This report describes a 7 month study into the use of recycled and secondary aggregates (RSA) in foamed concrete. The project builds upon the successful outcome of a previous study (MAGCON), which identified foamed concrete as the concrete formulation with the greatest scope for reducing primary aggregate consumption, mainly due to its high air content. In addition, the MAGCON work demonstrated the ability of foamed concrete to easily incorporate two RSA materials, namely demolition arisings fines and conditioned fly ash, whilst achieving enhancements in performance.
Given this background, this study aimed to explore the full potential of RSA foamed concrete and thereby provide designers, specifiers and users of foamed concrete with a greater flexibility in the selection of RSA type. The specific objectives of the work were to assess (i) the performance of a wider range of RSA in foamed concrete both in the laboratory and on large-scale production, (ii) the market for RSA in foamed concrete in the UK, (iii) the overall environmental impact and (iv) cost-effectiveness of RSA foamed concretes, thereby leading to sustainable technologies that are readily exploitable. In addition, tentative guidance on the specification and quality control of RSA foamed concrete was developed and the findings of the study disseminated.