AASHTO PS

Abstract

This specification covers coarse aggregate derived from reclaimed concrete for use in hydraulic cement concrete. The specification is not intended for use when lightweight, high-density, or other specialty concrete applications are required. When aggregate materials are properly processed and manufactured to the requirements of this specification, combined and mixed in accordance with the appropriate requirements, and placed, consolidated, and cured properly, a concrete structure of acceptable strength and durability can be produced. Introducing reclaimed concrete aggregate (RCA) into concrete, however, requires the use of quality control and quality assurance procedures to ensure that deleterious materials that might be present in the reclaimed concrete aggregate will not adversely impact the quality of the concrete product. <br>Best practice applications for using reclaimed concrete aggregate in concrete shall consist of concrete pavements, cement-treated base courses, sidewalks, median barriers, curbings, and other nonstructural applications. <br><strong>Note 1</strong>&#8212;Caution should be exercised if reclaimed concrete aggregate is considered for use in structural applications. The presence of deleterious materials and the variability in the source concrete may produce inconstant volumetric properties and affect the properties of the concrete produced. Two properties of concern include dimensional stability and creep. <br>Because reclaimed concrete aggregate is a recycled material, various state and local jurisdiction laws and regulations may be applicable. The user of this specification is cautioned to contact state and local environmental and other local regulators to determine what requirements are appropriate.