Research on stress concentration factor of tube joints under pure bending and torsion loading
|
摘要
For fatigue strength design and evaluation as well as for multiaxial fatigue tests analysis of welded structures, the stress concentration factor(SCF) at the weld must be known. In the present study, two common models of multiaxial fatigue tests, tube-plate(TP) model and tube-tube(TT) model are selected as the research objects. SCFs of the two models with various geometric parameters under pure bending and pure torsion loading have been investigated by conducting a series of three-dimensional(3 D) finite element models based on linear elasticity theory. The effect of weld width(w), plate thickness(t), weld toe notch radius(r), and reinforcement angle(θ) on SCF is assessed. The quadratic parametric equations based on t/r are proposed to predict SCFs of the two models, which reveal satisfactory accuracy.
For fatigue strength design and evaluation as well as for multiaxial fatigue tests analysis of welded structures, the stress concentration factor(SCF) at the weld must be known. In the present study, two common models of multiaxial fatigue tests, tube-plate(TP) model and tube-tube(TT) model are selected as the research objects. SCFs of the two models with various geometric parameters under pure bending and pure torsion loading have been investigated by conducting a series of three-dimensional(3 D) finite element models based on linear elasticity theory. The effect of weld width(w), plate thickness(t), weld toe notch radius(r), and reinforcement angle(θ) on SCF is assessed. The quadratic parametric equations based on t/r are proposed to predict SCFs of the two models, which reveal satisfactory accuracy.
For fatigue strength design and evaluation as well as for multiaxial fatigue tests analysis of welded structures, the stress concentration factor(SCF) at the weld must be known. In the present study, two common models of multiaxial fatigue tests, tube-plate(TP) model and tube-tube(TT) model are selected as the research objects. SCFs of the two models with various geometric parameters under pure bending and pure torsion loading have been investigated by conducting a series of three-dimensional(3 D) finite element models based on linear elasticity theory. The effect of weld width(w), plate thickness(t), weld toe notch radius(r), and reinforcement angle(θ) on SCF is assessed. The quadratic parametric equations based on t/r are proposed to predict SCFs of the two models, which reveal satisfactory accuracy.
引文
[1] Saini D S,Karmakar D,Ray-Chaudhuri S.A review of stress concentration factors in tubular and non-tubular joints for design of offshore installations.Journal of Ocean Engineering and Science,2016,1(3):186-202.
[2] Shao Y B.Analysis of stress concentration factor of welded tubular K-joints subjected to axial loads.Journal of Ship Mechanics,2010(4):399-408.(in Chinese)
[3] Lie S T,Vipin S P,Li T.New reduction factor for cracked square hollow section T-joints under axial loading.Journal of Constructional Steel Research,2015,112:221-227.
[4] Li T,Lie S T,Shao Y B.Fatigue and fracture strength of a multi-planar circular hollow section TT-joint.Journal of Constructional Steel Research,2017,129:101-110.
[5] Yuan K L,Jiang Y Y,Yang H T,et al.A probability distribution model for SCFs in multi-planar circular hollow section DT-joints subjected to axial loading.Journal of Ship Mechanics,2018(6):758-770.
[6] Ahmadi H,Lotfollahi-Yaghin M A,Aminfar M H.Stress concentration factors at saddle and crown positions on the central brace of two-planar welded CHS DKT-connections.Journal of Marine Science and Application,2012,11(1):83-97.
[7] Sonsino C M.Multiaxial fatigue of welded joints under in- and out-of-phase local strains and stresses.International Journal of Fatigue,1995,95(17):55-70.
[8] Yousefi F,Witt M,Zenner H.Fatigue strength of welded joints under multiaxial loading:experiments and calculations.Fatigue & Fracture of Engineering Materials & Structures,2010,24(5):339-355.
[9] Witt M,Zenner H.Multiaxial fatigue behaviour of welded flange-tube connections under combined loading.experiments and lifetime calculation.In:5th International conference on biaxial/multiaxial fatigue and fracture,Cracow,Poland,1997:421-434.
[10] Bertini L,Cera A,Frendo F.Experimental investigation of the fatigue resistance of pipe-to-plate welded connections under bending,torsion and mixed mode loading.International Journal of Fatigue,2014,68:178-185.
[11] Fricke W.Guideline for the fatigue assessment by notch stress analysis for welded structures.Assembly of International Institute of Welding,2008.
[2] Shao Y B.Analysis of stress concentration factor of welded tubular K-joints subjected to axial loads.Journal of Ship Mechanics,2010(4):399-408.(in Chinese)
[3] Lie S T,Vipin S P,Li T.New reduction factor for cracked square hollow section T-joints under axial loading.Journal of Constructional Steel Research,2015,112:221-227.
[4] Li T,Lie S T,Shao Y B.Fatigue and fracture strength of a multi-planar circular hollow section TT-joint.Journal of Constructional Steel Research,2017,129:101-110.
[5] Yuan K L,Jiang Y Y,Yang H T,et al.A probability distribution model for SCFs in multi-planar circular hollow section DT-joints subjected to axial loading.Journal of Ship Mechanics,2018(6):758-770.
[6] Ahmadi H,Lotfollahi-Yaghin M A,Aminfar M H.Stress concentration factors at saddle and crown positions on the central brace of two-planar welded CHS DKT-connections.Journal of Marine Science and Application,2012,11(1):83-97.
[7] Sonsino C M.Multiaxial fatigue of welded joints under in- and out-of-phase local strains and stresses.International Journal of Fatigue,1995,95(17):55-70.
[8] Yousefi F,Witt M,Zenner H.Fatigue strength of welded joints under multiaxial loading:experiments and calculations.Fatigue & Fracture of Engineering Materials & Structures,2010,24(5):339-355.
[9] Witt M,Zenner H.Multiaxial fatigue behaviour of welded flange-tube connections under combined loading.experiments and lifetime calculation.In:5th International conference on biaxial/multiaxial fatigue and fracture,Cracow,Poland,1997:421-434.
[10] Bertini L,Cera A,Frendo F.Experimental investigation of the fatigue resistance of pipe-to-plate welded connections under bending,torsion and mixed mode loading.International Journal of Fatigue,2014,68:178-185.
[11] Fricke W.Guideline for the fatigue assessment by notch stress analysis for welded structures.Assembly of International Institute of Welding,2008.