Climate change associated with carbon emissions is driving a demand for low-carbon cements. One of the most promising low-carbon alternatives is alkali-activated binder systems consisting of fly ash and ground granulated blast furnace slag. However, there are some issues related to their drying shrinkage which can be problematic when upscaling these binders to produce full size construction products. This study found that modifying the curing regime can reduce the drying shrinkage of alkali-activated mortars by up to 60%. The proportion of slag and fly ash employed also influences drying shrinkage behaviour but is less significant than the curing temperature and curing duration before drying is initiated. The drying shrinkage performance appears to be linked to the maturity and strength of the different mixes when drying begins.

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