Effect of steam curing cycles on strength and durability of SCC: A case study in precast concrete

In this study the effects of thirty-six different steam-curing regimes on the compressive strength and permeability of a self-compacting concrete mixture, used in precast concrete elements of Sadr elevated highway was investigated. Compressive strength measurements indicated that in a constant total time, increase in precuring period leads to lower immediate compressive strength. On the other hand, increase in treatment temperature and total cycle time (which means higher energy and time consumption) led to higher immediate compressive strength. Furthermore, durability tests results demonstrated that application of cycles with maximum temperature of 70 °C imposes negative effect on durability properties of reference SCC, such as surface resistivity and capillary absorption. Finally, on the basis of three criteria (compressive strength, permeability and energy consumption by steam curing cycle), an optimum steam curing cycle was introduced and utilized in the precast concrete plant.