在合硫酸盐攻击和冷解条件下,PVA纤维增强混凝土的耐用性和微观结构演变
Hairong Wu1, Changhao Shen1, Chenjie Lv1
1School of Civil and Transportation Engineering, Henan University of Urban Construction, Pingdingshan 467036, China.
Materials (Basel, Switzerland)
|January 10, 2026
概括
这项研究发现,0.3%的PVA纤维混凝土对结合硫酸盐攻击和冷解周期提供了最佳的抵抗力,改善了机械性能和微观结构. 聚乙烯 (PVA) 纤维在寒冷,盐水环境中增强耐用性,损坏可以通过立方方程预测.
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
- 混凝土结构的耐用性
背景情况:
- 在寒冷,盐地区的混凝土结构面临着由于结合硫酸盐攻击和冷解周期的重大耐用性挑战.
- 在这些恶劣条件下了解材料退化对于基础设施的寿命至关重要.
研究的目的:
- 为了研究聚乙烯醇 (PVA) 纤维增强混凝土在联合硫酸盐攻击和冷解周期下的耐用性.
- 分析PVA纤维混凝土的降解规律和微观结构演变.
- 为了建立PVA纤维混凝土的盐伤害演化方程.
主要方法:
- 测试PVA纤维混凝土样品的机械性能 (压力强度,分裂抗拉强度) 和微观性能.
- 将标本置于不同数量的盐结周期 (0-150) 和不同的PVA纤维体积分数 (0-0.5%).
- 分析表面侵蚀,质量损失,相对动态弹性模量和微观结构变化.
主要成果:
- 乙烯纤维没有显著抑制表面侵蚀,随着盐结周期的增加,裂变会增加.
- 样品质量,相对动态弹性模量和压力强度最初增加,然后随着循环而下降;分裂拉伸强度持续下降.
- 0.3%的PVA纤维体积分数证明了机械强度和耐盐结性能的最佳改善,导致更密集的微结构和抑制微裂纹传播.
结论:
- 聚乙烯纤维增强混凝土在硫酸盐和冷解的联合攻击下表现出增强的耐用性,特别是在0.3%的纤维体积分数下.
- 损坏程度和盐结周期 (R2 > 0.88) 之间的已建立的立方函数关系准确地预测了混凝土的恶化.
- 这项研究为PVA纤维混凝土在寒冷,盐水环境中的降解机制和最佳纤维剂量提供了关键的见解,指导工程应用.
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