大量混凝土倒装块的环境温度和合理的散热系数之间的关系
Jiaming Zhang1,2, Hongshi Zhang3, Yunpeng Zhao1
1College of Water Conservancy and Hydropower Engineering, Hohai University, Nanjing 210098, China.
Materials (Basel, Switzerland)
|May 25, 2024
概括
混凝土边缘需要比平面更强的绝缘,以防止裂纹和材料浪费. 这项研究通过分析温度和应力场来优化绝缘,开发有效防裂模型.
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:
- 目前的大型混凝土表面的绝缘实践往往是均的,忽视了平面和边缘之间的差异散热.
- 大质量混凝土结构的边缘经历了更快的热损失和应力度,增加了裂纹风险.
- 优化不同混凝土表面面积的绝缘对于能源效率和结构完整性至关重要.
研究的目的:
- 调查环境温度和表面散热对早期混凝土温度和应力场的影响.
- 为了确定质量混凝土结构的平面和边缘部分的最佳,差异化的表面绝缘措施.
- 开发基于环境条件的绝缘要求的预测数学模型.
主要方法:
- 使用南京的一座桥梁支柱作为案例研究,开发了一个有限元模型.
- 模拟探索了不同环境温度和表面散热系数的影响.
- 数学模型是从模拟结果中得出的,以将环境温度与所需的散热系数相关联.
主要成果:
- 确定了合理的散热系数,以防止在不同的环境温度下在平面和边缘表面发生裂纹.
- 与平面相比,边缘需要较低的散热系数,这表明需要加强边缘绝缘.
- 开发的数学模型显示出高精度 (平面R2为0.95,边缘R2为0.92) 并与有限元计算进行验证.
结论:
- 混凝土平面和边缘的差异化绝缘策略对于有效的裂预防和材料优化至关重要.
- 该研究提供了经过验证的数学模型,用于根据环境温度确定适当的绝缘级别.
- 研究结果为绝缘大质量混凝土结构提供了实际指导,提高了能源效率和耐用性.
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