METHOD FOR COMBINATION PRESTRESSING OF PERFORATED TRUSSED BEAM Russian patent published in 2002 - IPC

FIELD: construction, applicable in manufacture of building metalworks, in particular, in prestressing of perforated trussed beams. SUBSTANCE: the method consists in installation of the members of the perforated stiffening beams obtained by zigzag cutting of the starting section with a variable height of corrugations, one above another with an engagement in their middle parts, then joining to one of members of the beam struts and tie bar, flexible bend of the members until the projecting edges of the corrugations come in contact with one another and their subsequent welding. After installation of the beam members one above another, rotary posts are connected to one of them with a shift of their ends with the guide locks towards its middle, and T-shaped rotary posts with attached loop-shaped yokes are installed slantwise on the end sections, they are set up in the C-shaped guides positioned on the ends sections of the other member of the perforated stiffening beam. After that, the tie bar provided with a tensioning device is fastened in the guide locks and connected to the ends of T-shaped rotary posts. Then, the tie bar is stressed by the tensioning device, bending thereby the members of the perforated stiffening bar until all the projecting edges of the corrugations come in contact with one another, they are welded, and the tie bar is subjected to after-stressing. EFFECT: reduced labor content of prestressing of perforated trussed beams and reduced specific consumption of materials. 2 cl, 7 dwg