Concrete fracture toughness increase by embedding self-healing capsules using an integrated experimental approach
Concrete fracture toughness increase by embedding self-healing capsules using an integrated experimental approach
复制标题
使用综合实验方法通过嵌入自愈胶囊来提高混凝土断裂韧性
DOI：
10.1016/j.conbuildmat.2019.05.138
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发表时间：
2019
影响因子：
7.4
通讯作者：
D. Aggelis
中科院分区：
文献类型：
--
作者：
E. Tsangouri;F. Gilabert;N. De Belie;D. Van Hemelrijck;Xingyi Zhu;D. Aggelis
最近已经建立了一种修复混凝土裂缝的替代解决方案，即通过在浇注期间将修复剂嵌入混凝土中来自主愈合。该试剂被包含在小尺寸的胶囊中，随着裂缝的形成而破裂。当该试剂被释放到裂缝空隙中时，它快速固化，从而允许裂缝密封和机械修复。大部分的文献研究集中在愈合系统的设计和修复效率的评估。然而，有限的知识存在的宏观胶囊本身对混凝土力学行为的影响。这是一个至关重要的主题，因为愈合机制不应损害材料的机械性能。本文研究了考虑断裂本构模型的胶囊对损伤抗力的影响。与参考相比，具有胶囊的样品的断裂韧性增加高达35%。声发射被应用于评估胶囊对断裂过程的影响。事件定位表明断裂过程区扩展了40%。据证明，胶囊有益地有助于作为局部增强扰动裂纹路径和形成多个微裂纹（另外通过数字图像相关验证）。总之，一个完整的实验方案开发，突出混凝土韧性增强通过添加胶囊。
An alternative solution to repair cracks in concrete has been recently established, namely autonomous healing by embedding repair agent into concrete during casting. The agent is included into small-size capsules that break as cracks form. As the agent is released into the crack void, it solidifies fast permitting crack sealing and mechanical restoration. Most of literature studies focus on the healing system design and the repair efficiency assessment. However, limited knowledge exists on the effect of the macro-capsules themselves on concrete mechanical behaviour. This is a crucial subject as the healing mechanism should not compromise the material mechanical properties. The paper investigates the effect of capsules on damage resistance by considering fracture constitutive models. Fracture toughness of samples with capsules increases up to 35% compared to the reference. Acoustic emission is applied to assess the capsules effect on fracture processes. Events localization indicates fracture process zone expansion by 40%. It is proven that the capsules beneficially contribute as local reinforcement perturbating the crack path and forming multiple microcracks (additionally verified by Digital Image Correlation). In summary, an integrated experimental protocol is developed to highlight the concrete toughness enhancement by adding capsules.