Production of self-compacting concrete using Jordanian oil shale ash

Abstract

The potential of using Jordanian oil shale ash (OSA) as partial replacement of the cement on fresh and mechanical properties of self-compacting concrete (SCC) was investigated in depth. Six SCC mixtures were prepared with limestone filler and varying cement mass replacements of 0-30% OSA. The binder materials content was kept constant at (350 kg/m3) while the water-to-binder ratio was changed from 0.5 to 0.68 depending upon the amount of mixing water needed to achieve the required fresh properties. Standard cylinders (100x200 mm) were cast, then cured in water for 7, 28 and 56 days before being tested under compression to evaluate the mechanical properties of SCC. The strength of the SCC concrete decreased with higher OSA replacement contents although maintaining a higher value than that of conventional concrete made at almost the same cement factor. In general, replacement contents of cement by OSA not larger than 10% imparted limited negative impact on obtained mechanical properties. The SCC mixtures studied experienced high flowability, filling ability and resistance against segregation as indicated by the several tests carried out on fresh mixtures.