焊接节点构造细节的低周疲劳试验研究  

Experimental study on low cycle fatigue for structural details of welded joints

作　　者：黄丽珍[1,2,3] 瞿伟廉[1,2] 

机构地区：[1]武汉理工大学土木工程与建筑学院,湖北武汉430070 [2]武汉理工大学道路桥梁与结构工程湖北省重点实验室,湖北武汉430070 [3]湖北工程学院土木工程学院,湖北孝感432000

出　　处：《华中科技大学学报（自然科学版）》2016年第10期36-40,共5页Journal of Huazhong University of Science and Technology(Natural Science Edition)

基　　金：国家自然科学基金重点资助项目(51438002);国家自然科学基金面上资助项目(51378409);国家自然科学基金青年基金资助项目(51308430)

摘　　要：为了研究Q235低碳素钢平板对接焊接试件以及十字型承载V型坡口焊接试件的低周疲劳行为,采用等幅应变控制法对24个试件在不同塑性应变幅下的超低周疲劳性能进行了测试,拟合得到了两类焊接构造细节试件的疲劳寿命S-N曲线,并将测试结果与国际焊接协会发布的疲劳设计规程中同类焊接构造细节的S-N曲线进行对比.结果表明:平板对接焊接试件与十字型承载V型坡口焊接试件的裂纹起源不相同;在超低周疲劳范围内,两类焊接材料的损伤破坏主要包括材料延性损伤和循环疲劳损伤,比国际焊接协会中相同疲劳构造细节的高周疲劳寿命S-N曲线预期的疲劳强度更低,表现出更低的疲劳寿命.Low cycle fatigue tests were carried out to examine the fatigue behavior of the plate butt weld specimens and cruciform load-carrying groove weld specimens. Fatigue tests were performed on 24 low carbon steel specimens under different constant cycle strains in the plastic range. The fatigue test results were presented, and the fitting S-N curve of those two types of welded structural details could be obtained. The fatigue curves of the same welded structural details in fatigue recommendation released by International Institute of Welding were adopted to correlate the fatigue strength of those two structural details. The results demonstrate that the crack initiation location of plate butt weld specimens is not the same as that of cruciform load-carrying groove weld specimens, the cumulative damage of the two types involves ductile damage besides cyclic fatigue damage in extremely low cycle fatigue field, and the fatigue strength of each types was lower than expected high cycle fatigue S-N curves provided by IIW, showing shorter fatigue life.

关 键 词：钢结构 焊接构造细节 疲劳 损伤 低周疲劳试验 

分 类 号：TG111.8[金属学及工艺—物理冶金] TU317.1[金属学及工艺—金属学]