BS EN 12390-12:2020 pdf download.Testing hardened concrete Part 12: Determination of the carbonation resistance of concrete一Accelerated carbonation method.
WARNING — Phcnolphthalcln Is listed in REACH appendIx 2 and Its lists of substances of very high concern. Phenolphthalein powder should be handled with the greatest care using safety gloves in a fume cupboard fitted with an extractor.
Where needed, a fixing solution to permanently fix the colour change in the concrete specimen, see Clause 7.
NOTE I Suppliers of some Indicator solutions also provide a fixing solution that permanently fixes the colour change.
A magnifier and a gauge with a precision of 0,5 mm.
A storage chamber with a carbon dioxide concentration within the storage chamber in percent by volume as indicated in Clause 4, temperature at (20 ± 2) °C and a relative humidity at (57 ± 3) %. see Annex A (informative) for details cia suitable chamber. The carbon dioxide concentration shall be within ±0.5 % by volume of the target value with no variation for longer than 4 Ii outside the target value i 1,0%.
NOTE 2 Experience 151 has shown that if saturated surface-dry specimens are placed in the storage chamber shortly after removal from water curing, the relative humidity can exceed that permitted. Also, without active control of the carbon dioxide concentration, the levels can drop below the permitted tolerance as the carbonation process continues. ThereFore, It is important that the storage chamber has active control on carbon dioxide concentration, relative humidity and temperature.
NOTE 3 Relative humidity levels can be maintained using methods at the discretion of the laboratory, For example active humidification/dehumidification.
NOTE 4 When the door of the storage chamber is openect the carbon dioxide concentration within the chamber can fall rapidly, and therefore, for practical reasons, a short period of low carbon dioxide concentration La acceptable. The cumulative periods of times or low carbon dioxide concentration cannot exceed 4% of the storage time of 63 days The rebtive carbon dioxide concentration Is expected to be within ± 0.1 % by volume of the target value during 96% of the storage time in the carbonation chamber.
Where needed, a fixing solution to permanently fix the colour change in the concrete specimen, see Clause 7.
NOTE I Suppliers of some Indicator solutions also provide a fixing solution that permanently fixes the colour change.
A magnifier and a gauge with a precision of 0,5 mm.
A storage chamber with a carbon dioxide concentration within the storage chamber in percent by volume as indicated in Clause 4, temperature at (20 ± 2) °C and a relative humidity at (57 ± 3) %. see Annex A (informative) for details cia suitable chamber. The carbon dioxide concentration shall be within ±0.5 % by volume of the target value with no variation for longer than 4 Ii outside the target value i 1,0%.
NOTE 2 Experience 151 has shown that if saturated surface-dry specimens are placed in the storage chamber shortly after removal from water curing, the relative humidity can exceed that permitted. Also, without active control of the carbon dioxide concentration, the levels can drop below the permitted tolerance as the carbonation process continues. ThereFore, It is important that the storage chamber has active control on carbon dioxide concentration, relative humidity and temperature.
NOTE 3 Relative humidity levels can be maintained using methods at the discretion of the laboratory, For example active humidification/dehumidification.
NOTE 4 When the door of the storage chamber is openect the carbon dioxide concentration within the chamber can fall rapidly, and therefore, for practical reasons, a short period of low carbon dioxide concentration La acceptable. The cumulative periods of times or low carbon dioxide concentration cannot exceed 4% of the storage time of 63 days The rebtive carbon dioxide concentration Is expected to be within ± 0.1 % by volume of the target value during 96% of the storage time in the carbonation chamber.
