Amirkabir University of Technology Amirkabir Journal of Civil Engineering 2588-297X 45 1 2013 08 23 Concrete containing rice husk ash to sulfate attack Concrete containing rice husk ash to sulfate attack 13 23 12 10.22060/ceej.2013.12 FA Ali Akbar Ramezan Pur Department of Civil Engineering, Concrete Technology and Durability Research Center, Amirkabir University of Poya Pur Beik Department of Civil Engineering, Amirkabir University of Technology, Tehran, Iran Faramarz Modi Concrete Technology and Durability Research Center, Amirkabir University of Technology, Tehran, Iran Journal Article 2014 03 14 Deterioration of concrete structures in sulfate environments is a well-known phenomenon. Cement chemistry is an important parameter in coping with sulfate attack. C3A and CA (OH)2 lead to expansion, cracking and strength reduction. The use of rice husk ash (RHA) can improve the sulfate resistance of concrete. It was observed that the sulfate resistance of blended cements was significantly higher in sulfate environments. This study investigates the effect of RHA replaced by cement on the durability of concrete due to sulfate attack. Three RHA replacement levels were considered in the study which is 7%, 10% and 15% by the weight of cement. After the specified initial moist curing period (28 days), concrete specimens were immersed in sodium sulfate & magnesium sulfate solution. The degree of sulfate attack was evaluated by measuring the compressive strength reduction of concrete cubes and their weight losses in both continuous immersed and wetting-drying conditions. Expansion observed in the ordinary Portland cement mortar prisms was larger than expansion for the RHA mortar prisms. Moreover, microstructure of the mortar and concrete incorporating Rice Husk Ash were studied through SEM tests. Deterioration of concrete structures in sulfate environments is a well-known phenomenon. Cement chemistry is an important parameter in coping with sulfate attack. C3A and CA (OH)2 lead to expansion, cracking and strength reduction. The use of rice husk ash (RHA) can improve the sulfate resistance of concrete. It was observed that the sulfate resistance of blended cements was significantly higher in sulfate environments. This study investigates the effect of RHA replaced by cement on the durability of concrete due to sulfate attack. Three RHA replacement levels were considered in the study which is 7%, 10% and 15% by the weight of cement. After the specified initial moist curing period (28 days), concrete specimens were immersed in sodium sulfate & magnesium sulfate solution. The degree of sulfate attack was evaluated by measuring the compressive strength reduction of concrete cubes and their weight losses in both continuous immersed and wetting-drying conditions. Expansion observed in the ordinary Portland cement mortar prisms was larger than expansion for the RHA mortar prisms. Moreover, microstructure of the mortar and concrete incorporating Rice Husk Ash were studied through SEM tests. https://ceej.aut.ac.ir/article_12_b956c06213b774bc5d570baba78a9b73.pdf