Suitability of Laterite Fines as a Partial Replacement for Sand in the Production of Sandcrete Bricks
The provision of affordable housing units from indigenous building materials has been the focus of most researchers in recent times. This paper focuses on the utilisation of laterite fines as replacement for sand in the production of sandcrete bricks as masonry units. With a mix ratio and a water/cement ratio of 1:6 and 0.50 respectively, batches with 0% (control specimens), 10%, 20%, 30%, 40% and 50% laterite fines replacing the sand were adopted in this study. In all, 96 bricks were cast, tested and compared with those of conventional sandcrete bricks (control specimens). Tests studied were density, compressive strengths (wet and dry) and water absorption. Data results revealed that the laterite fines used could satisfactorily replace the sand up to 30% for the production of structural masonry units even though bricks need to be protected when used in waterlogged areas or below ground level.
EFFECTS OF VARYING CURING AGE AND WATER/CEMENT RATIO ON THE ELASTIC PROPERTIES OF LATERIZED CONCRETE
This paper reports the results of investigations carried out on the effect of varying curing age and water/cement ratio on the modulus of elasticity and modulus of deformability of laterized concrete. The test specimens were made with sieved samples of selected grain size ranges of laterite used as fine aggregates to replace sand in normal concrete. Batching was by weight. Three mix ratios of (1:1Â½:3), (1:2:4) and (1:3:6) were used. Water/cement ratio of 0.5, 0.6, 0.7 and 0.75 were used for each of the mix ratios. The specimens were tested at curing ages of seven to 28 days. The results showed that there was a corresponding increase in both modulus of elasticity and modulus of deformability of laterized concrete due to increase in curing ages. The mix proportion, compressive strength and water/cement ratio were found to have significant effects on both modulus of elasticity and modulus of deformability of laterized concrete.
Effect of replacement of lateritic soils with granite fines on the compressive and tensile strengths of laterized concrete
Abstract Over the years, research works have been carried out on lateritic soils with a view to investigating their usefulness wholly as a construction material or partly as a substitute for fine aggregate component of concrete. This paper presents the results of investigations carried out on how lateritic soils replaced with varying percentages of granite fines affect the compressive and tensile strengths of laterized concrete. Laterized concrete is concrete in which the fine aggregates is lateritic soil. The results showed that for different mix proportions (1:1:2, 1:1.5:3, 1:2:4 and 1:3:6) maximum compressive strength values were obtained for laterized concrete containing 50% granite fines. Also the addition of granite fines in laterized concrete resulted in a decrease in tensile strength. However, the tensile strengths obtained fall within the range of values (1.44– 2.0 N/mm 2 ) given for grade 30 concrete. Therefore, laterized concrete containing granite fines can be used in the construction of buildings and rural infrastructures.