PERFORATED BEAM Russian patent published in 2015 - IPC E04C3/08 

FIELD: construction.

SUBSTANCE: perforated beam is made of rolled double-tee shape, cut along the axis of the wall with certain contour for each half of the beam and welded by protruding parts of the produced halves so that holes in the form of an ellipse are produced. Elliptical holes have different angle of inclination of the main axis of the ellipse to the axis of the beam. The central elliptical hole with its main axis is arranged perpendicular to the longitudinal axis of the beam, and others - at the angle of 45 degrees symmetrically relative to the centre of the beam. Elliptical openings may have the angle of inclination smoothly changing from 90 degrees in the centre of the beam to 45 degrees in support sections symmetrically to the centre of the beam.

EFFECT: reduced concentration of stresses in a wall of perforated beams, which results in increased reliability and durability of structures.

3 cl, 9 dwg, 1 tbl