Service life estimation of self-piercing riveted joints by linear damage accumulation

Tests under variable amplitude loading on self-piercing riveted components with semi-tubular rivets result in longer service lives than those calculated by linear damage accumulation. An overview of the literature shows that damage sums greater than one are found for other types of riveted joints either, while an explanation for this unusual behavior is still missing. Therefore, this behavior is examined in more detail. A correlation is shown between the damage sum and the hardness of the load spectrum. Considering this correlation, the accuracy of the service life estimation can be improved significantly.