Sustainability of recycled concretes through life cycle assessment

A significant number of green concrete have been recently designed to meet the growing request of reducing construction industry impacts, saving raw materials and preventing industrial by-products’ discard. Between these, recycled aggregates coming from construction and demolition waste (CDW) and Black/Oxidizing Electric Arc Furnace (EAF) slag have been founded to be suitable for structural concrete applications, when used as replacement of natural coarse aggregates. However it is necessary to solve the arising question about how those recycled materials effectively improve the sustainability of concrete industry. A quantitative estimate of the environmental impacts’ related to the production of those concretes can be performed using several environmental indicators. In this section a review of the available environmental tools, useful to assess concrete impacts, is reported. Particularly Life Cycle Analysis (LCA) and abiotic depletion indicator can be satisfactorily applied to quantify the emission reduction due to the use of recycled aggregates instead of natural gravel in structural concrete. The procedure described in this section can be applied to determine the impacts of other recycled aggregates concretes, practically estimating the environmental footprint of the material.