摘要 |
<p>An alkaline passive layer is maintained in contact with iron or steel reinforcement members in concrete structures by providing a CO2-barrier over substantially all air-contacting surfaces of the structure to prevent carbonation and loss of alkalinity, at least part of the barrier being water vapour-permeable and comprising an alkali metal carbonate and a carboxylic acid so that CO2 inflow is reduced or prevented whilst outflow of interstitial water vapour is allowed.</p> |