Variable Amplitude History Editing and Accelerated Testing of SAE 1045 Steel

The objective of this research was to determine if strain gate and SWT parameter history editing techniques can be used to accurately edit a variable amplitude strain history to predetermined damage levels. The log skidder bending strain history with 62 672 reversals was used as the full length variable amplitude history. By editing small damage cycles to 50% and 90% retained damage levels, the edited histories were reduced to between 0.3 and 11 percent of the full length history. Comparisons involving calculated and experimental fatigue lives of smooth uniaxial SAE 1045 steel specimens subjected to full length and edited histories were used to evaluate the editing techniques. Both the strain gate and SWT parameter editing techniques successfully edited the predicted amount of damage. These strain based techniques for removing small damage cycles are thus recommended for practical testing applications.