Monitoring the Durability Issues of Asphalt Concrete Mixtures

Abstract

The asphalt concrete mixture is prone to environmental issues such as moisture damage and ageing. This may exhibit a great significance in the service performance of asphalt concrete pavement mixtures which may be more susceptible to many types of early distresses throughout its fatigue life. In the present investigation, asphalt concrete mixtures were prepared and compacted with the aid of laboratory roller compaction into a slab samples. optimum binder content was implemented. Extra samples were prepared at higher and lower binder content of 0.5 % (above and below the optimum). Asphalt concrete beam specimens were obtained from the prepared slab samples with the aid of a diamond saw. Part of the Asphalt concrete beam specimens were tested under four point’s repeated flexural stresses after practicing moisture damage while another part was subjected to long term ageing. The rate of change in the flexural strength was monitored and compared among the various testing conditions at 20 ºC environment and under constant micro-strain level of 750. It was observed that the lower flexural strength was observed for moisture damaged specimens while higher flexural strength could be detected for aged specimens as compared with the control mixtures. The binder content exhibits a significant influence on flexural strength of the asphalt concrete specimens since it declines significantly at higher or lower binder content as compared with that of specimens prepared at the optimum.