在温度应力测试机器下,研究添加氧化的混凝土早期破裂情况
Zixuan Li1, Zheng Chen1, Junting Li1
1College of Civil and Transportation Engineering, Shenzhen University, Shenzhen 518060, China.
Materials (Basel, Switzerland)
|January 11, 2024
概括
混凝土中的氧化添加剂 (MEA) 通过改善应力放松和减少自我收缩来增强裂纹耐受性. 优化的MEA内容有效地减轻了早期的混凝土裂,根据预测模型的验证.
科学领域:
- 材料科学 材料科学 材料科学
- 土木工程 土木工程是指土木工程.
- 建筑材料 建筑材料
背景情况:
- 混凝土裂是建筑业的一个重大挑战.
- 约束应力是早期混凝土裂的一个关键因素.
- 氧化添加剂 (MEA) 可以提高混凝土的抗裂性能.
研究的目的:
- 研究MEA对混凝土变形和机械性能的影响.
- 开发一个预测模型,用于早期控制混凝土应力.
- 评估MEA在增强混凝土抗裂能力方面的潜力.
主要方法:
- 使用温度应力测试机器测试具有不同MEA含量的混凝土样本.
- 进行自由和完全受约束的变形试验.
- 开发一个预测模型,整合应力放松,自身缩,温度变形和弹性模量.
主要成果:
- 添加MEA会影响热膨胀系数.
- 3%和8%的MEA抵消了自我收缩,而5%则增加了它.
- MEA增强了膨胀应力,裂应力和应力放松,改善了抗裂性能.
- 开发的模型准确地预测了拉力约束应力.
结论:
- MEA有效地提高了混凝土的抗裂性能,特别是在特定剂量的情况下.
- 这项研究提供了一个验证的模型来预测早期的克制压力.
- 优化MEA含量对于最大限度地提高抗裂纹效益至关重要.
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