Consideration of composite effects on elasto-plastic behavior of panel-zone

Composite effects of a concrete slab have been observed in not only steel beams but also panel-zones. Considering strength-baiances between steel members, total-collapse mechanism would be realized. Therefore, it is very important to consider the composite effects on clasto-plastic behavior of steel beams and panel-zones at the stage of seismic design. Composite effects on elasto-plastic behavior of steel panel-zone are discussed in this paper. Cyclic loading tests of four beam-column subassemblies with a concrete slab were carried out to evaluate composite effects. Concrete slabs led to increase in initial elastic stiffness and yield strength of panel-zone. Based on observing these test results, the evaluation-model for composite effects on panel-zone were established. Finally, composite effects were proven in nonlinear analysis considering inplane-shear transfer between steel beam and concrete slab.