Corrosion caused by seawater
Concrete has been used with excellent performance, in the environment and in contact with seawater for decades. However, special attention should be paid to the composition of the concrete needed for these severe conditions. Structures located in tidal areas, splashing and spraying of seawater, repetitive wetting and drying cycles and/or freezing and thawing are the most vulnerable. Sulfates and chlorides in seawater require the use of concrete with low capillary porosity and a suitable mineral composition of cement to minimize the corrosion of steel reinforcement and sulphate attack.
Sulfate-resistant cements or Portland cement with low value of tricalcium aluminate (3CaO·Al₂O₃) are recommended. A proper concrete cover should be provided over steel reinforcement as well.
The water cement ratio should not exceed 0,50. High-strength concrete is recommended in places where large ice formations are in contact with the concrete structure.
Environment: Impact of aerosols with no contact with seawater.
Example: Structures near to or on the seashore.
Additional classes covered: XC1, XC2, XC3, XF1, XD1, XD2, XA1
Environment: Permanently under water.
Example: Parts of maritime constructions.
Additional classes covered: XC1, XC2, XC3, XC4, XS1, XF1, XF2, XD1, XD2, XD3, XA1, XM1, XM2
Environment: Areas of tides, splashing and spraying of seawater.
Example: Parts of the maritime constructions.
Additional classes covered: XC1, XC2, XC3, XC4, XS1, XS2, XF1, XF2, XD1, XD2, XD3, XA1, XM1