Investigation on the Effect of Initial Welding Imperfection on Fatigue strength of Tubular Member by FEM

2nd International Conference on Sustainable Development in Civil, Urban and Transportation Engineering

地球科学;运输工程;经济学

Chang, Kyong-Ho^1 ; Shin, Wang Sub^1 ; Van Vuong, Do Nguyen^2 ; Lee, Chin Hyeong^3

Department of Civil and Environmental and Plant Engineering, Chung-Ang University, Huksuk-ro, 84, Dongjak-gu, Seoul

06974, Korea, Republic of^1

Department of Civil Engineering, Ton Duc Thang University, 19 Nguyen Huu Tho, District 7, Ho Chi Minh City, Viet Nam^2

Graduate School of Construction Engineering, Chung-Ang University, Huksuk-ro, 84, Dongjak-ku, Seoul

06974, Korea, Republic of^3

关键词: Heat-conduction analysis;    Initial imperfection;    Off shore platforms;    Repeated loading;    Steel tubular structures;    Thermal elastic-plastic analysis;    Tubular structures;    Welding deformations;   

Others  :  https://iopscience.iop.org/article/10.1088/1755-1315/143/1/012031/pdf
DOI  :  10.1088/1755-1315/143/1/012031

来源: IOP

【 摘 要 】

Steel tube structure is used for steel structure such as offshore platform, bridges and so on. Also, all circular members of tubular structures are mainly connected by welding. When the steel tubular structures are subjected to repeated loading, not only the load carrying capacity is reduced but also fatigue cracks may develop at the joint part of steel tubular members which are connected by welding. Carrying out welding, welding initial imperfection such as welding deformation and residual stress are inevitably generated at weld part. It was well known that the effect of welding residual and welding deformation on fatigue strength. However, It's not clear which affects fatigue strength more. However, it's difficult to clear the effect on fatigue strength by experiment. To clarify these effect, fatigue analysis was carried out by FEM which is based on continuum damage mechanics. On the other hand, coupled three-dimensional non-steady heat conduction analysis, and the thermal elastic-plastic analysis was carried out to reproduce the initial weld state of tubular member. From the result, not only the fatigue strength of welded tubular member but also the fatigue life could be found by FEM fatigue analysis.