实验和数值研究的混凝土断裂行为与多个裂基于中型模型
Zhanliang Wang1, Wei Zhang1, Yiqun Huang1
1School of Civil Engineering, Fujian University of Technology, Fuzhou 350118, China.
Materials (Basel, Switzerland)
|September 28, 2023
概括
混凝土的多个裂稍微增加了承载能力. 这项研究发现,存在额外的裂,特别是长度增加或距离缩短时,增强了混凝土的性能.
科学领域:
- 土木工程 土木工程是指土木工程.
- 材料科学 材料科学 材料科学
- 结构工程 结构工程
背景情况:
- 混凝土的断裂行为对结构完整性至关重要.
- 了解多个裂的影响对于准确的结构分析至关重要.
- 现有的模型往往简化了破裂混凝土复杂的断裂机制.
研究的目的:
- 为了研究多个裂对混凝土破裂行为的影响.
- 量化裂长度和距离对承载能力的影响.
- 开发和验证一个数值模型,用于预测具有多个裂的混凝土断裂.
主要方法:
- 在双裂混凝土样本上进行了实验性三点曲 (TPB) 试验.
- 开发了一种数值半模型,其中包含聚合物,砂和接口过渡区 (ITZ) 的凝聚性元素.
- 对实验数据验证了中型模型,并分析了断裂期间的能量演变.
主要成果:
- 双裂标标本显示的承载能力略高于单裂标本.
- 增加第二裂纹长度或减少裂纹距离导致更高的混凝土承载能力.
- 在承载能力和模式II能耗之间观察到线性关系.
结论:
- 主裂附近的多个裂可以在模式I主导的断裂测试中略微提高承载能力.
- 这种增强归因于由于存在多个裂,增加了内部能量消耗.
- 开发的中型模型准确地模拟了多个裂的混凝土断裂行为.
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