Curing of concrete is an important topic that is specified in concrete standards such as NZS3101 and NZS3109:1997 which provide excellent guidance on what is required. There are still questions especially when considering alternative curing methods such as accelerated curing. Heating of concrete enhances the early-age strength of concrete but reduces long-term strength and durability. The overall effect is complicated since precast concrete manufacturers often use concrete of higher grade than specified to ensure good overnight strengths. Ultimately what needs to be assessed is whether the durability potential of the accelerated cured concrete is at least equivalent to the expected durability of the specified concrete after normal curing has been undertaken. This paper will summarise curing as outlined in NZS3101:2006 and NZS3109:1997. It will explain curing and why it is important not just to ensure strength but also for durability. Commentary will be made on the various types of curing and limitations that various methods may have as well as a discussion over accelerated curing. The results from a preliminary investigation on curing show that both the strength and permeability of heat treated specimens can be restored to the standard moist curing equivalent if subsequent curing is provided after accelerate heat treatment.
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