Steelconcrete composite slim floors with the steel beam encased in concrete floor slabs have many advantages

including low structural height

high fire resistance and rapid construction times. These features make such floors a promising for use in multistorey steel buildings. We established a 3D finite element model of a monolithic composite slim floor using the ANSYS software package. We analyzed the loading capacity

deformation behavior

natural vibration frequency

the influence of reinforcement

and the concrete in the floor rib under a uniformly distributed vertical load. We calculated the effective width of midgirder and secondary beams. The following conclusions can be drawn from the analysis results: First

monolithic composite slim floors possess high loading capacity for common buildings. Second

the concrete rib and reinforcement ratio in the rib have significant effects on floor loading capacity. Third

calculation of effective primary beam width should be based on analysis of monolithic floors rather than single beams.