Using lateritic gravel as all-in aggregate for concrete production

Abstract

PurposeThe quest to reduce the cost of concrete which is a major construction input has prompted investigations into assessing the suitability of alternative sources of conventional materials. This paper aims to report the compressive strength and workability of lateritic gravel used as all-in aggregate for concrete production.Design/methodology/approachThree prescribed mixes from all-in aggregate concrete were compared with concrete from lateritic gravel. The paper investigated the variation in strength of four different mixes – 100: 0, 90: 10, 80: 20 and 70: 30 – when portions of the lateritic gravel were replaced with pit sand, respectively, using varying water cement ratios to achieve optimal workability.FindingsThe density and compressive strength of each cube was measured on the 7th and 28th test dates. An increase in slump and compressive strength was observed in the lateritic concrete, as portions of the lateritic gravel were replaced with sand. However, the rate of increase in the compressive strength tended to decrease with increase in part replacement of lateritic gravel with sand indicating that there was a threshold of percentage of sand increase after which the compressive strengths are likely to decrease. This work never reached this threshold, but it is estimated to be about 40 per cent.Research limitations/implicationsInvestigations focused on lateritic gravel sampled from two sites to represent samples from both the forest and savannah belt.Practical/implicationsLateritic gravel can be used as all-in aggregate for non-structural concrete.Originality/valueThe compressive strengths achieved were better than those for the available normal all-in aggregate used.