Mechanical Properties of High-Calcium Fly Ash Geopolymer Mortar Incorporating Polypropylene Fiber

Abstract

This article examines the compressive strength and flexural strength of High-Calcium Fly Ash geopolymer mortar containing Palm Oil Fuel Ash (POFA) and Clay Residue (CR) as the starting materials. The polypropylene fiber (PF) was added in geopolymer mortar at the rates of0%, 0.25%, 0.50%, 0.75%, and
1.0% by volume fraction. The liquid alkaline was composed of 10 molar sodium hydroxide (NH) solution and sodium silicate (NS) solution with a constant NS-to-NH ratio of 1.0. A constant sand-to-binder ratio of 0.50 and waterproof-to-binder ratio of 5.0 were used in all mixtures. The test results showed that the incorporation of polypropylene fiber to geopolymer mortar improved its mechanical properties in comparison to mortar
without PF. In addition, geopolymer mortar containing PF could increase the toughness modulus and energy absorption prior to failure, therefore delaying the occurrence of failure.