Durability of cementitious materials in seawater environment: a review on chemical interactions, hardened-state properties and environmental factors

Abstract

Global warming-induced sea level rise exacerbates the deterioration of maritime structures and imperils their long-term durability. Cementitious materials such as ordinary Portland cement (OPC), pozzolanic blended cement (PBC) and alkali-activated material (AAM) can chemically interact with seawater, leading to degradation of binding properties. Despite their extensive applications in construction industry, the seawater resistance of these materials remains elusive. The objective of this work is to review and compare the durability of OPC, PBC and AAM in seawater environment from the perspectives of chemical interactions and hardened-state properties. This paper first briefly explains the mechanism of seawater intrusion into hardened cementitious materials. The chemical interactions of chloride, sulphate and carbon dioxide from seawater with hydrate components in OPC, PBC and AAM are discussed. From the durability aspects, this study evaluates and compares the performance of cementitious materials, including compressive strength, mass change, porosity and water absorption, and chloride permeability. Seawater deterioration mechanisms coupled with environmental factors such as wetting–drying cycle, external loading and temperature are also presented. Based on the review, future research is suggested to improve the durability studies related to seawater attack. This review provides better insight into the development of sustainable seawater-resistant construction materials for applications in seawater environment.