Recycling concrete not only reduces the use of virgin aggregate but also decreases the pressure on landfills. As a result, recycled coarse aggregate (RCA) is extensively recommended for new construction projects. However, the flexural behavior of corroded reinforced recycled aggregate concrete (RAC) beams is uncertain. The experimental research presented in this paper was performed to investigate the flexural behavior of corroded reinforced RAC beams compared to that of corroded reinforced natural aggregate concrete (NAC) beams and consequently explore the possibility of using RAC beams in corrosive environments. Four different percentages of RCA in total mass of coarse aggregate in concrete mixtures (0%, 33%, 66%, and 100%) and two different concrete strengths (C30, C60) were the governing parameters. The electrochemical method was adopted to accelerate steel corrosion. Full-scale tests were performed on eight simply supported beams until the failure load was reached. Comparison of load-deflection behavior, crack patterns, failure modes, ductility, and ultimate flexural capacity of corroded reinforced NAC and RAC beams was made based on the experimental results obtained. The comparison results show that the flexural behavior of corroded reinforced RAC beams with an appropriate percentage of RCA is satisfactory compared to the behavior of NAC beams.

In this research, a wave-drag modulus nondestructive testing method was proposed to predict the compressive bearing capacity of damaged wood components. Using an ancient Chinese building as a case study, internal and external inspections were performed to obtain defect data and related tree species information. Using the same tree species, wave-drag modulus and scale tests were carried out to predict the residual bearing capacity when there was damage in the form of internal cavities or edge material reduction and to compare the damage and loss experimental data. The results show that the internal defect combination model established by two nondestructive testing methods (stress wave and impedance meter) based on the weight distribution can accurately determine the internal damage condition of wood components. There was a significant correlation between wave-drag modulus and compressive strength along the wood grains. The measured values of wood components with different defects were consistent with the theoretical values predicted by the wave-drag modulus, which can effectively improve the prediction of residual bearing capacity. In addition, it was determined that edge material reduction is more destructive to a wood component than the presence of an interior cavity. Thus, the wave-drag modulus can quickly locate vulnerable sections and provide a relevant basis for judging the material condition of wood components in ancient buildings.

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