintaining and rehabilitating roads. This study utilized a single type of limestone aggregates for micro-surfacing, ensuring uniformity. Type III aggregate gradation using International Slurry Surfacing Association (ISSA) A-143 guidelines was utilized in this study. The asphalt emulsion, comprising 63% asphalt and 37% emulsifiers, water, polymer, and acid, underwent various tests alongside its residue. Recycled Asphalt Pavement (RAP) from a single source was analyzed and it contains 3.5% binder content. Mix designs adhered to ISSA A-143 guidelines, with two types of mixes created: one using 100% virgin aggregates (VAs) and another with 40% RAP and 60% VA. Comparing the results revealed a 3% decrease in optimum emulsion content for mixtures with 40% RAP. While incorporating RAP did not notably affect mixing time, samples containing RAP displayed lower cohesion values at 30 and 60 min, indicating a slower setting rate. Overall, the result shows that the RAP-containing mixtures met the permissible limits outlined in the ISSA A-143 guideline.