Improving fly ash cementitious materials for sustainable construction through nanotechnology

This paper provides an overview to several studies conducted at the Center for Advanced Cement-Based Materials that demonstrate how fly ash and nanotechnology can be incorporated in cementitious materials to yield sustainable construction materials. Fly ash has been used in cement-based materials for several decades, and has garnered attention in recent years due to environmental concerns such as reducing cement CO ₂ emissions and fly ash landfill requirements. Aside from significant environmental benefits, if designed properly, concrete containing high volumes of fly ash can exhibit superior strength, durability and fresh-state properties such as flowability. However, problems such as variable material performance, unstable air-void systems and slow strength development have hindered wide use especially in the United States. The first study discussed involves the development of a nonclinker cement composed of cement kiln dust (another land-filled waste material) and class F fly ash.