混凝土结构的断裂分析:基于边界效应模型的预测
Gang Han1, Xiangyu Han2, Yi Ji3
1Department of Mechanical Engineering, University of Western Australia, Perth, WA 6009, Australia.
Materials (Basel, Switzerland)
|May 7, 2025
概括
边界效应模型 (BEM) 有效地将小型混凝土样本测试与大型结构故障联系起来. 这种断裂分析工具准确地预测了具体的行为和尺寸效应,并结合了总体影响和统计分析,以获得可靠的结果.
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
- 结构分析 结构分析
背景情况:
- 对混凝土结构的精确断裂分析需要模型,将小规模测试结果与大规模结构故障联系起来.
- 现有的模型往往缺乏处理各种样本类型的能力或结合总量大小等关键因素.
- 边界效应模型 (BEM) 已经发展了20多年,以解决混凝土断裂分析中的这些局限性.
研究的目的:
- 评估线性边界效应模型 (BEM) 对其预测混凝土断裂行为和尺寸效应的能力.
- 证明BEM能够将小型混凝土样本测试结果与大型结构的故障联系起来.
- 调查聚合物大小对混凝土破裂的影响及其纳入BEM.
主要方法:
- 利用了从文献中获得的混凝土断裂结果的综合数据集以及来自138次三点曲 (3-P-B) 试验的新实验数据.
- 分析的标本有不同的切口深度 (没有切口,浅,深) 和不一致的尺寸.
- 将统计分析集成到BEM中,以考虑实验分散,并提高预测可靠性.
主要成果:
- 线性BEM准确地模拟了混凝土的断裂过程区域 (FPZ) 和准脆断裂行为.
- 通过可靠的预测,BEM成功地将小样本行为与大结构性能联系起来.
- 该模型有效地纳入了平均聚合体大小 (dav) 对断裂的影响,这是许多其他模型中缺乏的特征.
- 在BEM中统计整合提高了预测最大断裂负载的可靠性.
结论:
- 线性BEM是一种简单,可靠和准确的工具,用于在各种尺度上进行混凝土断裂分析.
- 由于BEM能够结合总体尺寸和统计变异的能力,使其成为工程师们的有价值的预测模型.
- 该模型的有效性得到证实,用于预测有和没有的混凝土标本和结构中的断裂行为.
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