RCPT - rapid chloride ions penetration test

Rapid chloride ion penetration test as per ASTM C 1202 is test of concrete in which 95 mm - 102 mm diameter and 50 mm thick concrete disc is fixed between NaCl and NaOH solutions.
Then current is passed through it @60 volt for 6 hours, passed current is measured in couloumb.
This is called chloride ion permiablity.
Actually it's a permiablity test for concrete.
Generally it's limits is 1000 to 1500 coulomb at 28 days.
Test is also permitted on 56, 91 days.

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