Effects of Sulphates on Elastic Modulus of Concrete Samples Made from Blends of Cement with Oil Shale Ash
نویسندگان
چکیده
Concrete is a material both weak and strong. Its durability decreases under negative impact of several chemicals. In particular, when some sulphates in sea and ground waters react with cement paste, concrete expands and cracks; therefore, concrete has a very short life span. In that case, either the effects of sulphates should be suppressed as much as possible, or the performance of concrete should be increased. To increase the performance of concrete, some studies are in progress by adding some mineral additives to cement paste in predetermined ratios. In this study, the changes in moduli of static elasticity of the concrete (mortar) samples, produced by using Portland cement which contains 0, 15 and 30% oil shale ash by mass, and cured in Na2SO4 and MgSO4 solutions, were examined. Concrete containing 15% ash in cement gave optimum results.
منابع مشابه
The Effect of Sulphate on Length Change of Concrete
Sulphates usually affect calcium aluminates in cements. Sulphate ions might have negative effects on cement hydration and it would be a reason of decrease in cement strength. In this study, the effects of Na2SO4 solution on the concretes made from OPC with oil shale ash (OSA) addition (0, 15 and 30%) were investigated. Concretes with 15% OSA gave the lowest value of Length Change Factor (LCF). ...
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