从记录跨度预应力混凝土桥梁的时间依赖偏移中吸取教训.
Teng Tong1,2, Chenyi Zhao2, Shiyu Wu3,4
1Key Laboratory of Concrete and Prestressed Concrete Structures of Ministry of Education, School of Civil Engineering, Southeast University, Nanjing, 211189, People's Republic of China.
Scientific reports
|November 11, 2025
概括
分段建造的预应力混凝土 (PC) 桥梁往往会遭受过度屈曲和破裂. 这项研究引入了一个新的数值框架,以改善这些创纪录的PC桥梁的设计和长期耐用性.
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:
- 超过60%的创纪录跨度分段建造的预应力混凝土 (PC) 桥梁面临过度屈曲,裂和低估的预应力损失等问题.
- 目前的设计限制限制最大跨度容量约为350米,由于不可靠的方法和软件限制.
研究的目的:
- 开发和验证一个全面的数值框架,用于分析细分构建的PC桥的时间依赖行为.
- 为了研究非线性爬行,裂和增强行为对桥梁性能的影响.
主要方法:
- 开发了一个多领域,时间依赖的数值框架,集成混凝土裂纹,非线性爬行,收缩,强化行为和前应力肌放松.
- 该框架在Abaqus/Standard中实现,使用用户定义的子程序进行高保真3D模拟.
- 在三个记录跨度的PC桥上进行了验证.
主要成果:
- 发现非线性爬行和混凝土裂显著恶化了折曲,这是以前研究中经常被低估的因素.
- 向下曲的悬臂肌对于抵消螺纹条在预应力时的可变有效性至关重要.
- 达到适当的最终应力状态对于控制这些结构的长期屈曲至关重要.
结论:
- 开发的数值框架为分段构建的PC桥梁提供了高保真度的模拟.
- 结果为提高设计策略和创纪录的PC桥梁的长期耐用性提供了必要的见解.
- 精确的时间依赖现象建模是缓解常见性能问题的关键.
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