摘要：Fly ash, which was once an environmental pollutant, has now found a good place in theconstruction industry, mainly in production of blended cement. Blended cement hasreplaced ordinary Portland cement (OPC) to a major extent, in lieu of its increaseddurability and lesser cost. In addition there is reduction in green house gases in themanufacturing of cement, thereby reducing pollution. The main aim of this work is tostudy the effect of sulphate attack in OPC and blended cement made by replacementof OPC with fly ash by 10%, 20% and 30%. When the analysis of concrete reveals ahigh sulphate content this does not necessarily indicate any deterioration althoughconversely, loss of strength or visible deterioration accompanied by high sulphate contentwould be evidence of sulphate attack. The properties were monitored periodically toexamine durability. Here, an attempt is made to know the effect of sulphate attack onblended cement by monitoring the properties like density variation, compressive strengthand water absorption. The test results discussed above conclude the effect of sulphateattack on OPC specimens and OPC specimens replaced with fly ash. The deteriorationstarts significantly after 60 days of curing in all cases. The concrete is good in sulphateresistant when fly ash is added. The fly ash added specimens performed better thanOPC specimens. The result of the study indicated that the replacement of cement with20% fly ash improved the durability of concrete to a larger extent. The final strengthreduction for the specimens attacked by magnesium sulphate solution were higherthan that those attacked by sodium sulphate solution.
