P. Chindaprasirt, W. Chalee
Jul 30, 2014
Citations
3
Influential Citations
187
Citations
Quality indicators
Journal
Construction and Building Materials
Abstract
Abstract In this research, the effect of sodium hydroxide (Na(OH)) concentrations on chloride penetration, steel corrosion and compressive strength of fly ash-based geopolymer concretes under marine environment were studied. The geopolymer concrete were prepared from class C fly ash with sodium silicate (Na 2 SiO 3 ) and sodium hydroxide (Na(OH)) solutions. The concentrations of Na(OH) of 8, 10, 12, 14, 16 and 18 molar, and the constant molar ratio of SiO 2 /Al 2 O 3 were used. The 200 × 200 × 200 mm 3 concrete cube specimens with steel bar embedded at coverings of 20, 50 and 75 mm were investigated. The specimens were air-cured in laboratory for 28 days and then were exposed to tidal zone of marine environment in the Gulf of Thailand. After 3-year exposure, the specimens were tested for compressive strength, chloride penetration and corrosion of embedded steel bar. The results showed that the chloride penetration and corrosion of embedded steel decreased with the increasing of Na(OH) concentration. The steel corrosion was related to the compressive strength of geopolymer concrete. The corrosion is high with the concrete of low compressive strength. In addition, increasing the Na(OH) concentration in geopolymer concrete resulted in a decrease in the chloride binding capacity.