摘要
以钢管-焊接空心球节点为研究对象,基于数值模拟、静力和常幅疲劳试验等,针对9个大尺寸节点试件进行试验和理论研究。结果表明:静力试验和数值模拟所得节点应力分布规律基本一致,试件热点应力位于钢管-焊接空心球节点焊缝焊趾管面处,并建立其相应的热点应力集中系数计算公式。对节点热点应力集中系数的不同影响因素进行探讨并排序,按大小排序的结果为:管外径>管壁厚度>球径>球壁厚。节点试件常幅疲劳破坏均位于钢管-焊接空心球/板连接焊缝焊趾管面处,其疲劳破坏断口面与试件加荷方向垂直。根据常幅疲劳试验结果,建立基于高应力幅作用下节点试件常幅疲劳S-N曲线和方程,以得到不同应力幅下该类节点的疲劳寿命。
The key to the fatigue of the grid structure was the fatigue of the nodes.In this study,the'steel pipe-welded hollow sphere'node(referred to as'tube-sphere'node)was selected as the research object.Based on numerical simulation,static and constant-amplitude fatigue test,etc.,nine specimens with large-scale node were evaluated through experimental and theoretical studies.The results showed that the stress distribution of joints obtained from static test and numerical simulation was basically the same.The hot spot stress of the test piece was located at the weld toe face of the'tube-sphere'joint weld.The corresponding calculation formula of the hot spot stress concentration coefficient was developed.The different factors of the stress concentration coefficient at the node hotspot were analyzed and discussed.The decreasing influence degree of different factors was the pipe outer diameter,pipe wall thickness,ball diameter,ball wall thickness.The fatigue failures of the specimens at the constant amplitude were located at the weld toe surface of the tube-ball/plate joint weld.The fatigue fracture surfaces were perpendicular to the loading direction of the specimens.Based on the results of the constant-fatigue test,the S-N curves and equations for the constant amplitude fatigue of the joint specimens under high stress amplitude were established to obtain the fatigue life of the joints under different stress amplitudes.
作者
贾玥
焦晋峰
雷宏刚
JIA Yue;JIAO Jinfeng;LEI Honggang(College of Architecture and Civil Engineering,Taiyuan University of Technology,Taiyuan 030024,China)
出处
《中国科技论文》
CAS
北大核心
2018年第24期2796-2803,共8页
China Sciencepaper
基金
国家自然科学基金资助项目(51578357)
山西省自然科学基金资助项目(2015011062)
山西省研究生联合培养基地人才培养资助项目(2016JD11)
