SELF-STRESSING METHOD OF REINFORCED CONCRETE BEAM Russian patent published in 2020 - IPC E04C3/294 

FIELD: construction.

SUBSTANCE: invention relates to construction, namely, to self-stressing method of reinforced concrete beam used in ceilings and coatings of buildings. Proposed method comprises installation of lower belt out of steel section with anchor joints and laying monolithic concrete of upper belt by formwork. For period of hardening of concrete to retain deflection of beam from shrinkage of concrete temporary supports are installed in middle of span, which are removed after stabilization of internal moments from shrinkage, values of which are determined by proposed mathematical dependence. To increase bearing capacity and rigidity of beam before concrete placement in middle of span temporary post is installed – support, monolithic concrete is laid, after shrinkage of concrete (approximately two weeks later), internal stresses create internal forces and moment of reverse sign, which leads to formation of self-stressed beam. At that value of internal moments from concrete shrinkage is determined by mathematical dependence. Proposed method for self-stressing of beams or flooring in comparison with known solutions of pre-stressing of beams and floors provides for simplified manufacturing, absence of tensioning devices, reduced consumption of materials. Produced pre-stressed concrete beam or flooring has high carrying capacity, stiffness and reliability.

EFFECT: technical result of invention consists in improvement of beam carrying capacity.

1 cl, 4 dwg