Durability of Fly Ash Geopolymer Concrete in a Seawater Environment

Abstract

This paper presents the results of a study on the durability of fly ash geopolymer concrete in a seawater environment. In this research, three different geopolymer mixes and a control mix were examined to determine the effective porosity, chloride ion penetration, and corrosion of steel reinforcement bars under open circuit potential and accelerated corrosion tests. High chloride ingress was observed on the geopolymer paste. A depassivation of the passive film of the steel reinforcement bar in fly ash geopolymer was faster than for the OPC concrete. Small corrosion activities were conversely evident in the geopolymer concrete under the accelerated corrosion test at an applied voltage of 30 V. Decreased corrosion rates were observed for the geopolymer concrete. The results obtained from these tests indicate that the nature of the geopolymer paste certainly influences its durability in the seawater environment.