Effect of Compaction Methods on Physical and Mechanical Properties of Asphalt Mixture

Abstract

In this work, the reliability of the vertical vibration testing method (VVTM) is verified using laboratory and field tests. Then, the VVTM, Marshall compaction method (MCM), and modified Marshall compaction method (MMCM) are used to investigate the effects of different compaction methods on the physical and mechanical properties of asphalt mixtures. The results show that the VVTM has the least influence on the aggregate gradation of an asphalt mixture, and the specimens produced using VVTM have the best test accuracy when compared with the field cores. When the density of the asphalt mixture remains fixed, the average mechanical properties, e.g., Marshall stability, compressive strength, splitting strength, and shear strength, of the VVTM specimens are increased by at least 21% compared with those of the MCM specimens. Moreover, the mechanical properties of the mixtures increased by at least 13.2% when the mixture density increases by 1.8%. The results also show that the mechanical strength (Marshall stability, compressive strength, splitting strength, and shear strength) of the asphalt mixture is related to the mixture density and compaction method, whereas the optimal asphalt-aggregate ratio is only related to the mixture density. Moreover, the optimal asphalt-aggregate ratios of the VVTM and MMCM specimens are decreased by approximately 0.3% compared with those of the MCM specimens.