Fatigue life assessment of large scale T-jointed steel truss bridge components. (June 2017)

• Record Type: Journal Article
• Authors: Cai, Shunyao; Chen, Weizhen; Kashani, Mohammad M.; Vardanega, Paul J.; Taylor, Colin A.
• Is Part Of: Journal of constructional steel research. Volume 133(2017)
• Page Start: 499
• Page End: 509
• Publication Date: 2017-06
• Subjects: Steel bridges -- Welded joints -- Fatigue -- Cope holes -- Notch stress; Steel, Structural -- Periodicals; Building, Iron and steel -- Periodicals; Acier de construction -- Périodiques; Construction métallique -- Périodiques; 624.1821
• DOI: 10.1016/j.jcsr.2017.01.008
• Languages: English
• ISSNs: 0143-974X

Abstract

Abstract: Among current approaches for fatigue strength assessment, the effective notch stress method is widely employed by practising engineers designing welded joints. This is particularly important in the situation where the nominal stress and structural stress cannot be easily quantified. In this paper, the applicability of the so called effective notch stress approach on large-size T-joints in truss bridges is investigated through a comprehensive experimental programme supported by numerical analysis. A series of large-scale fatigue tests on prototype large-size T-joints with cope holes were conducted. These types of joints are normally used in fully welded truss bridges. Furthermore, a simple parametric study was conducted using finite element analysis to investigate the effect of plate thickness and cope-hole radius on effective notch stress. Comparison of the results with commonly used design guidance documents reveals that the effective notch stress approach provides a conservative estimate of the fatigue strength of the specimens tested in this experimental programme. Highlights: Large scale bridge components are tested to study their fatigue life. Results suggest that codified design curves such as IIW-FAT 225 are conservative. Influence of plate thickness and cope hole radius on fatigue notch factor is shown.