In marine environment, the cover to reinforced concrete in exposure zones is specified to be much larger than normal concrete (e.g. 75mm). Based on past experimental studies, the concrete cover is identified to be directly related to the corrosion failure of marine structures.
In Eurocode 1 under Ultimate Limit State the probability of failure is less than 10-4 while under Serviceability Limit State the probability of failure is less than 10-2. For corrosion aspects, it is normally classified under SLS state. For OPC concrete with 50mm cover, the corrosion probability is found to be more than 10-2. However, with the use of 75mm cover, the corrosion probability is about 10-3, which fulfills the Eurocode requirement.
This question is taken from book named – A Closer Look at Prevailing Civil Engineering Practice – What, Why and How by Vincent T. H. CHU.
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