在冷解周期下,混凝土的动态压缩损伤构造性纠正
Ankui Hu1,2,3, Xinglin Chen3, Xinyu Du3
1Key Laboratory of Fluid and Power Machinery, Xihua University, Ministry of Education, Chengdu 610039, China.
Materials (Basel, Switzerland)
|March 27, 2025
概括
这项研究使用有限元分析开发了融条件的具体构成模型. 该模型准确地预测了动态压缩下混凝土损坏的进展,有助于工程应用.
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
- 计算力学 计算力学 计算力学
背景情况:
- 混凝土结构容易受到冷解周期的损坏,影响其机械性能和长期性能.
- 了解混凝土在动态负荷和环境压力因素下的构成性行为对于结构完整性至关重要.
- 现有的模型可能无法完全捕捉动态压缩下混凝土冷解引起的复杂损伤机制.
研究的目的:
- 开发和验证在融条件下经过单轴动态压缩的混凝土的构成模型.
- 在冷解环境下进行动态压缩试验时调查混凝土损坏的进展情况.
- 为了提高暴露于恶劣环境因素的混凝土结构的数值模拟的准确性.
主要方法:
- 使用有限元分析 (FEA) 来建模混凝土的温度场.
- 一个顺序合的热应力分析将温度数据集成到应力场中.
- 数字模拟使用修改的内在和损伤可塑性模型评估了混凝土损伤的进展,在单轴应力-张力关系中调整参数.
主要成果:
- 开发的构成模型与融和动态压缩下混凝土的实验结果密切一致.
- 该研究成功模拟了混凝土损伤的进展,突出了损伤因素的影响.
- 有限元分析为理解热力机械损伤合提供了一个强大的框架.
结论:
- 修改后的构成模型提供了一种可靠的方法来模拟融和动态负载下的混凝土行为.
- 这些发现有助于改善寒冷气候中的混凝土结构的数值模拟.
- 这项研究对接触融周期的混凝土基础设施的设计和维护具有实际意义.
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