Abstract
Fatigue strength of welded details in long life region, for example over five million cycles, is essential for fatigue design of bridge components, because the stress ranges measured in service are often in this range. Constant amplitude fatigue tests on 200mm long gussets welded to tensile plates and tensile flange of beams and on 200mm long cover plates subjected to low stress ranges were carried out, and constant amplitude fatigue limits were evaluated. The test results on 200mm long gussets were compared with fatigue crack propagation life computed using the Monte Carlo simulation technique. The analytical results were generally in good agreement with the test results in the finite life region. However, the predicted fatigue limit using a threshold value of stress intensity factor range was lower than the runout level of test data.
