Application of Automobile Used Engine Oils and Silica Fume to Improve Concrete Properties for Eco-Friendly Construction

Proper disposal of industrial waste can be very burdensome and expensive. On the other hand, improper disposal leads to environmental denigration. A brilliant, safe and cheap means of industrial waste disposal is its addition to concrete. These wastes are added to concrete to modify or improve the properties of the concrete in its fresh and/or hardened state. Used engine oil (UEO) and Silica fume (SF) are industrial wastes that can cause serious environmental pollution. A gallon of UEO is sufficient to pollute a million gallons of water. In this study, two types of UEOs (petrol and diesel engines) and SF are incorporated into concrete to improve the latter’s properties. The two UEOs are applied since they differ in chemical composition and undergo different operations. This study involves obtaining the optimum amounts of UEOs by considering workability and 28-day compressive strengths. Thereafter, SF of 10 % and 15 % replacement of cement was added to concrete with optimum UEOs and the properties were evaluated. The results showed that the UEOs and SF can be disposed of by adding to concrete to modify or improve properties. The results showed that the optimum DUEO and PUEO are 0.8 % and 0.6 % with 32 N/mm² and 31 N/mm² compressive strengths. The addition of the SF decreased workability by as much as 17.6 %, while having no significant influence on the compacting factor. In addition, the 10 % and 15 % of SF showed increase in the compressive strength of concrete with optimum UEOs by as much as 37 %.