Stress intensity factor for a tubular T-joint with grouted chord
Stress intensity factor for a tubular T-joint with grouted chord
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DOI：
10.1016/j.engstruct.2011.10.014
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发表时间：
2012-02
影响因子：
5.5
通讯作者：
Wei Shen;Yoo Sang Choo
中科院分区：
文献类型：
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作者：
Wei Shen;Yoo Sang Choo
通过在弦杆中填充水泥浆，可以降低焊接管节点的热点应力集中系数（SCF），从而提高灌浆节点的疲劳强度。然而，在已发表的文献中，灌浆管节点的疲劳试验结果不一致，这不能用热点应力法来证明。为了更好地了解灌浆相贯节点的疲劳性能，对已报道的T型焊接相贯节点和弦杆灌浆相贯节点的疲劳试验进行了全面的断裂力学研究。先用数值方法确定两种节点的应力强度因子，然后用经验方法确定。应力强度因子的结果被发现是一致的，并在协议的疲劳试验结果。弦杆中填充灌浆的存在被发现可以减小SCF，并降低弯曲度（DOB）。对于存在焊趾疲劳裂纹的管节点，较低DOB的热点应力对应较大的裂纹驱动力，其破坏性大于较高DOB的热点应力。因此，灌浆管节点的疲劳评估，它是必要的，包括DOB的影响，这是被忽略的热点应力S-N方法推荐在一些现行的设计规范。
The hot spot stress concentration factors (SCFs) for an as-welded tubular joint can be reduced by infilling the chord member with cementious grout, with associated improved fatigue strength for the grouted joint. However, inconsistent fatigue test results of grouted tubular joints are found in the published literature, which cannot be justified by hot spot stress approach. In order to obtain a better understanding for the fatigue performance of grouted tubular joints, a comprehensive fracture mechanics study is carried out for the reported fatigue test on as-welded tubular T-joint and another joint with grouted chord. The stress intensity factors (SIFs) of the two joints are determined by numerical method and then by empirical method. The SIF results are found to be consistent and in agreement of the fatigue test results. The presence of infilled grout in the chord is found to reduce the SCF, and lower the degree of bending (DOB). For tubular joints with weld toe fatigue cracking, the hot spot stress with lower DOB is associated with larger crack driving force and is more damaging than that with higher DOB. Hence, for fatigue assessment of grouted tubular joints it is essential to include the effect of DOB, which is ignored in hot spot stress S–N approach recommended in some current design codes.