在持续的压力负荷下,回收聚合混凝土的盐损伤演变和运输特性
Zihao Yu1, Guanghui Gao1, Jiuwen Bao1
1School of Civil Engineering, Qingdao University of Technology, Qingdao 266033, PR China.
The Science of the total environment
|June 6, 2024
概括
经过机械负荷和冷解周期的再生聚合混凝土 (RAC) 在0.3fc压力下显示出更好的抗性. 微结构分析揭示了影响伤害和相对动态弹性模量 (RDEM) 的毛孔性变化.
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
- 环境工程 环境工程
背景情况:
- 在寒冷地区,回收聚合混凝土 (RAC) 的性能是复杂的,因为它包含了回收粗聚合物 (RCA).
- 机械负荷和环境压力因素 (冷-解,化物) 的组合进一步复杂化了RAC的损伤机制.
研究的目的:
- 为了研究单轴压缩负荷,结解周期和化物透对RAC性能的影响.
- 分析不同的RCA更换比率如何影响伤行为.
- 开发一个损伤模型来量化RAC相对动态弹性模量 (RDEM) 上的组合应力效应.
主要方法:
- 在0.1fc,0.3fc和0.5fc的单轴压缩负荷.
- 暴露于冷解周期和化物透.
- 评估相对动态弹性模量 (RDEM),质量传输和微观结构使用X射线计算机断层扫描 (X-CT),入孔测量 (MIP) 和扫描电子显微镜 (SEM).
主要成果:
- 在0.3fc下加载的标本显示出增强的抗性,水吸收和含量较低.
- 增加的压力应力最初减少,然后增加RAC的微结构密度和多孔性.
- RAC的RDEM随着孔的球形性减少而下降,在0.5fc时球形性增加了60.4%,导致RDEM下降了17.72%.
- 冰损坏的RAC的初始吸收性与孔隙性呈现出线性相关性.
结论:
- 机械负荷显著影响RAC的伤和质量运输特性.
- 微观结构特征,特别是孔隙结构,是RAC在环境和机械应力下耐用性的关键决定因素.
- 该研究通过阐明RAC在复杂的服务条件下的行为,为在寒冷环境中利用RCA提供了理论基础.
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