Laboratory Performance of Liquid Anti-Stripping Agents in Asphalt Mixtures used in South Carolina

2018PDFTech ReportReport No. FHWA-SC-18-01SPR 726Antistrip additivesAsphalt mixturesHot mix paving mixturesStripping (Pavements)Liquid Anti-Stripping AgentsAsphaltPavementsSouth CarolinaSouth Carolina. Dept. of TransportationAmirkhanian, Serji N.Xiao, FeipengCorley, MaryTri-County Technical CollegeSouth Carolina. Dept. of TransportationUS Transportation CollectionStripping is a phenomenon involving the loss of adhesion or bond between the asphalt binder and the aggregate in an asphalt mixture. In general, stripping results from the presence of water combined with the adhesive relationship of the aggregate and the asphalt binder. Most State Highway Agencies (SHAs)require the use of an anti-strip additive to control moisture damage. Anti-strip additives could be divided into two broad categories: (a) hydrated lime Ca(OH)2 and (b) liquid anti-strip additives (ASAs). Although the SCDOT has been utilizing hydrated lime for many years in their hot mix asphalt (HMA)mixtures, there are many new liquid ASAs in the market that are proven to be effective in minimizing the moisture susceptibility of HMA mixtures. This research project investigates the effects of various liquid ASAs and hydrated lime on several high-traffic volume mixture types used in South Carolina. In addition, various dosage rates for the liquid ASAs included in this project are examined to determine recommended dosage rates