摘要
文章为研究不同加载模式下钢结构局部焊接区域的力学性能退化规律,首先对5组Q235B对接焊缝连接钢板试件开展总周期长达12月的盐雾环境暴露腐蚀试验,采用三维形貌扫描技术对不同龄期、不同焊接区域锈蚀特征进行分析,随后对不同锈蚀程度焊接钢板试件开展单调及循环加载试验和数值模拟分析,详细研究锈蚀损伤及荷载类型等因素对焊接钢板受力行为、性能和失效模式的影响。研究结果表明:①局部点蚀深度随锈蚀深度的增大呈阶梯型增长趋势,受焊接过程影响,热影响区锈蚀速率略高于焊缝及母材区;②单调及循环荷载作用下锈蚀焊接钢板均在热影响区发生断裂,当锈蚀较为严重时,焊接钢板的断口形貌由韧窝断裂向剪切断裂转变;③循环荷载作用下,锈蚀焊接钢板强度、变形和耗能能力均呈现更显著的劣化现象,但锈蚀损伤对循环硬化效应的影响有限;④基于锈蚀特征参数建立的循环本构模型和等效循环延性断裂模型可准确模拟锈蚀损伤对焊接钢板受力性能及断裂行为的影响。
In order to study the degradation laws of mechanical properties in the local welding area of the steel structure under different loading modes,five groups of Q235B butt⁃welded steel plate specimens were exposed to a salt spray environment for a total period of 12 months,and the corrosion characteristics corresponding to different ages and different welding areas were analyzed by three⁃dimensional morphology scanning technology.Furthermore,monotonic and cyclic loading tests and numerical simulation analysis were carried out on welded steel plate specimens with different corrosion degrees,and the effects of corrosion damage and load type on the mechanical behavior,performance,and failure mode of welded steel plate were analyzed.The results showed that:①The local pitting depth increased step by step with the total corrosion depth.Due to the effects of the welding process,the corrosion rate in the heat⁃affected zone was slightly higher than that in the weld and base metal zone;②Under monotonic and cyclic loading,the corroded welded steel plate failed in the heat⁃affected zone.With the development of corrosion,the fracture morphology of the welded steel plate transformed from ductile fracture to shear fracture;③Under cyclic loading,the strength,deformation and energy dissipation capacity of corroded welded steel plates showed more significant deterioration,but the effect of corrosion damage on the cyclic hardening effect was limited;④The cyclic constitutive model and equivalent cyclic ductile fracture model based on the corrosion characteristic parameters were able to accurately simulate the effect of corrosion damage on the mechanical properties and fracture behavior of welded steel plate.
作者
王皓
徐善华
Wang Hao;Xu Shanhua(Central Research Institute Building and Construction Co.,Ltd.,MCC Group,Beijing 100088,China;Xi’an University of Architecture and Technology,Xi’an 710055,China)
出处
《土木工程学报》
EI
CSCD
北大核心
2022年第11期10-25,共16页
China Civil Engineering Journal
基金
国家自然科学基金(52008414,52178165)。
关键词
锈蚀损伤
焊接钢板
受力性能
失效模式
本构关系
等效断裂模型
corrosion damage
welded steel plate
mechanical performance
failure mode
constitutive relation
equivalent fracture model
