Designing reinforced concrete structures in bridge, port, railway construction: solutions to improve the quality of the protective concrete cover

Abstract

This study presents an experimental investigation into the development of concrete suitable for structural components used in coastal environments. Due to the aggressive conditions in marine settings—such as high salinity, moisture, and temperature fluctuations—concrete durability is a critical concern. The research focuses on optimizing concrete mix designs by incorporating supplementary cementitious materials—specifically 10% fly ash and 30–40% ground granulated blast-furnace slag (GGBFS) to enhance the mechanical performance and durability of the concrete. A series of laboratory tests were conducted, including compressive strength, chloride ion penetration, to evaluate the behavior of the proposed concrete mixtures. The results indicate that certain combinations of supplementary cementitious materials (SCMs) and admixtures significantly improve resistance to chloride ingress and corrosion, making them suitable candidates for use in coastal structural components. These concrete mixtures achieved a minimum compressive strength of 30 MPa at 28 days and demonstrated excellent durability with charge passed values below 1000 Coulombs, indicating low chloride ion penetrability. These findings contribute to the development of more durable and sustainable concrete structures in marine environments.