Multiaxial Fatigue Assessment of Pile Leg Joint under Complex Stress State

Abstract

Abstract:

A new multiaxial fatigue criterion is introduced. In combination with the hot spot stress method, it is used to estimate the fatigue life of about 250 test specimens published in international open literature, through which the accuracy of the new method is verified. Finally we use the new method to do a successful fatigue life assessment of the pile leg joint. This research provides an available reference to improve the accuracy of the fatigue life prediction of pile leg joint.

Key words: jack-up platform, tubular joint, stress concentration, multiaxial fatigue

CLC Number:

U661.43

Ying-fang LIU, Hong-feng LIU, Fu-hong JIANG, Li-zhong SAN, Yan-feng WANG, Wan-xiong XU. Multiaxial Fatigue Assessment of Pile Leg Joint under Complex Stress State[J]. Ocean Engineering Equipment and Technology, 2015, 2(2): 75-79.

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编号	参考文献	材料	屈服极限 /MPa	载荷形式
a	[11]	StE 460	520	B-T
b	[12]	SAE 1050	655	Te
c	[13]	Fe 52钢	355	B-T
d	[14--15]	StE 460	520	B-T
e	[16]	A519-A36	552	B-T
f	[17]	BS4360 Gr. 50E	415	Te-T

工况	载荷	名义弯曲		名义拉伸		相位差 φ/(°)	正应力范围 /MPa	剪应力范围 /MPa	预测寿命 N_f,est/次
工况	载荷	应力幅 B_a/MPa	平均应力 B_m/MPa	应力幅 Te_a/MPa	平均应力 Te_m/MPa	相位差 φ/(°)	正应力范围 /MPa	剪应力范围 /MPa	预测寿命 N_f,est/次
1	纯弯曲	100	0	0	0	0	218.14	218.33	1.08×10⁵
2	纯拉伸	0	0	100	0	0	126.11	126.12	5.61×10⁵
3	同相	100	0	100	0	0	344.46	344.44	2.75×10⁴
4	非比例	100	0	100	0	90	251.93	252.14	7.03×10⁴
5	纯弯曲	100	100	0	0	0	218.14	218.33	5.54×10⁴
6	纯拉伸	0	0	100	100	0	126.11	126.12	2.87×10⁵
7	同相	100	100	100	100	0	344.46	344.44	1.41×10⁴
8	非比例	100	100	100	100	90	251.93	252.14	3.60×10⁴