Pages 341-342
The method of fatigue life prediction is presented for structures under flow-induced vibration. A small wind tunnel was made and used to reproduce fatigue failure by flow-induced vibration. A medium carbon steel specimen attached to a larger styrofoam cylinder was fixed to the experimental equipment. A small artificial hole was introduced onto the specimen surface. A small portable strain histogram recorder (Mini Rainflow Corder, MRC) developed in another project of the authers' team was used to acquire the service strain histogram at a critical point of the specimen. Fatigue damage D defined by the Modified Miner Rule was calculated by using the strain histogram at the initial stage of the test. The values of D were all smaller than 1.0 and ranged approximately from 0.2 to 0.8. The effect of initial defect size on the values of D was clarified by focusing the relationship between small crack growth behaviour and strain histogram.
