Failure criteria and onsert shape optimization

The onsert is a joining element to achieve load introduction into lightweight structures typical for the transportation sectors. The onsert is simply bonded to the surface of the otherwise unharmed substrate. Thus, and in contrast to other joining technologies such as inserting, riveting, or bolting, the onsert technology avoids weakening of the structure. Previous work validates the predictions of the here used shape optimization procedure to achieve maximum static strength. The present study details active-constraint handling mechanisms avoiding locking effects when using the polynomial weight function variables to define shape. The optimization procedure is used to investigate the influence of various failure criteria to predict bond failure on the resulting onsert designs.