纳米SiO2-修改回收聚合物混凝土的爬行和收缩特性
Yingwu Zhou1, Jiahao Zhuang1, Wenwei Lin1
1Guangdong Provincial Key Laboratory of Durability for Marine Civil Engineering, Shenzhen University, Shenzhen 518060, China.
Materials (Basel, Switzerland)
|April 27, 2024
概括
与RAC相比,Nano-SiO2预浸泡改善了回收混凝土聚合物 (RCA) 的质量,在NS改性回收混凝土混凝土 (SRAC) 中减少了7%的爬行和收缩. 根据替换率,SRAC的表现会有所不同.
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.
- 混凝土技术 混凝土技术
背景情况:
- 回收混凝土聚合物 (RCA) 的性能较差,导致与天然聚合混凝土 (NAC) 相比,回收混凝土混凝土 (RAC) 的爬行和收缩增加.
- 提高RCA质量对于可持续的建筑实践和提高使用回收材料的混凝土耐用性至关重要.
研究的目的:
- 调查纳米SiO2 (NS) 预浸泡对RCA质量的影响.
- 评估NS改性循环聚合混凝土 (SRAC) 在各种天然聚合物 (NA) 替代水平上的爬行和收缩特性.
- 为了比较SRAC爬行和收缩的既定模型的预测准确度.
主要方法:
- 预浸泡RCA与2%的纳米SiO2溶液,以创建NS改性循环聚合物 (SRCA).
- 以不同的百分比 (30%,50%,70%,100%) 用SRCA取代NA以产生SRAC.
- 使用有限元法模拟爬行和收缩应变.
- 将实验结果与CEB-FIP,ACI,B3和GL2000模型的预测进行比较.
主要成果:
- 与NAC相比,SRAC的爬行和收缩变形通常增加,SRCA的替换率较高.
- 在100%的SRCA替代时,与RAC相比,爬行和收缩变形减少了7%.
- CEB-FIP和ACI模型在预测爬行和收缩应变方面表现出合理的准确性.
结论:
- 纳米SiO2预浸泡是一种有效的方法来提高RCA的质量.
- SRAC表现出受SRCA替换率影响的修改后的爬行和收缩特征.
- 已建立的预测模型,如CEB-FIP和ACI可以用于SRAC,为结构设计提供有价值的见解.
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