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This chapter briefly discusses some alternatives to Portland cement. These include calcium aluminate cement (CAC) that has been in use for a hundred years or so and some cements that have more limited use and/or are currently being developed and are not yet in widespread use. This latter group is of particular interest because of their potential of being produced at lower temperatures than Portland cement, thereby requiring less energy for production; this is a major concern for Portland cement in relation to sustainability issues, particularly carbon emissions. The setting time of CAC is about 30 minutes longer than that of a typical Portland cement. There are, however, several current important uses of CAC and concrete that takes advantage of its superior properties compared to other cements: alkali-activated cements, geopolymer cements, waste-derived cements and magnesium oxide-based cements.

Civil engineers are responsible for the production, transport, placing, compacting and curing of fresh concrete. This chapter considers the properties when freshly mixed, between placing and setting, and during the early stages of hydration. Experience in mixing, handling and placing fresh concrete quickly gives concrete workers (and students) a subjective understanding of the behaviour and an ability to recognise 'good' and 'bad' concrete. Rigorous measurement of the flow behaviour of any fluid is normally carried out in a rheometer or viscometer of some sort. A large number of simple but arbitrary tests for consistence or workability have been devised over many years, some only being used by their inventors. In the Vebe test, the response of the concrete to vibration is determined. The flow table test was devised to differentiate between high workability mixes. Although concrete remains sufficiently workable for handling and placing for some time after it has been mixed, its consistence continually decreases.

The Concrete Solutions series of International Conferences on Concrete Repair began in 2003 with a conference held in St. Malo, France in association with INSA Rennes. Subsequent conferences have seen us partnering with the University of Padua in 2009 and with TU Dresden in 2011. This conference is being held for the first time in the UK, in associ