IMPACT OF HYDRATED LIME AND SBS ON HMA MOISTURE SUSCEPTIBILITY

Haider F. Abbas alabady; Prof. Dr. Alaa Hussein Abed

doi:10.37591/jopc.v11i2.6917

Abstract

Abstract In recent years, many of the newly built asphalt and concrete roads in Baghdad and other Iraqi cities have broken down too soon. This has hurt the country's economy and public safety. One of the main reasons why these newly built roads break down is because of water damage. Leaking water weakens the bond between the aggregate and the asphalt, which makes it more likely that sidewalks will fall apart early. The main goal of this study is to figure out how sensitive anti-stripping materials are to moisture when they are mixed with hot concrete. SBS polymer was employed at a concentration of 4 % by weight of asphalt, and hydrated lime was added at concentrations of 1, 1.5, 2, and 3 % by weight of aggregate to replace part of the limestone dust filler. To reach the goal of this research, the Marshall Apparatus was used to find the best asphalt content, and Indirect Tensile Strength (ITS) and Tensile Strength Ratio were used to measure the performance of moisture damage (TSR). The results of the tests conducted for this research showed that the addition of 1.5% H.L to the control mixture led to a significant increase in the stability of Marshall and air voids, with an increase of (20.4% and 7%), respectively, with an increase in the optimum asphalt content. Moreover, the increase in the tensile strength ratio (TSR) was at the same rate and amounted to 13.6% when compared to the control mixture.While the addition of 4% SBS polymer led to an increase in Marshall Values and TSR values by (48% and 15%), respectively. Keywords: Moisture damage; Hot Mix Asphalt; Anti-stripping; Styrene–Butadiene–Styrene; Hydrated lime.