新型分数方法用于用于桥梁工程应用的混凝土爬行建模
Krzysztof Nowak1, Artur Zbiciak1, Piotr Woyciechowski1
1Faculty of Civil Engineering, Warsaw University of Technology, Al. Armii Ludowej 16, 00-637 Warsaw, Poland.
Materials (Basel, Switzerland)
|August 14, 2025
概括
这项研究通过使用先进的碎形学模型,提高了在桥梁中的混凝土爬行预测. 研究结果显示,矿物添加剂显著减少了爬行,提高了结构耐用性和安全性.
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:
- 混凝土的爬行是桥梁结构寿命的一个关键因素.
- 精确的混凝土爬行模型对于现代建筑技术至关重要,例如平衡悬臂和增量发射.
- 现有的设计代码,如欧元代码2,可能无法完全捕捉所有混凝土混合物的爬行行为.
研究的目的:
- 调查混凝土混合物成分,特别是高炉渣含量和空气吸附对混凝土爬行的影响.
- 校准和验证先进的碎形风学模型 (Kelvin-Voigt和Huet-Sayegh),以改善爬行预测.
- 将拟议模型的准确性与欧元码2等现有标准进行比较.
主要方法:
- 实验室对9种混凝土混合物进行了测试,这些混凝土混合物的高炉含量 (0%,25%,75%) 和空气排放量各不相同.
- 通过将粘性元素替换成碎形元素来校准碎形风湿学模型.
- 用于爬行预测的校准模型的实验数据验证.
主要成果:
- 碎形学模型显示与实验爬行数据的高度一致.
- 与传统方法相比,提出的模型显著提高了爬行预测的准确性.
- 当将模型预测与欧元代码2进行比较时,观察到高达64%的差异,特别是对于无渣混凝土.
结论:
- 矿物添加剂,如高炉渣,在减少混凝土爬行菌株方面发挥着至关重要的作用.
- 在结构设计计算中必须考虑单个混凝土混合物特性,以准确的长期行为分析.
- 提出的先进建模方法为分析长期结构行为提供了更高的精度,有助于构建更安全,更持久的混凝土基础设施.
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