摘要
正交异性钢桥面板横隔板切口处疲劳问题突出,裂纹通常萌生于切口自由边以及切口起始处纵肋-横隔板连接焊缝。为研究不同切口型式对疲劳细节应力的影响,建立有限元分析模型,获得细节在轮载下的应力响应。研究结果表明:切口自由边细节是面内应力主导,且较大的切口半径有利于降低应力水平;纵肋腹板在平行于焊缝方向的外侧应力最大,属于纵肋-横隔板连接焊缝中最不利的细节,因此该连接处的裂纹通常会萌生于焊缝末端的纵肋腹板外侧,并沿垂直于焊缝的方向扩展;对于纵肋-横隔板连接焊缝的横隔板细节,当切口型式为相切过渡的方式时,面外应力远小于垂直过渡的方式,而面内应力相反;采用Eurocode 3中推荐的切口型式是合适的。
The fatigue problem of floorbeam cutout in orthotropic steel bridge deck is serious, and the cracks often initiate at the free edge of cutout or the rib-to-floorbeam weld at the start of cutout. To investigate the effects of various cutout types on stress behavior of fatigue-prone details, finite element models were established to obtain stress responses of the details under wheel loads. The results indicated that the stress at the free edge of cutout was dominated by in-plane stress, and large cutout radius facilitated to decrease the stress level. The stress of rib wall outside was maximum in the direction parallel to the weld, which was the critical detail of rib-to-floorbeam weld, hence the crack often initiated at the rib wall outside of weld end and propagated along the direction normal to the weld. For floorbeam detail in the weld, the out-of-plane stress in the cutout type with tangent transition was far smaller than that with vertical transition, while the in-plane stress was reverse. The cutout type recommended in Eurocode 3 was applicable.
作者
向泽
祝志文
XIANG Ze;ZHU Zhiwen(College of Urban and Rural Construction, Shaoyang University, Shaoyang 422000, China;Department of Civil and Environmental Engineering, Shantou University, Shantou 515063, China)
出处
《铁道科学与工程学报》
CAS
CSCD
北大核心
2019年第2期399-407,共9页
Journal of Railway Science and Engineering
基金
国家重点基础研究发展计划(973计划)项目(2015CB057701)
国家自然科学基金资助项目(51878269)
湖南省交通科技资助项目(201522)
关键词
正交异性钢桥面板
疲劳
有限元分析
切口型式
热点应力
orthotropic steel bridge deck
fatigue
finite element analysis
cutout type
hot-spot stress
