Influence of steel strength on the fatigue reliability of welded structural components

A formulation is presented for the fatigue reliability assessment of imperfect structural components. The model adopts the R6 method, which combines the linear elastic fracture mechanics approach and the full plastic collapse. The utilisation of different steel strength and design solutions is studied. Reliability is predicted by a time variant formulation and the effect of maintenance is taken into account. It is shown that the savings in cost due to lighter structure of higher strength steel are mitigated by the cost of more frequent inspections and eventually repairs.