Fatigue performance of thermally cut bolt holes in structural steel S460M

Current fatigue codes only consider the fatigue performance of drilled and punched holes, limiting the use of thermal cutting processes to produce bolt holes. This paper studies the fatigue performance of structural steel S460M plates containing thermally cut bolt holes. The research covers three thermal cutting methods: the traditional one (oxy-fuel cutting) and two more modern processes (plasma and laser cutting). Specimen geometry is defined by a rectangular cross section with a cut hole in the middle. All the specimens were conducted to failure by applying fatigue cycles, the stress ratio (R) being 0.1. The corresponding S-N curve and fatigue limit were obtained for each cutting method. Fatigue results have been compared with previous researches on fatigue performance of drilled and punched holes, and with the predictions provided by current fatigue standards, analyzing the possibility to extrapolate their S-N curves, focused on drilled and punched holes, to thermally cut holes

Fatigue assessment of a railway bridge detail using dynamic analysis and probabilistic fracture mechanics

This paper presents a generic methodology for the use of PFM within the context of bridge loading for the fatigue design and assessment of steel railway bridges and provides detailed guidance on how to use the proposed methodology in order to carry out a PFM-based fatigue assessment. The problem is set in a probabilistic context to take into account material, loading as well as modeling uncertainties. Guidance is given on how to calibrate a constant amplitude PFM analysis against an S-N curve. Finally, as a case study, a cracked welded bridge detail is considered and its time-dependent fatigue reliability is established © 2012 Taylor & Francis Group

Recommendations for fatigue design of welded joints and components

This book provides a basis for the design and analysis of welded components that are subjected to fluctuating forces, to avoid failure by fatigue. It is also a valuable resource for those on boards or commissions who are establishing fatigue design codes. For maximum benefit, readers should already have a working knowledge of the basics of fatigue and fracture mechanics. The purpose of designing a structure taking into consideration the limit state for fatigue damage is to ensure that the performance is satisfactory during the design life and that the survival probability is acceptable. The latter is achieved by the use of appropriate partial safety factors. This document has been prepared as the result of an initiative by Commissions XIII and XV of the International Institute of Welding (IIW)