Fatigue Crack Repair of Steel Beams with Tapered Cover Plate Details

Abstract

The fatigue strength of beams with tapered cover plates was investigated both experimentally and analytically. The test specimens were precracked and then repaired with one of the following three methods: a friction type bolted splice plate connection, air-hammer peening along the weld toe, and a hybrid of the previous two called the partial bolted splice connection. Test results demonstrated that the bolted splice connection was the most effective repair method. Cracked cover plate ends repaired with a bolted splice connection, partial bolted splice connection, and air-hammer peening demonstrated an increase in fatigue life equal to categories B, C, and D of the American Association of State Highway and Transportation Officials (AASHTO) specifications, respectively. Air-hammer peening was found to be particularly effective if applied to noncracked cover plate ends, with an increase in fatigue life equal to category B′. An analytical model was developed to predict the propagation life of cracked cover plate ends repaired with one of the three repair methods.