在实验和数值测试中,在静态负载下喷涂在梁表面的开发硬型聚氨酸的增强效应评估
Tae-Hee Lee1, Jang-Ho Jay Kim1
1School of Civil and Environmental Engineering, Yonsei University, 50, Yonsei-ro, Seodaemun-gu, Seoul 03722, Republic of Korea.
Materials (Basel, Switzerland)
|November 9, 2024
概括
刚性型聚氨 (STPU) 有效地改造了老化的结构,提高了它们的刚性和承载能力. 这种创新材料提高了结构性能,并防止了脆性故障,为基础设施维护提供了快速和成本效益的解决方案.
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
- 结构工程 结构工程
背景情况:
- 陈旧的结构 (超过30年) 呈现出显著的结构性恶化,需要快速和简单的维护解决方案.
- 一般聚氨 (PU) 提供易于应用,但缺乏用于有效改造体和混凝土所需的刚性.
- 现有的老旧结构的改造方法往往耗时且昂贵.
研究的目的:
- 评估硬型聚尿素 (STPU) 在静态负荷下对立体构件的增强效应.
- 为了评估由STPU改装的梁的弹性负载能力的提高.
- 为了确定最有效的STPU应用方法用于体结构增强.
主要方法:
- 通过化学修饰一般聚氨酸以增强度来开发硬型聚氨酸 (STPU).
- 用三种不同的STPU应用方法对修梁进行实验测试.
- 用实验数据进行模拟的有限元法 (FEM) 模型的校准.
主要成果:
- STPU显著提高了造梁的曲负载能力.
- 应用STPU将脆性故障模式转化为柔性行为,改善整体结构性能.
- 这项研究确定了最佳的STPU应用技术,用于体增强.
结论:
- STPU是一种可行的和有效的材料,用于改造老化的体结构.
- STPU提高了体元素的结构完整性和抗震性能.
- 经过验证的FEM模型为未来的参数研究和改装成的优化结构设计提供了基础.
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