Abstract

With great concern about the environmental issues such as high energy demand and high CO2 emissions during the production of Portland cement (PC) and durability problems of PC-based concrete, there is an urgent need to find more sustainable solutions. The recently invented reactive MgO cements are claimed as a potential solution to deal with such environmental and durability issues. Basically, MgO cements are blends of reactive MgO and PC in different proportions depending on the application and intended benefits and were developed with a range of sustainability and technical benefits. With a small amount reactive MgO in PC, greater mechanical properties such as improved strength and density, and durability performance in terms of enhanced resistance to sulfate attack, acid attack are expected. However, there is very little data available regarding this novel reactive MgO cement system in general and its application in concrete in particular.

In this talk, citric acid reactivity of nine MgOs from different sources including commercial products and laboratory burned will be presented; workability, mechanical properties such as density, porosity and strength and durability performance in terms of resistance to HCl, sulfates and accelerated calcium leaching of PC concrete samples with 4-10% MgOs will be discussed.