Composite action in shallow floor beams with different shear connections

Shallow floor beams, abbreviated to SF beams and also known as slim floor beams, are beams where most of the beam member is embedded in the concrete decking of the floor, which is supported on the lower flange or outward ledge of the beam. SF beams are composite members in which composite action can be utilized in both the serviceability and ultimate limit state conditions or only at the serviceability limit state, depending on the decking type. This paper discusses the composite action in SF beams when the decking is of a solid type, i.e. consists of a reinforced concrete slab or composite slab with profiled sheeting, making it possible to benefit from the composite behaviour at all important limit states. Hollow-core decking supported on SF beams is a special case in which the composite action can only be employed in the design for serviceability conditions. Another paper covers the special issues regarding the design of such shallow floors.