Investigation in to the use of calcium carbide waste as a partial replacement of cement in sandcrete block

Abstract

ABSTRACT Portland cement production is gradually having an effect on global warming and on the continuous decline of limestone deposits. In order to mitigate the harmful effects of cement processing and recycling of calcium carbide waste, the properties of Calcium Carbide Waste (CCW) replacement of Ordinary Portland Cement (OPC) in sandcrete blocks have been studied. OPC was replaced by CCW at 10, 20,30,40,50 and 90 percent. Mixed ratio 1:6 and a water cement ratio of 0.4 were used. 195 blocks, measuring 100 mm× 100mm × 135 mm, were prepared and tested for compressive strength, tensile strength, water absorption and density after 7, 14, 28 and 56 days of curing. Results of sandcrete block compressive strength, apart from 90% replacement of CCW, the replacement of 10%, 20%, 30%,40% and 50% at age 21 were above the minimum compressive strength of 2.8 N/mm2 recommended by the Ghana Standard Authority (GS297, 2003). The density of the blocks decreased as the CCW content of the mixture increased. At day 21 average density decreased from 2107.619 kg/m3, 2083.095 kg/m3, 2035.238 kg/m3, 2030.476 kg/m3, 2005.952 kg/m3, 1982. 857 kg/m3 and1851.190 kg/m3 at a placement of CCW at 0%,10%, 20%, 30%, 40%, 50% and 90% respectively. The split tensile strength also decreased as the percentage of CCW increased. At 0.263N/mm2 strength on day 7, there is an increase difference of 0.009 N/mm2 strength on day 14 and a decrease at 0.19, 0.005 N/mm2 and 0.023 N/mm2 strength on days 21, 28, and 56, respectively. The absorption value increases gradually with the percentage rise in the CCW content However, the best results were obtained at 10% to 40% replacement of the 28-days curing, which met the standard requirementThe study, concluded that the calcium carbide waste is viable as partial replacement of cement in bricks as it gives the satisfactory results at 14 to 28 days of curing