In the present paper, a digital image correlation (DIC) method is used to study the development of fracture process zones (FPZ) of different concrete materials in three-point bending test. Different concrete materials including original concrete, rubber concrete, self-compacting rubber concrete and pervious concrete are investigated. Firstly, the image of the FPZ and the crack opening displacement (COD) in FPZ is obtained by acquiring strain field and displacement field information. The relationship between the development of FPZ and the mechanical properties is further studied. It is found that there is a strong correlation between the FPZ and the post-peak strength reduction of concrete. The development characteristics of FPZ of different concrete materials are analyzed. The addition of rubber will result in stronger strain concentration in pre-peak stage compared to original concrete, and the FPZ will emerges at the earlier loading stage, but it can enhance the crack resistance of concrete in the post-peak stage. Self-compacting rubber concrete was observed to have higher bearing capacity and cracking resistance during fracture than that of the others. Pervious concrete has weak resistance to fracture, and there is almost no decline of the FPZ development rate in fracture process.

本文采用数字图像相关（DIC）方法研究了三点弯曲试验中不同混凝土材料的断裂过程带（FPZ）的发展。研究了不同的混凝土材料，包括原始混凝土，橡胶混凝土，自密实橡胶混凝土和透水混凝土。首先，通过获取应变场和位移场信息，获得FPZ的图像和FPZ中的裂纹张开位移（COD）。进一步研究了FPZ的发展与力学性能之间的关系。发现在FPZ和混凝土的峰后强度降低之间有很强的相关性。分析了不同混凝土材料FPZ的发展特点。与原始混凝土相比，橡胶的添加将在峰前阶段导致更强的应变集中，FPZ将在加载早期出现，但它可以增强峰后阶段的混凝土抗裂性。观察到自密实的橡胶混凝土在断裂过程中具有比其他更高的承载能力和抗裂性。渗透混凝土的抗断裂性能较弱，并且在断裂过程中FPZ的发展速度几乎没有下降。