【摘要】 针对正交异性钢桥面板焊缝构造细节,开展疲劳应力有限元分析,探讨不同影响因素的疲劳效应,为钢桥面板抗疲劳设计和维护提供参考。通过顶板与U肋焊缝细节二维平面模型,设置不同焊趾过渡半径、过渡角与焊瘤缺陷参数,研究焊缝疲劳应力的变化情况。建立钢桥面板节段模型,考虑不同荷载工况组合加劲肋构造对U肋与横隔板细节裂纹萌生点疲劳应力的影响。研究结果表明:焊趾应力集中随过渡半径或过渡角的增加而降低。随焊瘤高度的增加,焊瘤宽度对应力集中的影响减弱;随焊瘤宽度的增加,焊瘤高度对应力集中影响增强。设置横隔板加劲肋可降低U肋与横隔板细节裂纹萌生点应力,提高该细节疲劳性能。更多还原

【Abstract】 A finite element analysis is conducted to study fatigue stress of weld seam in orthotropic steel bridge.Fatigue effect of varied influencing factors is studied,which can provide reference for anti-fatigue design and maintenance of steel bridge deck.A 2 D FEM of rib-to-deck joints is established to study the fatigue stress of weld,with different parameters in welding toe transition radius,transition angle and weld beading defects.And another segmental model of steel bridge deck is established to analyze the effect of stiffener structure on the fatigue stress of crack initiation on rib-to-diaphragm welded joint.The result shows that the increase in radius and angle of transition is believed to result in the decline of the stress concentration on weld toes.With the increase of the height of the weld,the influence of the width of the weld on the stress concentration is weakened.With the increase of the width of the weld,the influence of the height of the weld on the stress concentration is enhanced.Moreover,the stiffener to the diaphragm can contribute to the decrease in stress of the crack initiation on rib-diaphragm joint,which is in favor of the improvment of fatigue performance of the detail.更多还原