Effect of corncob, wheat straw, and plane leaf ashes as mineral admixtures on concrete durability

In this study, the effects of the use of corncob, wheat straw, and plane leaf ashes (CA, WSA, and PLA) as mineral admixtures on concrete durability were investigated. Ten concrete mixtures were produced in three series with control mixes having 400kg cement content. The control mixes were modified with 2, 4, and 6% of CA, WSA, and PLA in place of fine aggregate. To establish the durability of concrete, the compressive strengths were measured after 7, 28, 90, 180 days, and 18 months under sodium sulfate solution. In the meantime, abrasion resistance and water penetration were investigated. Test results indicate that CA, WSA, and PLA addition provides good workability and abrasion resistance compared to conventional concrete. Test results also showed that minimum abrasion resistance is obtained from the control specimen, while maximum abrasion resistance is obtained from CA3 (6%) specimens. Abrasion resistance is increased as the rate of fine CA, WSA, and PLA is increased. The results indicate that the increase in ash content caused a significant increase in the sodium sulfate resistance of the concretes. Hence, concrete with CA, WSA, and PLA addition can be recommended for the production of durable concrete. © 2008 ASCE