Effect of used engine oil on structural behavior of reinforced concrete elements

摘要

This paper reports on the second phase of a research program started at the American University of Beirut (AUB) to study the effects of used engine oil on concrete properties and concrete behavior. In the first phase, the effect of used engine oil on properties of fresh and hardened concrete was investigated. Results indicated that used engine oil acted as an air-entraining agent by improving the slump and fluidity of the concrete mix, and enhancing the air content of fresh concrete. Reductions in the strength properties of hardened concrete due to the incorporation of oil were not as significant as when a commercial chemical air-entraining admixture was used. Results of the first phase of the AUB study instigated further investigation reported in this paper. The objective was to evaluate the effect of used engine oil on structural behavior of reinforced concrete elements. Six full-scale beam specimens were tested in three sets. The difference between the three sets was the mode of failure of the beams: flexure; shear; or bond. The two companion beams in each set were identical except for the use of engine oil in one of them. The beams were tested in positive bending. Results showed that regardless of the mode of failure, used engine oil did not have any significant effect on the ultimate load or load-deflection behavior of the beams.