Experimental Evaluation of the Durability of Fly Ash-based Geopolymer Concrete in the Marine Environment

The construction industry is increasingly turning to the use of environmentally friendly materials in order to meet the sustainable aspect required by modern infrastructures. Consequently, for the last two decades, the expansion of this concept, and the increasing global warming have raised concerns on the extensive use of Portland cement due to the high amount of carbon dioxide gas associated with its production. The development of Geopolymer Concretes (GPC) offers promising signs for a change in the way of producing concrete. However, to seriously consider geopolymer binders as an alternative to ordinary Portland cement, the durability of this new material should be evaluated in any comparative analysis. The main purpose of this study was to evaluate the durability characteristics of low calcium fly ash-based geopolymer concretes subjected to the marine environment, compared to ordinary Portland cement concrete with similar exposure. To achieve this goal, 8 Molar Geopolymer, 14 Molar Geopolymer and Ordinary Portland Cement Concrete (OPC) mixes were prepared and tested for exposure in seawater. The test results indicate that the GPC shows excellent resistance to chloride attack, with longer time to corrosion cracking, compared to ordinary Portland cement concrete.