What type of loads are most responsible for causing rivet failures?

Rivet failures are primarily caused by shear loads because rivets are designed to hold materials together by resisting shear forces that attempt to slide one piece of material past another. In most structural applications, rivets are subjected to loading conditions where shear is the predominant stress type. When a shear load is applied, it directly influences the behavior of the rivet and can lead to deformation and eventual failure if the load exceeds the material's shear strength.

While tensile, bending, and compression loads are also relevant in various structural contexts, they do not primarily impose the failure mechanisms seen in rivets. Tensile loading can lead to tension failure and bending can cause additional stresses, but rivets are specifically designed to excel under shear conditions. Thus, shear loads are the most critical factor in assessing potential rivet failures.