Utilizing the structural detail method to access the fatigue service life-tractor-trailer vehicle frame example

摘要

The purpose of this paper is to examine current methods of fatigue service life prediction utilizing the example of a tractor-trailer frame assessment. The paper will compare the use of traditional constant-life or "Goodman" diagrams and the application of the structural detail method to the prediction of fatigue service life. Constant-lifetime diagrams are generated using small smooth specimens and fatigue studies conducted in recent years on full size structural elements have revealed that fatigue life predictions based on the cosntantlifetime diagram were overly optimistic. A more conservative approach emerged from there studies, which utilizes S-N curves based on nominal stress ranges and the classification of structural details according to fatigue potential.