Experimental Study on Residual Compressive Strength of Recycled Aggregate Concrete Under Fatigue Loading

Abstract

Using recycled aggregate for producing concrete is an effective way to realize the resource utilization of construction and demolition waste. Understanding the variation law of the residual compressive strength of recycled aggregate concrete (RAC) under fatigue loading is significant for its practical application under repeated loads. Thus, this paper conducted uniaxial compression fatigue and static-load tests on recycled aggregate concrete with the different replacement ratios of recycled coarse aggregate, analyzed the probability distributions of the fatigue life and residual compressive strength of RAC and natural aggregate concrete (NAC), and revealed the attenuation law of their residual compressive strength. In addition, it studied and compared the evolution of fatigue damage to NAC and RAC by defining a damage variable based on residual compressive strength. The results show that the fatigue life of the RAC and NAC matches the two-parameter Weibull distribution, and their residual compressive strength follows the normal distribution. The attenuation law of the residual compressive strength of the RAC is similar to that of the NAC. In the initial stages of the fatigue loading, the attenuation is small, and the attenuation rate of the residual compressive strength of the RAC and NAC is low. In contrast, it gradually accelerates in the later stages; a sudden and significant decrease in the concrete strength is noticed in the final stage near failure. Compared with the NAC, the damage to the RAC develops faster in the initial stages of fatigue loading and slower in the later stages.