Effect of Oil Shale Ash on Static Creep Performance of Asphalt-Paving Mixtures

The objectives of the present study are to evaluate the effect of oil shale ash on the rutting of flexible pavement and to find the optimum percentages of ash, which will give the best properties of flexible pavement. Oil shale ash was used as an additive in an asphalt concrete mix. Specimens, with five-ash content (0%, 5%, 10%, 15% and 20%) by volume of binder, were made by Marshall Moulds. Then they we re exposed to creep tests (static) through the Universal Testing Machine (UTM). Three testing temperature levels (5oC, 25oC and 40oC) resembling relatively cold, moderate and high levels of temperature were considered. Oil shale ash is an air and water pollutant by product of oil shale rock. This research attempt to recycle oil shale ash by using it as an additive to hot mix asphalt (HMA). Furthermore, it will decrease the economic costs of constructing asphalt mix. The optimum percentage (12.5%) of oil shale ash addition it will increase the quality and performance of asphalt mix by reducing rutting. Statistical models analysis of the data provided by the UTM, consequently, this increased stiffness, resilient modulus and the accumulated strain of the asphalt concrete mix. Moreover, rutting depth and air voids were decreased.