London Underground has more than 300 riveted bridges, 24 of which are more than 100 years old. Calculations suggested that many bridges had reached or exceeded their fatigue lives. The purpose of the investigation, therefore, was to provide an improved basis for fatigue assessment of riveted bridges. Strain range counting monitors were fixed in succession to four bridges, in order to ascertain the strain ranges that actually occurred in service. Also, parts of a riveted bridge that was to be demolished and replaced were fatigue tested at Imperial College. The laboratory tests on riveted girders, tensile specimens with holes, and rivets in tension, with published data from earlier tests, are used to propose a new stress range/fatigue life relation (S–N curve) for riveted girders, which approximately doubles the life predicted by BS 5400 for a given stress range.
Min Xie, BSc, MSc, PhD
Imperial College of Science, Technology & Medicine
G. T. Bessant, CEng, FICE London Underground Ltd
J. C. Chapman, FREng, FCGI, PhD, FIStructE, FICE, FRINA
Visiting Professor at Imperial College of Science, Technology & Medicine
Professor R. E. Hobbs, DSc, FCGI, PhD, CEng, FIStructE, FICE Imperial College of Science, Technology & Medicine