Investigating the effect of olive husk ash on the properties of asphalt concrete mixture

Technology in transportation used available resources to make it safe, fast, suitable, easy, economic, and environmental to transport people and goods. Olive Husk became an environmental problem as waste materials especially in the Middle East where huge quantities are found. The objective of this research is to investigate the effect of addition of Olive Husk Ash (OHA) on the properties of asphalt concrete mixtures. Marshall Test was used to perform the asphalt concrete mixture by the addition of OHA to the binder of asphalt; different percentages of OHA (0, 5, 10, 15, and 20%) by volume were added to the binder. Five percent of asphalt cements (5, 5.5, 6, 6.5 and 7%) by weight and limestone aggregate were used for preparing asphalt mixture specimens to find the optimum content of asphalt that could be used in the binder. Tests on flow, stability, air void percentage and void in mineral aggregate, retained stability, stiffness, and retained stiffness were made. The principle results on OHA as filler in Asphalt binder improves the Marshall Stability, and void in mineral aggregate and decrease in flow, retained stability, stiffness, and retained stiffness with a 10%-15% of olive husk ash replacement of asphalt binder. The contribution that OHA could be used as a pavement construction material in field.