CORROSIVE WATERS: EVALUATING THE INFLUENCE OF SEAWATER ON CONCRETE DURABILITY

Abstract

Concrete is a widely utilized construction material known for its exceptional compressive strength, durability, and cost-effectiveness. However, the quality of concrete heavily relies on the treatment it undergoes during manufacturing to achieve high compressive strength, water-tightness, resistance to wear, and dimensional stability. A critical challenge in the construction industry emerges when concrete structures are employed in coastal areas, exposing them to seawater containing compounds that degrade concrete's durability. Seawater's detrimental impact on concrete arises due to the continuous interaction during the treatment process, leading to chemical reactions that weaken the material, resulting in fragility and eventual breakdown. Consequently, the obtained durability often falls significantly below the predicted values.

In recent years, researchers have shown increasing interest in exploring the influence of seawater curing on concrete's strength and durability. Previous studies highlight the significant impact of seawater curing on concrete's compressive strength and durability (Neville, 2011). The use of seawater can lead to corrosion of reinforcement bars and degradation of concrete structures over time, diminishing their overall lifespan (Broomfield, 2007).

Coastal construction projects utilizing concrete unavoidably encounter seawater, housing compounds that reduce concrete durability. The high salt content in seawater, particularly chloride (Cl), poses a threat to concrete and seeps into the material through capillary action, filling voids. As a result, the chemical compounds in seawater progressively corrode the concrete, leaving it brittle and damaged. This discrepancy between predicted and achieved durability arises as aggressive seawater compounds interact with concrete constituents, causing mass loss, strength and stiffness reduction, and accelerated weathering (Mehta, 1991).

Concrete properties are categorized into fresh concrete and hardened concrete, each holding specific quality criteria. Proper fresh concrete should be easily mixed, transported, poured, and compacted, without segregation or bleeding tendencies that compromise its quality. Good hardened concrete exhibits high compressive and tensile strength, exceptional resistance to water, air, and sulfate, low shrinkage, and long-term durability. Compressive strength is a critical indicator of structural quality, with higher strength correlating to superior concrete.

This study aims to comprehensively investigate the impact of seawater curing on concrete's compressive strength by comparing the strength of seawater-cured concrete to that cured in fresh water. The findings will provide valuable insights into seawater curing's effects on concrete strength and durability, informing the design and construction of structures in coastal areas where seawater exposure is unavoidable.