In this study, the crack evolution process of crumb rubber concrete (CRC) in a four-point bending tensile test was monitored using the acoustic emission (AE) technique. The peak frequency, distribution characteristics of the AE source, and the damage process based on the AE ring count during the crack evolution were analyzed. The test results revealed that the addition of rubber particles decreased the brittleness of cracks and improved the ductility of the concrete during the macro-cracking process. The AE positioning method could effectively monitor the evolution process of micro-cracks inside the concrete. Additionally, based on the statistical results of the AE source events and energy distribution, the position of macroscopic cracks could be predicted, and the random distribution of micro-cracks could be characterized. By introducing the Weibull distribution to describe the random growth process of micro-cracks, the damage inside the concrete could be qualitatively predicted. As the rubber particle content increased, the inherent micro-cracks inside the concrete also increased. The damage inside the concrete was biased toward the crack nucleation stage.

在这项研究中，使用声发射（AE）技术监测了四点弯曲拉伸试验中的碎屑橡胶混凝土（CRC）的裂纹发展过程。分析了裂纹扩展过程中的峰值频率，声源的分布特性以及基于声环数量的损伤过程。试验结果表明，橡胶颗粒的添加降低了裂纹的脆性，并改善了宏观裂纹过程中混凝土的延展性。声发射定位方法可以有效地监测混凝土内部微裂纹的演变过程。此外，根据声源事件和能量分布的统计结果，可以预测宏观裂纹的位置，并可以表征微裂纹的随机分布。通过引入威布尔分布来描述微裂纹的随机生长过程，可以定性地预测混凝土内部的损伤。随着橡胶颗粒含量的增加，混凝土内部固有的微裂纹也增加了。混凝土内部的损坏偏向裂纹成核阶段。