STRENGTH OF CONCRETES CONTAINING HIGH MICROSILICA CONTENT

摘要

The influence of curing temperature and high microsilica content on compressive strength of concrete mixes was studied. Four concrete mixes were cast and cured at 20℃ and 50℃. 20% of the NPC was replaced by microsilica at different water-cementitous materials ratio (w/cm); i.e., 0.643, 0.706, and 0.50. Superplasticizer was added to some mixes to assist in maintaining a constant slump range. Concrete samples were cured at 20℃ and 50℃ by means of water tanks. The results indicated that, at 20?, microsilica resulted in lower strengths at early ages only. At later ages, strengths of microsilica concretes were found to be either similar or higher. At 50℃, microsilica resulted in similar or stronger samples than plain NPC throughout the age at both curing temperatures. A comparison of the results of each mix indicated that high curing temperatures adversely affect the compressive strength of concretes including those containing microsilica.