‘Cement-free’ concrete

About

The major aim of this innovation is the development of a methodology for the prediction of the mechanical properties and workability of geopolymer ‘cement-free’ concrete based on the chemical composition of the raw materials and the development of a mix design process. Concrete is one of the most commonly used construction materials. However, the main drawbacks in the use of concrete are related to the use of cement and subsequently the high percentage of carbon dioxide emissions. Geopolymer concrete is a green construction material in which cement is replaced by waste materials (i.e. PFA, GGBS). 1 ton of cement production leads to almost 0.8 tons of CO2 emissions and therefore substitution of cement can lead to significant reduction of CO2 emissions. At the same time geopolymer has been found to be more durable than conventional concrete. Even if there is a continuously ongoing research on various types of geopolymer concrete, the construction industry has been very slow in the adoption and embracing of ‘geopolymer’ concrete as a replacement of ‘conventional’ concrete and this is mainly attributed to the limited knowledge on this field. The identification of the suitable materials and the design of geopolymer mix for specific strength and workability requirements is a complicated process. The proposed innovation is focused on the development of a ‘user friendly’ methodology for the calculation of suitable cement-free mix designs which will facilitate the extensive use of cement-free concretes in construction industry and especially for precast elements.