Assessment approach for multiaxial fatigue damage of deck and U-rib weld in steel bridge decks

作者：Fu, Zhongqiu; Wang, Yixun; Ji, Bohai^*; Liu, Tianjia

来源：Construction and Building Materials, 2018, 189: 276-285.

DOI：10.1016/j.conbuildmat.2018.08.149

• Steel bridge deck
• Fatigue
• Multiaxial
• Assessment approach
• Damage

Assessment approach for multiaxial fatigue damage of deck and U-rib weld in steel bridge decks was studied. The orthotropic steel bridge deck was modelled to analyse the multiaxial stress state of the weld under wheel load. A multiaxial fatigue loading experiment was carried out to assess the fatigue strength of deck and U-rib weld based on equivalent stress and maximum principal stress. The critical plane approach which is suitable for deck-U rib welds was also established. The assessment results were then compared to those obtained by uniaxial fatigue approach. Reasonable multiaxial fatigue principles were proposed for deck and U-rib welds in different positions. The results show that multiaxial fatigue stress is observed in the deck-U rib weld. The shear stress may exceed normal stress and become the main reason for fatigue damage, thus a multiaxial fatigue approach is necessary for fatigue damage assessment. The nominal stress approach is suggested for fatigue assessment of deck and U-rib weld between diaphragms, which leads to conservative results and is more applicable to engineering practice. The critical plane approach is suggested for fatigue assessment of deck and U-rib weld on the diaphragm considering multiaxial fatigue effects and non-proportional stress in the weld.

• 出版日期2018-11-20
• 单位河海大学