在融环境下纳米TiO2-修改混凝土的机械性能
Chao Xu1, Lin Deng1,2, Dingtao Yang3
1School of Architecture and Civil Engineering, Huangshan University, 39 Xihai Road, Huangshan 245041, China.
Nanomaterials (Basel, Switzerland)
|August 27, 2025
概括
与普通混凝土相比,纳米TiO2改性混凝土 (NTC) 具有较好的解耐受性,质量损失较小,强度保持更好. 虽然NTC可以减轻损伤,但它的折断性好处有限.
科学领域:
- 材料科学
- 土木工程
- 纳米技术
背景情况:
- 混凝土的耐用性对于基础设施的寿命至关重要.
- 融周期对混凝土结构构成重大威胁,导致其退化.
- 纳米材料有助于增强混凝土的性能.
研究的目的:
- 评估纳米TiO2改性混凝土 (NTC) 与普通混凝土的抗性.
- 分析融周期对混凝土质量损失,超声速,压力强度和断裂性的影响.
- 使用粒子流代码 (PFC2D) 模拟来验证实验结果.
主要方法:
- 在重复的冷解周期下对普通和NTC进行实验测试.
- 测量质量损失,超声速,压力强度和断裂性.
- 用于内部损伤分析的二维粒子流代码 (PFC2D) 模拟.
主要成果:
- 与普通混凝土相比,NTC在100个融周期后显著减少质量损失 (52.17%) 和超声速增加 (37.31%).
- 与普通混凝土相比,NTC 的压力降低程度较小 (13.37 MPa 的降低).
- 这两种材料的破裂性大大降低,而NTC的破裂度降低了80.9%,而普通混凝土则降低了89.7%.
结论:
- 纳米TiO2的结合有效地提高了混凝土对融损坏的抵抗力,特别是在保持压力强度方面.
- 虽然NTC减轻了整体降解,但其在严重的融条件下保持断裂承载能力需要进一步调查.
- PFC2D模拟准确地反映了实验结果,证实了它们在混凝土中模拟融降解的实用性.
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