Maximizing Sustainability of Concrete through the Control of Moisture Rise and Drying Shrinkage Using Calcined Clay Pozzolan

The Ghanaian concrete industry is really a booming industry due to many infrastructural developments and the surge in residentialdevelopment. However, many developmental projects that utilize concrete do suffer from the negative impact of moisture riseincluding paint peeling-off, bacterial and fungi growth, and microcracks as well as unpleasant looks on buildings. Such negativeoutlook resulting from the effects of moisture rise affects the longevity of concrete and hence makes concrete less sustainable. Thisstudy seeks to develop materials that could minimize the rise of moisture or ions through concrete medium. The experimental worksperformed in this study included pozzolanic strength activity index, water sorptivity, and shrinkage test. Calcined clay producedfrom clay was used as pozzolan to replace Portland cement at 20%. The strength activity test showed that the cement containingthe calcined material attained higher strength activity indices than the control. The thermal gravimetric analysis showed that thepozzolan behaved partly as a filler material and partly as a pozzolanic material. The sorptivity results also showed that the blendedmix resulted in lower sorptivity values than the control mortar. The study recommends that calcined clay and Portland cementmixtures could be used to produce durable concrete to maximize sustainability.