自压缩混凝土的耐用性 用岩沙和回收粗聚合物制成的自压缩混凝土
Hao Yan1, Qing Liu2, Fengxia Han2
1College of Civil Engineering and Architecture, Xinjiang University, Urumqi 830017, China.
Materials (Basel, Switzerland)
|October 14, 2023
概括
大气流沙 (AS) 和回收粗聚合物 (RCA) 在冷解周期下提高了混凝土的性能. 最佳使用AS和RCA可提高耐用性,并提供可持续的建筑解决方案.
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
- 环境科学 环境科学
背景情况:
- 建筑业面临着天然沙子和石资源的枯竭.
- 岩沙 (AS) 和回收粗聚合物 (RCA) 为混凝土改造提供了可持续的替代方案.
- 了解结合AS和RCA的混凝土的融损伤对于其实际应用至关重要.
研究的目的:
- 调查用AS和RCA (ARSCC) 修改的自压缩混凝土的解阻力.
- 在冷解条件下分析ARSCC的降解机制.
- 开发一个ARSCC融损伤的预测模型.
主要方法:
- 准备12个ARSCC样本组,具有不同的AS (0-60%) 和RCA (0-50%) 替代率.
- 进行冷解周期实验,并通过质量损失率 (Wn) 和相对动态弹性模量 (Pn) 来评估降解.
- 微观分析 (SEM) 和响应表面方法用于损害变量确定和使用韦布尔分布和灰色理论的模型开发.
主要成果:
- 弹性相对动态模量 (Pn) 有效地表明了ARSCC在冷解期间的内部结构演变.
- 加入AS有助于填补RCA中的有害毛孔,显著抑制结解损伤.
- 对AS和RCA的最佳替代率分别为20-40%和25-50%.
结论:
- 该研究成功开发了ARSCC的冷解损伤模型,并通过实验数据验证.
- 开发的模型显示了在结解周期下预测ARSCC损伤的潜力.
- 这些发现支持使用AS和RCA作为冷环境中耐用混凝土的环保材料.
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