Using concrete aggregates” defines manufactured sand to
Using Recycled Concrete Aggregate (RCA) is one of the methods, which has been receiving increased attention in civil industry as a sustainable alternative to natural aggregates not only with a low carbon footprint but also to decrease the solid demolition waste. Basically, by reducing the amount of mortar in the new RCA concrete, cement consumption will decrease. After World War II, the use of demolished concrete as aggregate for new concrete started in Europe (Wainwright et al., 1994). However, as soon as the demand for aggregate could be met by available natural aggregate, recycling was basically abandoned (Buck, 1976). Some countries have had some kind of standards and guideline for RCA, albeit not for RAC. Since 1982, the ASTM “Standard specification for concrete aggregates”, C33-82 (ASTM C33-82) defines coarse aggregate such that it includes crushed hydraulic cement concrete, and ASTM 125-79a (ASTM 125-79a) “Standard definitions of terms relating to concrete and concrete aggregates” defines manufactured sand to include hydraulic-cement concrete, and there are no longer technical barriers to the use of recycled concrete as aggregates in the United States.
In Japan, the Building Contractors’ Society of Japan (BCSJ) issued a “Proposed standard for the use of recycled aggregate and recycled aggregate concrete” in 1977 (Hansen, 1986). However, the recycling law was established in 1991 to control the increase of waste and to promote recycling of useful resources (Noguchi and Tamura, 2001). In the Netherlands, a proposal for a Dutch standard for recycled concrete as aggregate for production of new concrete was developed by CUR (Commissie voor Uitvoering van Research ingesteli de Betonvereniging). This standard allows using up to 20% by weight of the total coarse or fine aggregates to be RCA (Hansen, 1986).
In the United Kingdom, the New British Standard Guide 6543, “Use of industrial by-products and waste materials in buildings and civil engineering”, covers the use of demolition waste and other waste materials in both road construction and buildings. In Russia, since 1984 NlIZBH of the former USSR Research Institute for Concrete and Reinforced Concrete has allowed the use of coarse RCA in production of up to 20MPa concrete, including reinforced concrete, but not in pre-stressed concrete (Hansen, 1986). Denmark issued a modification to the regular concrete code in 1990, which allows the use of RAC for certain structural purposes under mild exposure conditions (Hansen, 1992).