Abstract: The constitutive relation of recycled aggregate concrete was constructed based upon the stress-strain relation under uniaxial compression with varying replacement ratio of recycled aggregate and water-cement ratio. With road waste concrete as recycled aggregate, 45 prismatic specimens with dimensions of 150 mm×150 mm×300 mm were prepared for test. Results unveiled that with the increase of the replacement ratio of recycled aggregate, the peak stress f_c of recycled aggregate concrete declined at first, and then climbed slightly but decreased afterwards; peak strain ε₀ augmented firstly and then decreased. With the increase of water-cement ratio, peak stress f_c presented different variation trends—yet in general a decline trend—due to varied replacement ratio; peak strain ε₀ increased firstly and then remained unchanged or decreased slightly. In general, the peak stress of recycled aggregate concrete is slightly smaller than that of natural concrete, and strain slightly greater than that of natural concrete. The research results offer technical support and reference for the popularization and application of recycled aggregate concrete.

Key words: recycled aggregate concrete, replacement rate, water-cement ratio, uniaxial compression, constitutive relation