Cements for marine environments

This paper presents the deterioration mechanisms of concrete structures within marine environments and it addresses the most appropriate cements for seawater constructions among the cements included in the European standard EN 197-1. The paper analyses separately sulphate and magnesium attack to concrete and chloride attack to reinforcing steel. The combined effect when both ions (sulphate and chloride ions) are present in the surrounding environment is also discussed. Once these deterioration mechanisms are described, it is shown how cement composition selection can help to extend the service life of concrete structures when exposed to marine environments. The benefits of supplementary cementitious materials (SCMs), such as fly ash, natural pozzolans and slag, among others, are also described. Reinforcement corrosion protection in marine environments is addressed according to the European concrete standard EN 206:2013 and the Spanish regulation on structural concrete, EHE-08, where two methods for evaluating the service life of a concrete structure are set: deemed to satisfy rules and modelling by performance. Finally, the paper gives some recommendations about the most appropriate cement types for marine environments and about concrete mix design.

Author: C. Bartolome, M.A. Sanjuan

Section: Concrete

Keywords: Seawater concrete, marine environment, sulphate resistant cement, calcium aluminates, concrete service life