Effect of Incremental Compaction and Temperature on the Stiffness Parameters of Asphalt Concrete

This paper investigates the impact of elevated temperatures on the stiffness parameters of asphalt concrete and explores how incremental compaction can mitigate these effects. The Marshall method of mix design was adopted to prepare test samples. Incremental compaction was applied through the Marshall Impact Hammer (MIH), targeting 35, 50, 75, 95 and 115 blows while curing exposure ranged between 350C and 600C for 24 hours. The results reveal that exposure temperatures of up to 600C reduced strength and stiffness by 24.7% and 38.9% respectively, while increasing strains by 38.9%. However, with incremental compaction, tensile and compressive strengths increased 152% while strain reduced by 39.4%. Tensile and compressive elastic moduli increased by 45.5% and 45.8% respectively while dynamic modulus increased 8.8% despite elevated temperatures.