To study the dynamic behavior and impact damage and failure of concrete materials and structures, a dynamic damage model was reformulated under the framework of the non-local peridynamic theory in this paper. The stretch rate of material bonds, equivalent to the strain rate in classical continuum mechanics, was introduced, and a rate-dependent peridynamic model describing the dynamic damage and failure of concrete materials was then proposed, taking both the dynamic failure of bonds and the rate-sensitivity of damage evolution under different stretch rate into account. The connection between the stretch rate and strength and tensile and compressive failure of concrete materials was established in the peridynamic model. To verify the proposed dynamic damage model for concrete failure, several typical examples simulating the mixed-mode fracture of concrete specimen were investigated. The failure mode, crack propagation paths and the crack propagation speed in the specimen in different cases were captured, which agree well with the experimental results and available numerical results. After model validation, the effect of the number and length of pre-existing cracks on the dynamic failure of concrete components was investigated further.

中文翻译：

---

冲击载荷作用下混凝土的近场动力学中与速率相关的动态损伤模型

为了研究混凝土材料和结构的动力行为和冲击损伤与破坏，本文在非局部近场动力学理论的框架下重新构建了动力损伤模型。引入了材料键的拉伸率，相当于经典连续介质力学中的应变率，然后提出了描述混凝土材料动态损坏和破坏的速率相关近场动力学模型，同时考虑了键的动态破坏和速率- 考虑不同拉伸率下损伤演变的敏感性。在近场动力学模型中建立了混凝土材料的拉伸率和强度以及拉伸和压缩破坏之间的联系。为了验证所提出的混凝土破坏动态损伤模型，研究了几个模拟混凝土试件混合模式断裂的典型例子。捕获了试样在不同情况下的破坏模式、裂纹扩展路径和裂纹扩展速度，与实验结果和现有数值结果吻合良好。模型验证后，进一步研究了预存裂缝的数量和长度对混凝土构件动态破坏的影响。