ABSTRACT
Abstract Although 40% of demolition waste in the UK is recycled i t is mainly for low grade applications suc h as fill and hardcore. Highe r grade utilisation such as in concrete has been discouraged by a lack of suitable specifications. Th e main UK Standard for aggregate in concrete i s for natural aggregates, and the only other Standard s quoted i n job specifications are for lightweight aggregates and blastfurnace slag . Nevertheless , there are ways in which recycled aggregate could be used within the context of British Standards. Firstly, in the Standard fo r concrete, specific allowance is made for aggregates not conforming to British Standard provided the properties of the concrete are satisfactory, but this places an extra duty of care on the specifier. Secondly , there is a British Standard Guide on the use of industrial by-products and waste materials in building and civil engineering which gives specific guidance on the use of demolition waste in construction, but there is little knowledge and virtually no use of this Standard. Th e UK Department of Transport has recently revised it s specification for highway works and this now permits the use of crushed concrete complying with the quality and grading requirements of BS882 as an aggregate for pavement concrete.
