纽带剪切测试,以评估不同CFRP剪切强化策略,用于I形混凝土截面
Muhammad Arslan Yaqub1, Christoph Czaderski2, Stijn Matthys1
1Magnel-Vandepitte Laboratory, Department of Structural Engineering and Building Materials, Ghent University, 9052 Ghent, Belgium.
Materials (Basel, Switzerland)
|July 13, 2024
概括
使用碳纤维增强聚合物 (CFRP) 的I形混凝土梁的剪切强化具有挑战性. 将I字形转换为带入填充块和CFRP的矩形显著提高了剪切能力.
科学领域:
- 土木工程 土木工程是指土木工程.
- 结构工程 结构工程
- 材料科学 材料科学 材料科学
背景情况:
- 在桥梁和屋顶上,I形混凝土梁很常见.
- 现有的剪切强化方法,如碳纤维增强聚合物 (CFRP),面临着I型的挑战,特别是在角落过早脱.
- 这限制了CFRP在提高剪切能力方面的有效性.
研究的目的:
- 评估混凝土I段的两种不同的CFRP剪切强化策略.
- 调查填充块材料和固系统对增强性能的影响.
- 引入一种新的测试方法来评估I段的剪切强化配置.
主要方法:
- 测试了两种CFRP强化策略:在CFRP U-wrapping之前直接粘合到I形以固定,并使用填充块将I形转换为矩形.
- 研究的填充材料包括传统混凝土和空气混凝土.
- 评估了两个固定方案:螺栓钢板和CFRP尖固定.
- 为了避免大规模的梁测试,为混凝土I截面开发了一种新的测试方法.
主要成果:
- 该研究证明了新的测试方法可行性,用于比较剪切强化策略.
- 将I字形转变为带有填充块和CFRP的矩形截面证明是有效的.
- 剪切强度的增强范围为12% (没有定) 到53% (有定) 的矩形I截面.
结论:
- 将I形混凝土梁转化为相当的矩形形状是切割强化的一种可行的策略.
- 使用填充块和CFRP,特别是具有有效的 anchorage,可以显著提高剪切能力.
- 开发的测试方法提供了一种可靠的方法来评估I段的剪切强化技术.
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