Demand stiffness ratio and earthquake response analysis of rocking truss-steel frame system

As a new structural system with good engineering applications, the rocking wall system has been accepted by more and more engineers. However, rocking walls have high self-weight, which also increase the total weight of structures. Rocking concrete walls are easy to crack. The deficiencies of rocking walls are problems that the researchers have been confronting. In view of the shortcomings of the traditional rocking wall system, a rocking truss-steel frame system was put forward in this paper. Meanwhile, a design method of the rocking truss-steel frame was proposed and a design recommendation based on demand stiffness ratio was presented. Based on time history analysis under frequent, moderate and rare earthquakes, the energy absorbing capacity and cumulative displacement ductility of energy dissipation components were analyzed. Moreover, the plastic hinge developing process of structural failure modes was discussed. The results show that the failure modes of steel frame structures can be improved, optimized and controlled by the adoption of a rocking truss-steel frame system, so the seismic performance of the structures can be improved. As a new type of rocking structures, the resilience of the rocking truss-steel frame system is more effective than traditional seismically designed structures.