Development of green concrete using geopolymer

Abstract

Portland cement is the main component of traditional concrete used for construction; hence it is widely used. The production of Portland cement produces a high amount of CO2 what makes it harmful for the environment. Therefore, geopolymer concrete has been of interest since it serves the same utilities as Portland cement concrete by using a different type of raw material. This material is coming from waste therefore do not cause environmental damage. This binder is created using materials rich in alumina and silica with addition of an activating solution known as the alkali solution. Fly ash coming from the burning of coal is used in this study along with an activating solution composed of sodium hydroxide and sodium silicate to produce an alternative binder for concrete. Fly-ash will be partially substituted by Glass Powder which is also a waste material to see its effect on geopolymer concrete. Moreover, the durability of geopolymer concrete will be checked and compared to that of ordinary Portland cement concrete in terms of acid attack and fire resistance. Therefore, mixtures with different percentages of glass powder (0%, 5%, 10% and 20%) were carried out and different molarities of NaOH (10M and 14M) to generate a geopolymer concrete that has workability, strength and durability properties. Compressive strength, acid attack, and fire resistance are the tests that are respectively done for the previously mentioned properties. Results showed that 5% glass powder replacement of fly-ash in geopolymer concrete with 14M as NaOH concentration gives a similar fc of 48.32 MPa compared to the reference GPC without glass that gives 47.73 MPa. Also, up to 10% substitution of fly-ash with glass powder do not have a major effect on the strength (45.8 MPa). In addition, geopolymer concrete gives better durability properties than ordinary Portland cement concrete.