盐溶液侵蚀对回收精细聚合物ECC的机械性能和微孔结构的影响
Yuanhang Xiang1, Fengxia Han1,2, Qing Liu1,2
1School of Architectural Engineering, Xinjiang University, Urumqi 830046, China.
Materials (Basel, Switzerland)
|June 19, 2024
概括
使用回收精细聚合物 (RA) 的工程混凝土复合材料 (ECC) 显示了最初的机械性能改善,随后在硫酸盐和蚀下降解. 侵蚀产品填充和破坏毛孔,最终降低RAECC的强度.
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.
- 环境工程 环境工程
背景情况:
- 工程水泥复合材料 (ECC) 提供增强的柔性和裂控制.
- 在建筑材料中使用回收精细聚合物 (RA) 解决了可持续性问题.
- 硫酸盐和化物诱导的降解对混凝土的耐用性构成重大威胁.
研究的目的:
- 研究硫酸盐和硫酸盐酸盐干湿循环侵蚀对RA (RAECC) 的ECC机械性能的影响.
- 分析侵蚀对RAECC微观孔隙结构的影响.
- 在发生重大材料降解之前,确定最佳的干湿周期数量.
主要方法:
- 进行了单轴拉伸和四点曲试验,以评估机械性能.
- 使用共振频率比来监测侵蚀期间的样本完整性.
- 使用X射线计算机断层扫描 (X-CT) 来进行微观孔隙结构分析.
主要成果:
- 在腐蚀性溶液下,RAECC的机械性能 (拉力和强度) 最初增加,然后下降.
- 在5%的Na2SO4溶液中观察到最严重的侵蚀.
- 用共振频率比表示的样品完整性,在5%Na2SO4.4中经过15个干湿周期后达到峰值.
- 毛孔空间最初减少,然后增加,毛孔数量增加和球形性差.
结论:
- 硫酸盐和化物侵蚀最初填充毛孔,可能改善RAECC特性,但最终导致毛孔破坏和机械性能下降.
- 5%的Na2SO4溶液表现出最具攻击性的侵蚀行为.
- 了解孔隙结构演变对于预测RAECC在循环环境暴露下的耐用性至关重要.
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