STUDY ON THE MECHANICAL PROPERTY OF SELF-PIERCING RIVET AND ITS CONSTITUTIVE MODEL IN COLD-FORMED THIN-WALLED STEEL

To introduce self-piercing rivet connection to component connections of cold-formed thin-walled steel structures, shear and tension tests were designed and conducted both on self-piercing rivet connection and self-tapping screw connection specimens. Parameters in terms of end distance, thickness difference between connection components and rivet length were studied and their effects for shearing performances of self-piercing rivet connection were investigated. Based on the SIR model of transmission dynamics of infectious diseases, a constitutive model of riveting was established, and then the shear capacity design calculation method was proposed. The results show that the main failure mode is ductile failure with rivet legs being pulled out and part of rivet head being pulled out. Its stiffness, intensity and energy dissipation are better than the self-tapping screw connection. The established constitutive model can accurately reflect the variable trend of load-deformation curve of the self-piercing rivet connection and the error of shear capacity between theoretical value and experimental value is small. When self-piercing rivet was used in connections between cold-formed thin-walled steel sheets, the thickness of sheets should not be greater than 4 mm, the thickness ratio between thick plate and thin sheet should not be greater than 1.5 and the end distance should be 2 times more than the diameter of the rivet.