Role of Carbon Nanomaterials as Reinforcing Phase in Improvement of Physico Chemical Properties of Pozzolana Portland Cement Morta

Abstract

iii newlineCement mortar is a common building material used all over the world and is the newlinefoundation of many civil engineering infrastructures. However, it is subject to a newlinenumber of constraints, some of which include low physico-mechanical strength, quasi newlinebrittleness, the cracking phenomena, high permeability, and porous microstructural newlinecharacteristics. Researchers in the past have used steel fibres, glass fibres, newlinepolypropylene fibres, carbon fibres, and other common materials as reinforcing newlineagents in the cement mortar to avoid these problems. But these materials only work to newlinestrengthen up to the micro-level, or marco-level, and cracks continue to form at the newlinenano-level in the cement mortar matrix. Nanotechnology has become an interesting newlineway to use nano-sized reinforcements in cement-based materials. Extraordinary newlinemechanical properties can be found in carbon nanomaterials (CNMs), such as onedimensional newlinefunctionalized multiwalled carbon nanotubes (FMWCNTs) and twodimensional newlinegraphene oxide (GO). CNMs, with their high surface area, high aspect newlineratio, and exceptional mechanical potential, add new dimensions at the interface to newlinethe cementitious matrix. Despite these benefits, there are several drawbacks to using newlineCNMs in the cementitious matrix. One of these is the difficulty of uniform distribution newlineof CNMs throughout the alkaline cement pore solution. newlineIn light of these observations, it is possible that CNMs can be covalently functionalized newlineand that CNMs can be dispersed by a superplasticizer to improve their dispersion. newlineAnother option is to incorporate hybrid CNMs (i.e., FMWCNTs and GO) as nanoreinforcements newlineinto the cementitious matrix to take advantage of their synergistic newlineimpact. Cement manufacturing seems to be a major contributor to the release of the newlinegreenhouse gas carbon dioxide. Using pozzolana portland cement has the potential to newlinereduce cement consumption and consequently cement-related CO2 emissions. The newlineresults of the thesis show that CNMs and hybrid CNMs play a role as reinforcing newlinephases in making pozzolana por