Formulation of design guideline for long-life steel girder bridges

实现长寿命桥梁，疲劳是重要问题之一。提出了保证桥梁在车辆荷载作用下疲劳安全的设计准则。其次，对三梁钢筋混凝土板桥进行了大型三维有限元分析，并对次构件进行了应力分析。有人指出，次级成员的建模需要特别注意。在钢筋混凝土板足够刚性的情况下，现行规范规定的梁桥加劲构件大多不能从疲劳的角度加以论证，虽然无法提出钢桥涂装的替代方案，但事实表明，高质量的涂装是实现长寿命的合理选择。对钢箱梁内部除湿系统进行了试验研究。

To achieve long life bridges, fatigue is one of the important issues. A design guideline to ensure fatigue safety of bridges under vehicle loading was presented.In the next place, large 3D FEM analysis was conducted for 3-girder RC-slab bridge and stress in secondary members was studied. It was pointed out that modeling of the secondary members requires special attention. Provided that the RC slab is stiff enough, most of stiffening members in the girder bridge according to the present code is not justified from a viewpoint of fatigue.Although alternative to painting of steel bridges could not be proposed, it was shown that high quality painting is a rational choice toward long life. Dehumidification system for interior of the steel box girder was experimentally studied.