摘要
依据铁路钢桥整体节点处次应力的形成和分布状态,设计次应力疲劳试件。利用双轴疲劳试验研究次应力对疲劳寿命的影响,同时进行有限元法对比分析。试验和理论分析结果表明,叠加次应力后的疲劳起裂寿命明显短于没有叠加次应力的疲劳起裂寿命,说明次应力对疲劳强度的影响不能被忽略。计算分析还发现,将次应力与轴向应力等同进行疲劳检算不恰当,将次应力全部当成轴向应力考虑的设计过于保守。
According to the formation and distribution of secondary stress in the solid joint of railway steel bridge, some samples were designed for secondary stress fatigue test. The influence of secondary stress on fatigue life was studied by biaxial fatigue test and was contrastively analyzed by finite element method. From fatigue tests and theoretical analysis, it is improper that the influence of secondary stress on fatigue life is neglected because the initial crack fatigue life bearing secondary stress is obviously shorter than that of bearing no secondary stress. It is also improper that secondary stress is totally substituted by axial stress when checking fatigue safety, because such design is too conservative.
出处
《中国铁道科学》
EI
CAS
CSCD
北大核心
2005年第2期77-79,共3页
China Railway Science
基金
铁道部科学发展计划项目(2001G010A 2)
关键词
钢桥
疲劳寿命
次应力
整体节点
双轴疲劳试验
Cracks
Fatigue of materials
Finite element method
Joints (structural components)
Steel bridges
Stresses
