SPR 703In this research project, asphalt binders containing various polymer modifiers were investigated throughexamining both binder and mixture properties.\ua0\ua0Two additional topics were also investigated, including: a) theeffects of liquid anti\u2010strip additives on asphalt mixtures; and b) the effects of natural sands in asphalt mixtures.\ua0\ua0The asphalt binder modifiers in this project included: two plastomers; an elastomer; PPA+SBS; terminallyblended ground tire rubber (GTR) binder; and a lab\u2010prepared GTR binder.\ua0\ua0The binder properties of 16 bindercombinations were obtained (e.g., viscosity, DSR, etc.) and compared.\ua0\ua0In addition, these modified binders wereused in mixtures with two aggregate sources, three anti\u2010strip additives, and varying RAP contents.\ua0\ua0There were32 different Superpave mix designs conducted for this project.\ua0\ua0Many engineering properties of the mixtureswere obtained, including: indirect tensile strength, tensile strength retained, rutting, and AMPT values.\ua0\ua0TheAMPT testing was conducted at different temperatures and frequencies.\ua0\ua0The results indicated that, in general,many of the alternate modified binders could be utilized in South Carolina hot mix asphalt (HMA) mixtures.\ua0\ua0Theresults also indicated that RAP and natural sand could be utilized, in limited quantities, in many mixtures usedon South Carolina secondary roads.\ua0\ua0In addition, the mixtures made with liquid anti\u2010strip additives in this projectin many cases produced moisture susceptibility values (e.g., ITS, TSR) that were compatible with those obtainedwith mixtures containing hydrated lime
