钢结构角焊缝抗剪疲劳性能的试验研究  

EXPERIMENTAL STUDY ON SHEAR FATIGUE BEHAVIOR OF STEEL STRUCTURE FILLET WELDS

作　　者：王元清[1] 顾浩洋 廖小伟[1] WANG Yuan-qing;GU Hao-yang;LIAO Xiao-wei(Key Laboratory of Civil Engineering Safety and Durability of China Education Ministry,Department of Civil Engineering,Tsinghua University,Beijing 100084,China)

机构地区：[1]土木工程安全与耐久教育部重点实验室,清华大学土木工程系,北京100084

出　　处：《工程力学》2018年第4期61-68,共8页Engineering Mechanics

基　　金：国家自然科学基金项目(51378289;51678339)。

摘　　要：国内外学者对钢结构的焊缝连接在名义正应力荷载条件下的疲劳性能进行了广泛的研究,但是所见文献中对焊缝在名义剪切应力下的疲劳性能研究较少。为此,以Q345B钢材制作了原状处理的侧面和正面角焊缝连接的2组板材试件,采用高频疲劳试验机进行常温剪切疲劳试验,并进行数据拟合。试验结果发现:该文试验中的2类焊接试件的疲劳试验结果具有非常大的离散性。由中国钢结构规范GB 50017—2017得到的200万次下的疲劳强度值比侧面角焊缝试验拟合曲线计算得到的值小,两者曲线吻合较好;正面角焊缝试验所得疲劳强度高于各国规范;正面角焊缝接头抗剪切疲劳强度高于侧面角焊缝接头;正面角焊缝疲劳破坏形式为贯通焊缝裂纹,侧面角焊缝为焊趾向热影响区延伸裂纹。研究结果表明:现有中国规范评价侧面和正面角焊缝剪切性能都偏于安全,但是使用规范推荐的曲线评估侧面角焊缝剪切疲劳性能较为合适。Although research on fatigue properties of welds under normal stress loading conditions was conducted widely by scholars world widly,little study on shear fatigue resistance has been done.A number of shear fatigue tests are conducted on a high frequency fatigue machine.For the tests,side fillet welded and front fillet welded specimens are used.The test results show that the discreteness of the fatigue strength is fairly great.The shear fatigue strength of Q345B longitudinal fillet welded connections under two million times of loading is greater than the corresponding strength calculated according to the GB 50017-2017 code.The two curves match well.The fatigue strength of the front fillet weld is higher than those given by the codes of many countries.The fatigue performance of the front fillet welds is better than that of the side fillet welds.The fatigue failure cracks of the front fillet weld go through the weld.Meanwhile,cracks of side fillet weld extend from the weld toe to the heat affected zone.The results show that the current Chinese standard evaluation of fillet weld shear performance is conservative,but the fatigue performance of side fillet weld is more consistent with the recommended curve.

关 键 词：钢结构 抗剪疲劳 角焊缝 S-N曲线 规范对比 

分 类 号：TU391[建筑科学—结构工程]