在静态和冲击负荷下使用聚氨底料修复的混凝土的结合强度的评估,加上统计分析
Sadi Ibrahim Haruna1, Yasser E Ibrahim1, Ali Al-Shawafi2
1Engineering Management Department, College of Engineering, Prince Sultan University, Riyadh 11586, Saudi Arabia.
Polymers
|October 16, 2024
概括
聚氨 (PU) 能够有效地修复破碎的混凝土,达到足够的粘合强度,超过ASTM ACI 546-06标准. 虽然稍微降低了压力强度,但PU修复在受损混凝土结构的静态和冲击负载下表现出弹性.
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.
- 结构维修 结构维修
背景情况:
- 有效的混凝土修复取决于在各种应力下在接口上达到足够的粘合强度.
- 由于屈曲和拉伸应力导致的混凝土元素中的自然断裂需要强大的修复解决方案.
研究的目的:
- 为了研究用聚氨 (PU) 矩阵修复的普通混凝土 (NC) 元素的粘合特性.
- 评估在静态 (压缩,分裂) 和动态 (重量下降冲击) 负载条件下PU修复的有效性.
主要方法:
- 准备和破碎的普通混凝土 (NC) 标本 (立方体,梁,U形).
- 使用聚氨 (PU) 矩阵修复破碎的标本.
- 进行压缩,分裂和落重量冲击 (DWI) 测试以评估债券强度.
主要成果:
- 该PU矩阵证明了NC基板的有效修复,实现了足够的结合强度,超过ASTM ACI 546-06最低值.
- 经过修复的标本显示压力强度下降 (47.3%和31.5%),分别沿着和平行加载到接口时.
- 下降重量冲击测试表明,参考和修复的标本之间具有可比的裂纹阻力,参考梁具有略高的负载能力.
结论:
- 聚氨 (PU) 是修复受损混凝土结构的有希望的粘合剂,在静态和冲击负荷下提供足够的界面粘合强度.
- 虽然压力强度降低了,但PU修复方法符合损坏的混凝土元素的康复标准.
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