Influence of manufactured sand's characteristics on its concrete performance

Manufactured sand (MS) is widely considered as an alternative of the river sand (RS) recently, and to clarify the influence significance and influence mechanism of MS characteristic parameters on its concrete performance is essential to its scientific application. This paper presented series of experimental studies on the influence of MS characteristics on MS concrete performance. Results indicated that the particle shape of MS had little influence on the performance of its concretes, while the stone powder of MS had more remarkable influence on its concrete performance. When the gradations of manufactured sand B (MSB) and RS was adjusted according to Fuller's curve, the strength of MSB concrete was only lower than that of RS concrete, thus the gradation of MS was not a negative characteristic to concrete strength. The stone powder of MS is most significant factor on its concrete strength and the strength can reach a peak value when the content of stone powder is 7.5%. The MSB concrete has narrower ITZ than that of RS, and only a small amount of AFt crystals is found in the ITZ of MSB, while the stick AFt, AFm and portlandite crystal are enriched at the ITZ of RS concrete, the microstructure of MSB concrete is denser than that of RS.