Investigation of bagasse ash as a substitute for sand in the construction

Abstract

Sugar industries in Uganda produce sugarcane bagasse ash (SBA) as a by-product after burning sugarcane bagasse to run the steam turbines for electricity production. However, the disposal of this ash is a challenge to the sugar industries and as such most of it is left unutilized and this has become an environmental hazard. On the other hand, the booming construction industry in Uganda has led to increased use sand whose mining endangers many wetland ecosystems. This research was conducted to investigate the potential of bagasse ash as a substitute for sand. Bagasse ash samples were collected from KSL and its characterization was done at Geology laboratory at Makerere University using XRF machine. Thirty-six concrete cubes of dimensions 150 mm were made, with different proportions of SBA namely; 0 %, 15 %, 30 %, 50 % and 70 % substitution of sand were cast in the cubes using a mix design M 30 in ratios of 1:1.5:3. Three replicates in each proportion were made; the cubes were cured and tested for compressive strength at test ages of 7, 14 and 28 days. The results showed that compressive strength of concrete was 27.69 MPa to 28.03 MPa when sand is substituted by SBA from 30 % to 50 % respectively at test age of 28 days. These findings therefore recommend 30 % to 50 % substitution of sand with SBA in concrete.