Current concrete mix design standards are largely of the prescriptive type, i.e. recipe-based specifications that prescribe limiting values for certain mix design parameters, such as minimum cement content and maximum water/binder ratio. This has numerous economical, techni- cal and environmental disadvantages and is one of the driving factors behind the development of performance-based specifications to act as alternative means of design of concrete mixes. Despite this, a dominant assumption among professionals in the industry is that the dura- bility of a concrete mixture is directly proportional to its binder content. This may result in uneconomical, unsustainable and often non- durable concretes due to various implications of high cement contents, such as thermal effects, higher risks of alkali-silica reaction, dura- bility problems associated with higher paste contents, etc.
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