Beam formed by the composite of steel and reinforced concrete. Both materials must be bonded to each other in a shear-resistant manner. First and foremost, a steel composite beam must withstand stresses on bending.
The form, dimensions and design of steel composite beams are regulated in Eurocode 4, in particular in DIN EN 1994-1-1 . If a sponsor cannot be clearly assigned, it requires general building authority approval.
In practice, so-called head bolt dowels have become established as composite agents. Only these are regulated in more detail in Eurocode 4. Other composite materials such as block dowels or loop anchors or similar may only be used with building authority approval.
Essentially, a distinction is made between steel composite girders and
a) girders with a visible steel profile: Here, the upper chord of the girder consists of concrete, e.g. in the form of an in-situ concrete slab, element slab or similar resting on the steel girder. The bond is mainly carried out via head bolts. The most common steel girder profile is the IPE profile, but other profiles or truss girders are also conceivable:
Image: Beams with visible steel profile - bauwion
b) Beams with concreted chambers: Here, the bridge of the steel girder is concreted out and specially reinforced, often for fire protection reasons. The concrete must be connected to the webway of the girder. This can be achieved by means of reinforcement brackets, head bolts or plug-in hooks guided through the web welded to the flange:
Image: Beam with concreted chambers - bauwion
Source: bauwion
