RCPT ASTM C 1202

RAPID CHLORIDE PENETRATION TEST In this test 95 mm dia and 50 mm thick disc is fixed between NaCl and NaOH solution. Then current is passed @ 60 volt for 6 hours and passed current measured in couloumbs its called chloride ion peremiablity. ( actually in this test electrical conductivity of concrete is measured, which gives a corelation to permiablity)

generally its limit is 1000 to 1500 coulombs at 28 days, but at 91 days its also permitted.

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