National Concrete Pavement Technology Center

Project description

Some industrial wastes (often called industrial byproducts, waste products, or waste materials) can be used as replacements for virgin aggregates or pozzolans, reducing the need for additional virgin material and saving landfill space that would otherwise be used for industrial waste disposal. These industrial wastes include fly ash from coal combustion that does not meet typical specifications or agency requirements (sometimes called "off-spec" or "near-spec" ash), bottom ash, municipal solid waste incinerator (MSWI) ash, ground glass, foundry sand, recycled concrete aggregate (RCA) or mixed rubble from construction and demolition (C&D) recycling facilities, and other materials. Research and field studies have shown that materials such as these can be beneficially used in several bound and unbound applications in concrete paving projects. This document discusses the use of industrial wastes in concrete paving applications. Potential applications for using these wastes in highway infrastructure are identified, and design considerations are discussed. Information is provided to support evaluation of these materials for use. Approaches and considerations for agency approval of these products are also presented.