腐蚀环境中Q420qD钢十字接头的疲劳性能试验与数值研究  

Experimental and Numerical Study on Fatigue Performance of Q420qD Steel Cross Joint in Corrosive Environment

作　　者：程海根[1,2] 胡聪 CHENG Hai-gen;HU Cong(School of Civil Engineering and Architecture,East China Jiaotong University,Nanchang 330013,China;National Experimental Teaching Demonstration Center of Civil Engineering,East China Jiaotong University,Nanchang 330013,China)

机构地区：[1]华东交通大学土木建筑学院,江西南昌330013 [2]华东交通大学土木工程国家实验教学示范中心,江西南昌330013

出　　处：《材料保护》2021年第12期5-12,18,共9页Materials Protection

基　　金：国家自然科学基金项目(51368018,51968024)资助。

摘　　要：钢结构疲劳破坏是交变荷载长期作用下的结果,严重影响结构安全,尤其是腐蚀介质的存在,理论上就更加难以准确估计其破坏时间。采用试验和数值模拟方法,研究了腐蚀环境中Q420qD钢十字接头的疲劳性能。同时,基于S-N曲线法预测了十字接头的疲劳强度,并与相关规范进行对比分析。结果表明:角焊缝焊趾边缘位置含8个腐蚀坑的数值仿真结果与疲劳试验结果吻合度较高,其结果拟合S-N曲线可以作为处于腐蚀环境中10 a的十字接头疲劳寿命预估曲线;GJB 119规范设计曲线能够较好地预估疲劳寿命高于10万次循环的十字接头疲劳寿命,且安全储备较高。Fatigue failure of steel structure is the result of long-term alternating load,which seriously affects the safety of structure,especially under the existence of corrosive medium,and so it becomes more difficult to estimate the failure time in theory accurately.In this work,the fatigue property of Q420qD steel cross joint in corrosive environment was studied by means of experimental and numerical simulation.Meantime,the fatigue strength of the cross joint was predicted based on S-N curve method and further compared with relevant specifications.Results showed that the numerical simulation results with 8 corrosion pits at the edge of fillet weld toe were in good agreement with the fatigue test results,and the fitting S-N curve of the results could be used as the fatigue life prediction curve of the cross joint in the corrosion environment for 10 a.Moreover,the GJB 119 code design curve could better predict the fatigue life of the cross joint with a fatigue life of more than 100,000 cycles,and the safety reserve was relatively higher.

关 键 词：腐蚀环境 Q420qD钢 十字接头 疲劳性能 S-N曲线法 

分 类 号：TG174.3[金属学及工艺—金属表面处理]