Fracture experiments of three‐point bending notched granite beams were performed under cyclic loading using digital image correlation (DIC) and acoustic emission (AE) techniques. The damage evolution process of the specimen under cyclic loading was analysed on the basis of AE ring count and b value. The strain and displacement fields and the fracture process zone (FPZ) ahead of the crack tip were revealed by DIC. The results showed that the AE characteristics of rock fracture indicated a noticeable Kaiser effect in the stage of cyclic loading and unloading. Moreover, when the loading force reached 70% of its peak value, the AE characteristics showed the Felicity effect. The damage produced during the loading‐unloading process contributed to the development of the cracks leading to the catastrophic fracture. Besides, a relatively high loading rate was found to help to suppress the development of the FPZ at the crack tip.

中文翻译：

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DIC和AE技术在循环荷载作用下缺口花岗岩梁断裂损伤的实验研究。

使用数字图像相关（DIC）和声发射（AE）技术在循环载荷下进行了三点弯曲缺口花岗岩梁的断裂实验。根据AE环数和b值分析了循环载荷下试样的损伤演化过程。值。DIC揭示了裂纹尖端之前的应变和位移场以及断裂过程区（FPZ）。结果表明，在循环加载和卸载阶段，岩石破裂的声发射特征表明了明显的Kaiser效应。此外，当加载力达到其峰值的70％时，AE特性显示出Felicity效应。装卸过程中产生的损坏促成了导致灾难性断裂的裂纹的发展。此外，发现较高的加载速率有助于抑制裂纹尖端处的FPZ的发展。