What does joggle in removed rivet shanks indicate?

Joggle in removed rivet shanks typically indicates a partial shear failure. This deformation suggests that the rivet experienced significant stress during its service life, causing it to fail in shear rather than tension. The presence of a joggle means that one part of the shank was pulled or pushed in relation to its other part, which is a characteristic feature of failure due to shear loading.

Other options may relate to potential issues but do not specifically tie to the condition described. For instance, corrosion damage usually leads to uniform degradation rather than a localized deformation, and improper installation typically presents differently, such as misalignment or refusal to seat properly. Similarly, over-torqued rivets often cause a different type of failure, generally seen during the installation or initial service rather than as a permanent feature observed on removed shanks. Hence, recognizing a joggle is a clear indicator of past shear failure in the rivet.