Sustainable approach for recycling treated oil sand waste in concrete: Engineering properties and potential applications

The environmental and ecological impacts associated with concrete industry represent a major sustainability challenge. However, employing materials that would otherwise be considered waste in designing concrete mixtures can increase its sustainability along with reducing harmful impact of waste disposal. Therefore, this study attempts to increase concrete sustainable benefits through reusing treated oil sand waste (TOSW) as a replacement for natural sand. Concrete mixture for continuous flight auger (CFA) piles was selected in order to examine the practicality of the proposed technique. Fresh and hardened properties along with durability performance of CFA concrete mixtures incorporating 10%, 20%, 30% and 40% TOSW as partial replacement of sand were investigated. Results show that the incorporation of TOSW, up to 30%, did not adversely affect the performance of CFA concrete mixtures. Moreover, the leaching of heavy metals from tested concrete was very low leading to a less harmful environment impact. Reusing of TOSW as partial replacement for sand in concrete mixtures for CFA piles is potentially feasible with environmental ecological and economic benefits.