Analysis on local stress at bulb flat rib-diaphragm connections in a lightweight composite bridge deck
Zhang Shihong1,2 Shao Xudong1 Cao Junhui1 Cui Jianfeng3 Hu Jianhua3
1. Hunan University, Changsha 410082, China
2. Henan Provincial Communications Planning,
Survey and Design Institute Co., Ltd., Zhengzhou 450052, China
3. Hunan Provincial Communications Planning, Survey and Design Institute, Changsha 410008, China
Abstract：In order to decrease the risk of fatigue cracking in orthotropic steel decks, a lightweight composite bridge deck with bulb flat ribs was proposed. As a typical bridge with lightweight composite bridge deck, the Sencond Dongting Lake Bridge is taken as an example, in which the local finite element models of steel truss girder and the sub-models of bulb flat rib-diaphragm connections were established. Then the shape of cutouts and thickness of diaphragms were investigated based on the hot spot stress method. The results show that the fatigue properties of 3 typical details at bulb flat rib-diaphragm connections were affected significantly by the thickness of diaphragms. On the basis of comprehensive comparison, it is concluded that the fatigue properties of apple-shaped cutout are the best. Additionally, fatigue test was performed on a full-scale model to verify the fatigue strength of 3 details at bulb flat rib-diaphragm connections in a lightweight composite bridge deck with 16mm diaphragms and apple-shaped cutouts. In the test, the fatigue stress range for the most unfavorable detail, i.e. the free edge of the cutout, was 90.6MPa and no fatigue cracks developed after 2.5 million loading cycles. The research results show that the key details in the lightweight composite bridge deck with bulb flat ribs have good fatigue performance and can satisfy the design requirements of Sencond Dongting Lake Bridge.
张士红 邵旭东 曹君辉 崔剑峰 胡建华. 轻型组合桥面板球扁钢纵肋-横隔板连接细节局部应力分析[J]. 土木工程学报, 2016, 49(12): 97-107.
Zhang Shihong Shao Xudong Cao Junhui Cui Jianfeng Hu Jianhua. Analysis on local stress at bulb flat rib-diaphragm connections in a lightweight composite bridge deck. 土木工程学报, 2016, 49(12): 97-107.
