环口板加固T型圆钢管节点的应力集中系数  

Stress Concentration Factor for Circular Tubular T-joints with Collar Plate Reinforcement

作　　者：蔡艳青[1] 邵永波[1] 

机构地区：[1]烟台大学土木工程学院,山东烟台264005

出　　处：《土木工程与管理学报》2011年第2期26-31,共6页Journal of Civil Engineering and Management

基　　金：国家自然科学基金(50808153)

摘　　要：由于焊接钢管结构在焊缝处的刚度具有不连续性,因此,该部位存在很高的应力集中现象。局部高应力的存在,使节点在长期循环荷载的作用下,会产生微小的疲劳裂纹,而疲劳裂纹的扩展最终会导致整个节点的疲劳破坏。在研究管节点疲劳破坏时,主要通过热点应力幅(S-N曲线方法)确定其疲劳寿命。在计算焊缝处的热点应力幅大小时,经常用到焊缝周围的应力集中系数。本文对4个环口板加固T型圆钢管节点试件以及相应的4个未加固试件的应力集中系数进行了试验研究。通过试验测试和结果分析,得到了轴向荷载下环口板加固试件及未加固试件沿焊缝的应力集中系数分布,通过比较发现,环口板加固后的T节点试件的应力集中系数相对于未加固试件有明显减小,说明这种加固措施可以提高管节点的疲劳寿命。As the stiffness of welded steel structure at the weld is not continuous,high stress concentration exists around the weld toe.The local high gradient stresses can cause fatigue crack along the weld when the tubular joint is subjected to long-term cyclic loading.The propagation of the fatigue crack finally makes the failure of the entire joint structure.In the study of the fatigue failure of a tubular joint,hot spot stress range（S-N curve） is usually used,and stress concentration factor（SCF） is also used to determine the hot spot stress range.Experimental investigation is carried out to study the SCFs of 4 collar plate reinforced and 4 corresponding un-reinforced tubular T-joint specimens.Through analyses on the experimental results,the SCF distributions along the weld for all the specimens are obtained.It is found that the SCFs of the reinforced specimens significantly reduce compared to the un-reinforced ones.This shows that the collar plate reinforcing measurement can greatly improve the fatigue life of tubular T-joints.

关 键 词：T型圆钢管节点 环口板 应力集中系数 试验研究 

分 类 号：TU398[建筑科学—结构工程]