Influence of Glass Fibers on the Mechanical Properties and Impact Resistance of Slag Based Geopolymer Mortar

With excellent technical properties and a great reduction in carbon emissions (compared to Portland cement) and utilizing fly ash and slag (by-product), geopolymer is becoming increasingly popular. However, the brittle characteristics of geopolymer material are easy to damage under the impact (especially impacts from heavy objects and loads), making geopolymer material lose its ability to work. Therefore, this material must be reinforced by adding fibers to increase the impact resistance. This paper studied the influence of glass fiber on the workability, compressive and splitting tensile strengths, and impact resistance of geopolymer mortar. The binder blended between ground granulated blast-furnace slag (GGBFS) and fly ash was investigated. Glass fiber in range from 0.1 to 0.5% by volume was added in mixture. The results were shown that the high fiber dosage highly beneficial to the splitting tensile strength and impact energy of geopolymer mortar. However, the workability and compressive strength were reduced with an increasing in fiber content.