Experimental Study on Plastic Shrinkage of M-sand Concrete

Due to faster dwindling of river sand, nowadays, the use of alternative aggregates such as manufactured sand (M-sand) is inevitable in concrete. Though the positivity of M-sand is reported in many literature, few literature report the drawback of angular shape and gradation of the M-sand in altering the properties of cement/concrete. Especially, the properties at fresh state are affected by the size, shape and volume of the fine and coarse aggregates. The properties at fresh state include plastic shrinkage, if unattended this will lead to durability issues. Most of the studies concentrate on strength parameters and influence of M-sand on properties such as plastic shrinkage is rarely addressed. In order to consider this important property, in the present study, the influence of M-sand on plastic shrinkage is investigated. The strength and plastic shrinkage properties of various mixes with M-sand and river sand are compared. It is found that the angular shape and coarser gradation of M-sand helps in reducing the plastic shrinkage compared to river sand. Further, it is found that when using M-sand as fine aggregate in the concrete, the composition of the fine and coarse aggregate is same that has positive effect on the plastic shrinkage. Hence, this study shows that M-sand can be considered as a successful alternative, not only in strength but also in controlling the plastic shrinkage.