基于中国和美国标准,对大质量混凝土中的温度和应力模拟进行比较分析,用于基于中国和美国标准的门结构
Jiaming Zhang1, Dan Zhou2, Xiangyu He1,3
1College of Water Conservancy and Hydropower Engineering, Hohai University, Nanjing 210098, China.
Materials (Basel, Switzerland)
|January 11, 2025
概括
中国和美国的大型混凝土温度控制标准显示了类似的结构温度和应力分布. 与美国标准相比,中国标准预测温度稍高,但拉力应力较低.
科学领域:
- 土木工程 土木工程是指土木工程.
- 结构工程 结构工程
- 材料科学 材料科学 材料科学
背景情况:
- 像水门和桥梁这样的大型混凝土结构中的水化热会导致温度诱导的裂,威胁到结构安全.
- 大型混凝土的国际温度控制标准对于设计和评估至关重要,中国和美国是领先的国家.
- 了解中国和美国标准之间的差异有助于跨国项目,并优化国家准则.
研究的目的:
- 为了比较中国和美国混凝土质量标准的温度和应力控制结果.
- 为国际项目提供洞察力,在温度控制设计中平衡成本和安全.
- 为改进国家标准提供经验证据.
主要方法:
- 使用ABAQUS软件 (2023版) 开发一个水门的有限元模型.
- 对于模拟温度和应力场的ABAQUS的二次开发.
- 根据中国和美国的温度控制标准对模拟结果进行比较分析.
主要成果:
- 总体温度和应力分布在中国和美国标准下是相似的.
- 中国标准预测的最大内部温度略高于美国标准 (≤1.7°C).
- 与美国标准相比,中国标准的最大拉力应力较低 (内部≤0.23MPa,表面≤0.56MPa).
结论:
- 中国和美国的标准都为大质量混凝土结构提供了有效的温度控制.
- 中国标准在减轻拉伸应力方面可能带来轻微优势,这可能会影响结构安全和成本效益.
- 这项比较研究为优化国际和国家混凝土质量温度控制指南提供了有价值的数据.
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