Abstract

As is known to all, compared with cement-based materials, geopolymer is an environmentally friendly cementitious material with low energy consumption and less emission of pollutants in the production process. Geopolymers were synthesized by French scientist Davidovits in 1978. Geopolymer is a kind of inorganic polymer material, which has high early strength, fast hardening rate and wide raw material source. Geopolymer is an active low calcium silicon-aluminum material mixed with alkaline activator, which is formed by curing later. Geopolymer is a new type of inorganic silica-aluminum cementite with a threedimensional network bonding structure similar to that of organic polymer. It has a threedimensional network structure composed of SiO4 and AlO4 tetrahedral units. The synthesis of geopolymers requires active solid silicoaluminate and alkaline solutions containing alkali metals and silicates. The alkaline solution plays the role of binder, alkali activator and dispersant. Under strong alkaline condition, geological minerals were excited by alkali silicate solution to form polyaluminum silicate materials. Today, terrestrial polymers are successfully produced from industrial wastes such as fly ash, volcanic ash and finely ground blast furnace slag. The acid and alkali resistance of geopolymer is obviously better than Portland cement. However, as a new material, geopolymer mortar has low flexural strength and tensile strength. Geopolymer has poor toughness and is very sensitive to microcracks. In order to improve the brittleness of geopolymer mortar, using fiber reinforced composite material is an effective and simple method. Through fiber reinforcement, the fiber in geopolymer can limit the growth of crack and enhance the ductility, toughness and tensile strength of geopolymer mortar.