Assessment of expansive concrete with recycled aggregates properties under free and restraint conditions

Abstract

This review synthesizes serviceability evidence for expansive concrete with recycled aggregates (RAC) under free and restrained conditions in building applications. Uniaxial compression is interpreted in the standard cylinder convention (?100*200 or ?150*300; h/d = 2:1), with chord modulus referenced to an explicit ASTM C469 stress window; ASTM C157 informs free length change, and ASTM C1581 provides a relative restrained-cracking indicator. Across digitizable datasets, RAC shows a lower elastic modulus and slightly larger peak strain than NAC at a given strength. With expansive systems, free deformation capacity increases, whereas restraint moderates’ deformation and raises apparent stiffness. We supply a traceable source register and typical ranges for screening, and recommend a minimal verification suite (strength, chord modulus, free length change, one restrained method) with equivalent restraint stiffness and key environmental assumptions reported.