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由于经济原因,欧洲和北美仍存在大量还在使用的老式铆接桥梁。这些桥梁要承受日益增长的交通强度,使用期限也较长,因此需要对它们的损害程度进行准确的评估,决定是否对其进行维修。大部分老式铆接桥梁在最初设计时并没有考虑疲劳因素,所以疲劳失效是个问题。此外,关于这种结构的疲劳性能的研究有限,对旧建筑材料(熟铁、锻铁、旧钢材)和铆接连接的了解也不充分,所以缺少对这种铆接桥梁进行全面的疲劳评估的方法。介绍一座来自葡萄牙、具有百年历史的桥梁——Fo桥的锻铁的疲劳特性。同时,研究由同种锻铁制造而成的铆接和螺栓连接节点的疲劳性能,以及压应力对螺栓节点的影响。除了恒幅荷载以外,也对铆接节点变幅疲劳荷载进行调查,从而严格地评估其线性损害程度。
Due to economic reasons, there are still a large number of old riveting bridges still in use in Europe and North America. These bridges are subject to increasing traffic intensity and have a longer lifespan, so they need to be accurately assessed for the extent of their damage and whether they will be repaired or not. Most old riveted bridges did not consider the fatigue factor when they were originally designed, so fatigue failure is a problem. In addition, there is limited research on the fatigue properties of such structures, and inadequate knowledge of the old building materials (wrought iron, wrought iron, old steel) and riveted connections, there is a lack of comprehensive fatigue assessment of such riveted bridges. Describe the fatigue properties of a wrought iron from Fono Bridge, a 100-year-old bridge in Portugal. At the same time, the fatigue properties of riveted and bolted joints made of the same kind of wrought iron and the influence of compressive stress on the joints of the bolts are studied. In addition to the constant amplitude load, the luffing fatigue load at the riveted joint is also investigated to assess the degree of linear damage strictly.