Experimental and analytical studies on tensile behavior of kinked steel plates

Abstract

A novel kinked steel plate (KP) configuration was proposed in the literature with the characteristics of large deformability. Using this KP configuration in frame beams, progressive collapse resistances of the frame structures can be significantly improved without affecting their seismic performance. In the present study, the load−deformation properties of the KPs under uniaxial tensile loading are investigated. First, tests are conducted to understand the tensile behaviors of the KP specimens varying in height-length ratio (the ratio of wave height to wavelength of a KP). Second, an analytical model is proposed to predict the equivalent stress–equivalent strain relationship of the KPs. This model is derived based on the principle of static equilibrium and the load−deformation relationship. Third, the residual stress distribution of the KPs after cold-forming is investigated based on the finite element (FE) analysis. Discussions are presented including the influence of steel plate thickness on the equivalent stress−equivalent strain curves of the KPs. Test and analytical results confirm that the equivalent stress–equivalent strain relationship of the KPs can be presented in a three-stage profile. The analytical model possesses appropriate accuracy with the errors less than 8.5% compared with test data. The results from the FE analysis indicate that the steel plate thicknesses varying from 2 mm to 12 mm result in the initial stiffness of the KPs increasing by 16 times and the ultimate strain decreasing by 17.3%.