Effect of oil palm empty fruit bunch ash (OPEFBA) on the compaction and some Index Properties of Sand-Bentonite Mixtures

Abstract

The effort to improve the shear strength and leakage-proof of sand-bentonite mixtures used in waste containment liners prompted the investigation of the effect of oil palm empty fruit bunch ash (OPEFBA), a pozzolanic material on the mixture. Index property tests were carried out on sand, bentonite and sand-bentonite mixtures. The sand belongs to the American Association of State Highway and Transportation Officials (AASHTO) group A-1. Bentonite was added to the sand in increments of 0, 10, 20, 30, 40, 50% by weight. Index property test results show that specific gravity decreased with increase in bentonite content while liquid limit, plastic limit, plasticity index and linear shrinkage increased with increase in bentonite content. Compaction test results show that Maximum Dry Unit Weight (MDUW) decreased with increase in bentonite content while Optimum Moisture Content (OMC) increased with increase in bentonite content. OPEFBA was incorporated in the mix at 2, 4, 6, 8 and 10% by weight. Graphical and statistical results obtained show that OPEFBA at the percentages used does not have significant effect on sand-bentonite mixtures. Since the initial trial was not successful, it is recommended that experimental design should be carried out for the other possible combinations and investigated further