Fracture analysis of multifunctional fiber-reinforced concrete using phase-field method
Fracture analysis of multifunctional fiber-reinforced concrete using phase-field method
复制标题
多功能纤维混凝土断裂相场分析
DOI：
10.1016/j.ijsolstr.2023.112493
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发表时间：
2023
影响因子：
3.6
通讯作者：
Najafi, Ahmad R.
中科院分区：
文献类型：
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作者：
Sadighi, Amirreza;Maghami, Ebrahim;Khaneghahi, Mohammad Houshmand;Kamireddi, Divya;Rahmaninezhad, Seyed Ali;Farnam, Yaghoob;Sales, Christopher M.;Schauer, Caroline L.;Najafi, Ahmad R.
本文对一种新型纤维增强混凝土砌块——多功能纤维增强混凝土（MFRCs）的断裂响应进行了数值分析。在MFRCs中，纤维被包裹了一层外壳。这将允许结构用于多种用途，包括混凝土自修复。本研究采用相场断裂框架进行。分析了壳厚和纤维长径比等几何参数对MFRCs抗断裂性能的影响。由于壳体材料的选择还在研究中，在下一步的研究中，除了几何因素外，还将分析不同材料失配情况下壳体的临界能量释放率。此外，还研究了两种不同纤维的应用，聚酯纤维和聚丙烯纤维（其临界能量释放率几乎高出10倍）。所有结构都经历了三种加载条件：拉伸加载、压缩加载和三点弯曲。为了判断哪种结构的性能最好，考虑了每个案例研究中每个结构的峰值力和吸收能的值，并与其他结构的值进行了比较。结果表明，最有利的性能和结构取决于加载条件和材料组合。拉伸作用下，纤维长径比最小的MFRCs表现出的峰值力和吸收能均高于聚酯纤维。在压缩载荷下，所有模型和材料组都进行了相同的观察。在三点弯曲加载条件下，对于聚酯纤维的情况，得到了类似的结果，纤维长径比最小时力学响应最好。尽管如此，必须指出的是，在这种荷载条件下，壳体材料对结构的断裂响应起主导作用。聚丙烯纤维在不同的加载条件下也能增加峰值力。
In this paper, a numerical analysis has been conducted to predict the fracture response of a novel type of fiber-reinforced concrete blocks, called “multi-functional fiber reinforced concretes” (MFRCs). In MFRCs, fibers have been coated with a shell. This will allow the structure to be used for multiple purposes, including concrete self-healing. This study is conducted utilizing phase-field fracture framework. The shell thickness and the ratio of fiber length to diameter are the geometrical parameters whose effects on the fracture resistance of the MFRCs have been analyzed. As choosing the right shell material is under investigation, in the next step of the study, in addition to the geometrical factors, different material mismatch cases for the critical energy release rate of the shell has been analyzed. Moreover, the application of two different fibers, polyester fiber and polypropylene fiber (with almost 10 times higher critical energy release rate), are looked into. All the structures undergo three loading conditions: tensile loading, compressive loading, and three-point bending. In order to judge what configuration performs best, the values of peak force and absorbed energy of each structure in each case study have been taken into consideration and compared with those of other structures. It was seen that the most favorable performance and configuration depend on the loading condition and also the material set. Under tension, MFRCs with the lowest fiber length to diameter ratio exhibit the highest peak force and absorbed energy in the case of polyester fiber. The same observation was made for all models and material sets under compressive loading. Under three-point bending loading condition, for the cases of polyester fiber, similar results were obtained as the lowest fiber length to diameter ratio showed the best mechanical response. Having said that, it must be mentioned that shell material had a dominant effect on the fracture response of the structure under this loading condition. Polypropylene fibers also managed to increase the peak forces in different loading conditions.