| Summary: | This research focused the impact of various aggregate gradationson permanent deformation and moisture susceptibility of asphalt concrete mixtures. Fivewearing course of different gradation,namelyNHA-A, NHA-B, SP-1, SP-2 and MS-2,were adopted. Two pavinggradebitumeni.e. 40/50 and 60/70wereused. Hamburg Wheel Tracking Test (HWTT) and Modified Lottmantestwereperformed to assess rutting propensity and moisture damageof asphaltmixtures.The results indicatedthe superior performance ofNRL 40/50binderin HWTTwhile mixes prepared with Parco 60/70showed better resistance against moisture. In HWTT, NHA-A performed well followed by NHA-B and SP-2 while MS-2 and SP-1 failed the minimum rut depth criteria. All the mixtures passed the minimum benchmark for Tensile Strength Ratio (TSR). Aggregate gradation SP-1 given in Superpaveguidelinesprovided greater resistance to moisture damagedue to compact natureofthe blend. Rutting tendencyof the mixtures increased with increasing TSRand decreasing Indirect Tensile Strength (ITS).
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