Resistance of stud shear connectors to fatigue

Abstract

The three relationships that have been proposed for use in design for fatigue of shear connectors in composite beams are compared, with reference to all relevant test data on welded stud connectors. Statistical analyses of these data are presented. The wide range of values found in research for the exponent m, in the usual expression for the fatigue endurance, is due not just to differences in the test methods used, but more notably, to two schools of thought on how the results should be analysed. A recommendation is made on this important question, which does not appear to have been considered before. Background information and comment are provided on the relevant clause of the draft Eurocode for composite bridges, relevant to its conversion into EN 1994-2. The resistance formulae now proposed are inconsistent with that in the British Bridge Code to an extent sufficient to influence practice, especially assessment.