STRESS-STRAIN RELATIONSHIP OF RECYCLED COARSE AGGREGATE CONCRETE

The stress-strain relationship of recycled coarse aggregate concrete is the bridge to realize its mechanical analysis from material level to structural level, and becomes the cornerstone of the basic theory of recycled coarse aggregate concrete structure. The research progress made by the author's group in the stress-strain relationship of recycled coarse aggregate concrete over the years was introduced. The influence of complex interfacial transition zones on the failure behavior of recycled coarse aggregate concrete was investigated by using the method of modeling recycled coarse aggregate, and the microscopic damage and evolutionary mechanism of recycled coarse aggregate concrete were revealed. From static to dynamic loading, the experimental studies of stress-strain behaviors of recycled coarse aggregate concrete were carried out systematically under different working conditions, the influence of loading conditions on the internal stress and deformation of recycled coarse aggregate concrete was investigated, and the corresponding mechanical and mathematical models were established. Furthermore, considering the temporal and spatial variability of the performance of recycled coarse aggregates, the probabilistic distribution characteristics of the mechanical response of recycled coarse aggregate concrete were found, and the stochastic damage constitutive relationship of recycled coarse aggregate concrete was proposed. Based on the obtained constitutive model, the time-dependent reliability analysis and dynamic non-linear analysis of recycled coarse aggregate concrete components and structures were carried out, providing theoretical support for the safe application of recycled coarse aggregate concrete in practical engineering. Relevant conclusions were extracted and future research work was prospected.