在循环和终极柔性负荷下,改装为超高性能混凝土的钢筋混凝土T梁的实验研究
Abbas Khodayari1, Sheharyar Rehmat2, Alireza Valikhani3
1Department of Civil and Environmental Engineering, Florida International University, Miami, FL 33174, USA.
Materials (Basel, Switzerland)
|December 23, 2023
概括
超高性能混凝土 (UHPC) 为结构缺陷的桥梁提供了持久的改造解决方案. 这项研究证明了UHPC的存在.
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
背景情况:
- 由于结构缺陷,桥梁需要改造.
- 像混凝土和钢克这样的传统方法在恶劣的环境中面临耐用性问题.
- 超高性能混凝土 (UHPC) 具有优越的材料性能,用于结构改造.
研究的目的:
- 评估修复受损钢筋混凝土 (RC) T 梁的可行性和结构性能,使用外部 UHPC 包裹.
- 研究UHPC在提高现有桥梁结构的耐用性和承载能力方面的有效性.
主要方法:
- 一个大规模的RC T-beam被人工损坏,然后再装配一个外部的UHPC层.
- 表面准备包括喷砂,以暴露强化,模拟恶化.
- 改装后的梁经历了广泛的循环负荷 (1576万个循环),随后进行了最终的柔性测试.
主要成果:
- 在循环测试期间,RC-UHPC复合梁没有出现明显的裂,但经历了12.22%的刚性降解.
- 最终的曲测试显示,RC和UHPC之间没有滑动,具有典型的曲失效模式.
- 越来越多的网络增强将故障模式转移到更分布式的破裂.
结论:
- 外部UHPC外套是一种可行的方法,用于改造受损的RC结构.
- 超高压电压改装增强了结构完整性和耐用性,尽管刚性降解需要进一步研究.
- 在UHPC层内优化增强可以控制故障模式以提高性能.
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