Performance and hydration characteristic of dark white evolution (DWE) cement composites blended with clay brick powder

Clay bricks powder (CB) behaviour on hydration characteristics of white cement pastes composites containing 5, 10, 20 and 25 mass % of CB (as substitution) was studied. Kinetic of hydration till 28 days was examined for all the ‎blends e.g: whiteness reflection (Ry), setting, free lime (FL) and ‎compressive mechanical ‎strength (CS) ‎‎ were all checked up. Scanning electron microscopy (SEM) techniques have been implemented to ‎investigate the behaviour, microstructure and features of CB-pastes composites. The substitution of 5.0wt. % CB has improved the compression mechanical strength, free lime content ‎ and microstructure features of white cement pastes composite. CB has a substantial impact on the performance of white cement composite pastes, reducing whiteness reflection (Ry), and setting times while enhancing mechanical strength, bulk density and gel to space ratio. The microscopic scanning showed the existence of a thicker and more finer microstructure from calcium silicate hydrate products leads to decrease in porosity of all white composites forming extra CSH (micro scale) tightening the skeleton matrix structure responsible for the enhancement of the mechanical strength and physical properties, as well as the original morphology of calcium mono-carboaluminate hydrate. It was strongly advised that the white cement composite include 95 percent + 5 percent CB has better performance than white ordinary cement, and it adequate optimal blend, it showed a high dense compact microstructure consisting mainly of microcrystalline fibrous group with a large proportion decrease the porosity of the blend. M-CB5 represent a new type of white cement can be used as dark white evolution (DWE) cement for various construction purposes and reduce the cost of WC with good chance of solid waste ‎recycling.