Properties of self-compacting concrete containing granite dust particles

In the course of production in the Granite Industry, a lot of quarry dust wastes is generated which is either heaped at sites causing environmental and health hazards or dumped in landfills causing ecological problems. It is imperative to evolve a viable option for disposal so to rid the environment of this menace. This study investigated the use of quarry dust particles (QDP) generated from the granite industry as a cement replacement in self-compacting concrete (SCC). The experimental program was carried out in two phases: the first phase optimized the amount of QDP as replacement of Portland cement (PC) with acceptable flow-ability. The second phase evaluated the fresh and hardened properties of SCC which include tests on slump flow, J-ring and L-box to determine filling, passing abilities of SCC while compression and splitting tensile tests were conducted to determine the compressive and splitting tensile strengths, respectively. Test results show that at 20% replacement of cement with QDP, the SCC-QDP mixes has a slump ranged from 642 to 730 mm compared with 578 mm for SCC mix, a compressive strength of 37 N/mm2 compared with 30 N/mm2 for SCC. This was enhanced by QDP which filled the voids between the coarse grains of cement and water molecules which facilitated the flow ability of the mixes and then at later ages reacted with liberated calcium hydroxide from cement hydration to enhance the strength of the mixes. The results then indicated that QDP can be used to replace PC up to 20% by mass of PC in the production of SCC without adverse effect on both fresh and hardened properties. This results also show that QDP, a suitable material for partial replacement of PC in SCC production, can be used to reduce demand for cement thus reducing carbon dioxide emission and also solve other environmental problems