Hide/Show Apps

Incorporation of waste and pozzolanic materials as partial replacement for the development of sustainable concrete

Hamza, Ali
Excessive production of cement due to modern construction practices frames cement as a leading pollutant of releasing significant amounts of CO2 in the atmosphere. The thesis begins with the examination of the alternative binding materials used as partial replacement to cement. Supplementary cementitious material, silica fume, is used as partial replacement to Portland cement whereas, waste materials, marble dust and crushed bricks, are used as partial replacement to the fine aggregates in this thesis. The study investigates the long-term mechanical properties and durability characteristics of pozzolanic concrete incorporated with waste materials. The main parameters studied in this thesis are compressive strength, water permeability, resistance to sulfate and freeze and thaw attack as well as porosity. The development of the complex chemical reactions within the cement matrix such as cement hydration and pozzolanic reaction are examined using Scanning Electron Microscope. Material characterization is carried out using X-ray florescence and particle size distribution. The results suggested that it is not only possible to reduce the consumption of Portland cement and natural resources up to 40% using pozzolans and waste materials but also enhances the mechanical properties of concrete at long term. The use of waste materials in combination with pozzolans showed a dramatic decrease in water permeability and porosity as well as improved the resistance against external sulfate attack and action of freeze and thaw significantly.