基于主 S-N 曲线法的板边焊接接头疲劳评估

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中图分类号：TG407；TB115.1 文献标志码：B

Fatigue evaluation of plate edge welded joints based on master S-N curve method

XU Jixin'，DOU Fei2，GUI Zhiyuan2，LI Mingjun2，NIE Chunge2

（1.CRRC.Dalian Co.，Ltd，Dalian 116022，Liaoning，China； 2.Schoolof Locomotive&Roling Stock Engineering，Dalian Jiaotong University，Dalian 116028，Liaoning，China）

Abstract： The conventional calculation process based on the master S ？ N curve has the problem that it is difficult to calculate the fatigue control stress when evaluating the welded joints at the plate edge，and three possible calculation schemes are proposed and compared and analyzed. Scheme I calculates the structural stress of the weld toe by defining the virtual weld wire，butthe stress value is very sensitive to the mesh size due to the excessive stress gradient in the weld toe area. The calculated results of schemes I and II are not sensitive to mesh，and at the same time，they are in good agreement with the fatigue test data，which proves the applicability. Based on schemes II and ，the fatigue cracking problem of the plate side joint of a certain type of locomotive chassis is analyzed.The results show that scheme II only uses the grid in the range of 2 times the plate thickness near the weld toe for calculation，which is more suitable for engineering structures with complex geometric features and stress states.

Key words： plate edge welded joints； fatigue life；structural stress；master S N curve；finite element

0引言

焊接接头往往是焊接结构中的薄弱位置，对焊接接头进行疲劳评估是结构设计的关键环节之_[1-2]。（剩余6030字）