摘 要
钢结构节点在高温环境下的力学性能退化问题对建筑结构的安全性与耐久性具有重要影响，尤其是在火灾、工业高温环境等极端条件下。本研究旨在深入探讨高温对钢结构节点力学性能的影响机制，并提出有效的修复技术以恢复其承载能力。通过有限元模拟与实验验证相结合的方法，系统分析了不同温度水平、升温速率和保温时间对节点材料微观组织、残余应力分布及整体力学性能的综合影响。研究发现，高温会导致钢材屈服强度显著降低，塑性变形能力增强，同时节点连接部位因局部应力集中而出现不同程度的损伤。基于此，提出了一种基于复合材料加固与热处理修复相结合的技术方案，该方案能够有效改善节点的残余应力状态并部分恢复其初始力学性能。研究成果为高温环境下钢结构节点的设计优化与灾后修复提供了理论支持和技术指导，特别是在修复效率与经济性方面展现了显著优势，为相关工程实践提供了重要的参考价值。
关键词：钢结构节点；高温影响；力学性能退化；复合材料加固；热处理修复
ABSTRACT
The degradation of mechanical properties of steel structure joints under high-temperature conditions significantly affects the safety and durability of building structures, particularly in extreme scenarios such as fires or industrial high-temperature environments. This study aims to explore the influence mechanisms of high temperatures on the mechanical performance of steel structure joints and proposes effective repair techniques to restore their load-bearing capacity. By integrating finite element simulation with experimental validation, a systematic analysis was conducted on the comprehensive effects of different temperature levels, heating rates, and holding times on the microstructure of joint materials, residual stress distribution, and overall mechanical properties. The findings indicate that high temperatures lead to a notable reduction in the yield strength of steel, an increase in plastic deformation capability, and varying degrees of damage at connection areas due to localized stress concentration. Based on these insights, a technical solution combining composite material reinforcement with heat treatment restoration was proposed, which effectively improves the residual stress state of the joints and partially restores their initial mechanical properties. This research provides theoretical support and technical guidance for the design optimization and post-disaster repair of steel structure joints in high-temperature environments, demonstrating significant advantages in terms of repair efficiency and cost-effectiveness, thus offering valuable references for relevant engineering practices.
Keywords: Steel Structure Joint; High Temperature Effect; Mechanical Property Degradation; Composite Material Reinforcement; Thermal Treatment Repair
目 录
摘 要 I
ABSTRACT II
第1章 绪论 1
1.1 钢结构节点高温性能研究背景与意义 1
1.2 国内外研究现状分析 1
1.3 本文研究方法与技术路线 2
第2章 高温环境下钢结构节点力学性能退化机理 3
2.1 高温对钢材微观结构的影响 3
2.2 节点连接方式与高温退化关系 3
2.3 力学性能退化的数值模拟分析 4
第3章 钢结构节点高温退化实验研究 6
3.1 实验设计与测试方法 6
3.2 高温环境下的节点应力应变特性 6
3.3 不同温度条件下的退化规律分析 7
第4章 钢结构节点高温退化的修复技术研究 8
4.1 常见修复技术及其适用性分析 8
4.2 新型修复材料的开发与应用 8
4.3 修复效果评估与优化建议 9
结论 10
参考文献 11
致 谢 12
