Fatigue of Curved Steel Bridge Elements - Effect of Heat Curving on the Fatigue Strength of Plate Girders

摘要

This multiphase investigation involves the performance of five tasks: (1) analysis and design of large scale test assemblies, (2) special studies of selected topics, (3) fatigue tests and (4) ultimate load tests of test assemblies, and (5) development of design recommendations. This report presents the results of a special study (Task 2) of the effects of heat curving on the fatigue strength of plate girders. The reports listed in Appendix B document other phases of this investigation. Following a survey of the available literature on heat curving, an analytical parametric study of the residual stresses and strains due to heat curving is presented. The results of the parametric study are then examined for their applications to fatigue. Two mechanisms are considered: (1) mean stress effects on fatigue crack growth, and (2) fatigue crack growth at web boundaries due to excessive web bowing. The results of this study indicate that heat curving has no significant effect on the fatigue strength of plate girders.