Effects of alternative aggregates on concrete strength

Worldwide, large quantities of solid waste are generated by construction and demolition (C&D) activities and the car industry. At the same time, the availability of landfill space is diminishing, and most industrialized nations are actively promoting recycling procedures to reduce the amount of waste going to landfill. Governments have also set up regulatory bodies to provide standards and protocols for these procedures. Environmental benefits and reduced concrete production costs are some of the advantages of using recycled materials. Given these worldwide trends, it is essential to consider recycling some of the solid waste from the construction industry and used tires from the car industry to supplement natural aggregates in the production of concrete for the construction industry. This papers discusses the on-going research at La Trobe University on the use of recycled aggregates such as crushed concrete, crushed brick and rubber chips in the production of concrete. The effects of partial or total replacement of normal-weight aggregates with recycled aggregates on the strength of concrete were investigated. Different types and proportions of aggregate replacements were studied to establish which protocols provided the best options. It was found that concrete mixes produced with recycled aggregates produced acceptable concrete with reduced production costs.