Experimental study on seismic behavior of steel structure with cellular beams and composite concrete slab

Quasi-static testing was conducted on a single-bay two-story cellular steel beam structure with composite concrete slab to evaluate the seismic performance of the frame under cyclic lateral loading. Test measurements of the cellular beams, joints, columns, and slabs were presented and analyzed in detail. The failure modes and damage mechanisms of the specimens were investigated, and the hysteresis behavior, strength and stiffness degradation, ductility, and energy dissipation of the structure were analyzed. The composite effects of the concrete slabs under cyclic loads were also evaluated. The results indicate that the structure exhibited a full hysteresis loop, and the structure had a good capacity for energy absorption. After the peak load of the skeleton curve for the upper frame layer had been reached, the bearing capacity of frame A decreased more rapidly than that of frame B, and the strength attenuation and stiffness degradation were more obvious for frame A. The ductility coefficients of the upper layers of the two frames were both greater than 3.0. Through the analysis of the destruction process, the failure mode of the frame was researched. Plastic hinges were formed around the opening before the joints yielded, and the positions of the plastic hinges were a considerable distance from the beam-to-column joints. Damage to the structure was presented as a typical plastic hinge failure, which protected the beam-to-column nodes and avoided brittle failure.