Experimental investigation of unequal-depth-beam-to-column joints with t-shape connector

This paper presents the seismic behavior of unequal-depth-beam-to-column joints connected by a T-shape connector. Three specimens are examined under cyclic loading tests. The primary experimental parameters are joints with or without T-shape connectors and beam depth ratio (Db2/Db1) with values of 0.5 and 0.75. The panel zone shear strength of unequal-depth-beam-to-column joints connected by a T-shape connector is 20% higher than that of common unequal-depth-beam-to-column joint under the same conditions. The influence of beam depth ratio on the panel zone shear strength of unequal-depth-beam-to-column joints connected by a T-shape connector is limited. The contribution of the T-shape connector web on the flexure moment of whole beam is less than 3%, indicating that the T-shape connector web does not resist the flexure moment but resists the shear force. Hysteresis curves of the panel zone for unequal-depth-beam-to-column joints connected by T-shape connectors are stable, showing excellent ductility and energy dissipation capacity. The equivalent viscous damping coefficients corresponding to the three specimens range from 0.47 to 0.51 in the ultimate stage. A design method for the T-shape connector is proposed and the calculation formulas are deduced.