Experimental study of seismic performance of PEC column-steel beam 3D frame with endplate connection

Abstract

The design and quasi-static test of a 1/3 scale down the single-story partially-encased composite structure of steel and concrete (PEC) column-steel beam 3D frame with endplate connection has been completed, confirming that the PEC is a new composite structural system that combines the advantages of concrete and steel structures. The damage mode and yielding mechanism of the frame by strain variation were analyzed, and its seismic performance was evaluated. The results show that the concrete filling in the node domain of the PEC column can activate the strut and tie mechanism for transferring the compression force between the column and the slab. The yield mechanism of the frame is “beam-column-node,” which satisfies the design principles of “strong column but weak beam” and “strong connection but weak component.” The full hysteresis curve has excellent energy dissipation capability. The strength degradation is stable, and the ductility coefficient is >2.85. The elastic inter-story and the elastic-plastic inter-story displacement drift meet the design requirements, which indicates that the frame has a stable bearing capacity, excellent flexibility, and anti-collapse capacity.