Girder (construction)

In structural engineering, a beam is a girder that takes the load of a ceiling , arch or wall and transfers it to other components. The load-bearing capacity or the span of a ceiling or an arch can be increased in this way.

function

Beams can partially take on the function of load-bearing walls, but unlike these create a free passage. They are used, among other things, for the construction of large halls with flat ceilings, where previously a vault would have been necessary to bridge a larger span. In addition, beams are often added after the renovation of old buildings to improve the structural analysis .

history

Nowadays beams are mostly made of reinforced concrete or steel , which are either concreted with formwork on site or used as a prefabricated component. Historic buildings are usually wooden beams, but also stone constructions.

special cases

In addition to visible beams, there are so-called ceiling-level beams in which additional longitudinal reinforcement is integrated into the concrete slab in the area of the girder. The undersides of the beam and the plate to be supported thus merge seamlessly into one another. In the area of reinforced bending reinforcement, the plate meets the requirements of a conventional beam. The reasons for their planning and use are aesthetic, as well as the reduced formwork effort.

photos

Rib beams in the apse calotte of San Salvador de Cantamuda
Arch beams at the Pont de Vernay (Airvault)
Underlaying a footbridge between Italy and Switzerland near the Bagni di Craveggia