基于超弹性- (NiTi) 的智能合金,用于提高混凝土结构的性能
Mohammad J Alshannag1, Ali S Alqarni1, Mahmoud M Higazey1
1Department of Civil Engineering, King Saud University, Riyadh 11421, Saudi Arabia.
Materials (Basel, Switzerland)
|June 28, 2023
概括
形状记忆合金 (SMA) 为智能结构系统提供独特的特性,增强混凝土结构. 本综述强调了SMA在民用基础设施中的应用最近的进展和未来的机会.
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.
- 结构工程 结构工程
背景情况:
- 智能材料,特别是超弹性- (NiTi) 形状记忆合金 (SMA),对于适应性结构系统越来越重要.
- SMAs具有显著的特性,如形状恢复,高强度,耐用性和耐疲劳性,使其对建筑具有吸引力.
- 现有的文献缺乏对建筑行业最近的SMA应用的全面审查,包括预应力混凝土梁和抗震强化.
研究的目的:
- 审查过去二十年来在钢筋混凝土结构中应用SMA的最新进展.
- 确定有关在具有挑战性的环境 (腐蚀性,高温,火灾) 中SMA性能的研究差距.
- 讨论SMA在具体结构中采用的障碍,例如制造成本和知识转移.
主要方法:
- 文献综述侧重于SMA在钢筋混凝土结构中的应用.
- 分析最近的研究趋势和发现.
- 确定挑战和未来的研究方向.
主要成果:
- 在预应力混凝土梁,连接的抗震强化和纤维增强混凝土方面,SMAs显示出巨大的潜力.
- 关于SMA在腐蚀性环境,高温和火灾条件下的行为存在有限的研究.
- 高昂的制造成本和研究与实际实施之间的差距阻碍了SMA的广泛使用.
结论:
- 最近的进展表明SMAs在增强混凝土结构中的价值.
- 需要进一步研究SMA在极端条件下的性能以及成本效益的制造.
- 解决实际实施挑战对于扩大民用基础设施中SMA使用至关重要.
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