温度控制添加剂对飞灰混凝土收缩和机械性能的影响:实验和建模
Yingda Zhang1, Haiyang Li1, Haojie Zhang1
1School of Architecture and Civil Engineering, Xihua University, Chengdu 610039, China.
Materials (Basel, Switzerland)
|August 28, 2025
概括
一种新的温度控制添加剂 (TCA) 有效地减少了质混凝土的收缩和热裂纹. 最佳的0. 10%TCA剂量显著改善了强度,并导致更准确的收缩预测模型.
科学领域:
- 土木工程
- 材料科学
- 建筑技术
背景情况:
- 大量混凝土结构面临着早期收缩和热裂的挑战.
- 控制内部温度升高对于结构完整性至关重要.
- 现有的模型往往无法准确预测改造混凝土混合物的收缩.
研究的目的:
- 引入和评估用于飞灰混凝土的新型温度控制添加剂 (TCA).
- 研究TCA对收缩,热性能和机械稳定性的影响.
- 开发一个改进的混凝土收缩预测模型,其中包括TCA.
主要方法:
- 实验评估四种飞灰混凝土混合物,含有不同剂量的TCA (0-0.15%).
- 控制环境测试以测量收缩和温度升高.
- 实验结果与现有的收缩预测模型进行比较 (Eurocode 2, fib Model Code 2010, AS 3600, Bazant B4).
- 一个修改后的半经验预测模型的开发.
主要成果:
- 在28天后,最佳的TCA剂量减少了27. 3%的收缩,并增加了12. 2%的压力强度.
- 现有的模型高估了缩率高达294%.
- 修改后的模型将预测误差降低到10%,变化系数为0.08.
结论:
- 这种新型的TCA有效地缓解了混凝土的早期收缩和热问题.
- 一个修改后的预测模型准确地捕捉了TCA对混凝土收缩和水分传输的影响.
- 这项研究为设计使用TCA的先进混凝土系统提供了宝贵的见解.
相关概念视频
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01:22Mass Concreting
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01:14Design Example: Managing Concrete Workability
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01:27Shrinkage in Concrete
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01:21Drying Shrinkage
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01:27Cold Weather Concreting
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