Development of Sustainable Cementitious Materials

In this paper, two types of sustainable cementitious composites, geopolymer and magnesium phosphate cement, are introduced. The geopolymer is a type of amorphous alumino-silicate products and magnesium cement is MgO based cementitious material. Geopolymer can be synthesized by polycondensation reaction of geopolymeric precursor, and alkali polysilicates. The MgO cement can be obtained by properly mixing MgO particles, fly ash, and phosphate. Comparing to portland cement, geopolymers and magnesium phosphate cement are energy efficient and environment friendly. Thus they are sustainable cementitious materials. In the paper, the recent developments of these two materials at HKUST are presented. The investigation shows that these two materials have superior properties to the portland cement such as high early strength, excellent volume stability, better durability, good fire resistance, and easy manufacture process.