Study of a new type of self-centering beam-column joint in steel frame structures

A new type of self-centering beam-column joint with installed steel arc plates is proposed in this study. First, mechanical behavior of the self-centering joint using prestressed steel strands to provide the centering force is theoretically analyzed in detail, followed by experimental validation. New joints with different arc plate parameters are designed and tested under cyclic loading. Test results show that the hysteretic curve of the new joint exhibits typical characteristic of self-centering capacity. By parametric analysis of five design parameters of the arc plate, it is found that vector height has the greatest influence on the joint's moment-rotation skeleton curve, which is consistent with experimental findings. A simplified model of the joint is built in OpenSees to simulate its hysteretic behavior, which agrees well with the tested results. To demonstrate the effectiveness of the new joint to improve the seismic performance of the overall structure, a series of nonlinear time history analysis on a steel frame structure with the new joint under earthquakes are conducted, which show that the joint is particularly effective in reducing the residual interstory drift response.