METHOD OF DETERMINING RESIDUAL STRESSES IN ARCHED PROFILES

摘要

FIELD: construction.;SUBSTANCE: invention relates to the field of structural mechanics and can be used for determination of longitudinal residual stresses in normal sections of arched profiles with subsequent allowance for these stresses during design of structures. Essence of the proposed method consists in the fact that in the shelf with the known radius of the upper surface of the shelves of the arched steel thin-walled cold-bent profile with trapezoidal corrugations, two basic holes with diameter d=3–5 mm, arranged along the axis Z with distance along the arc between each other are made L₁=100–200 mm, and the chord length is measured c₁ between the base holes. Further, with symmetrical coverage of the base holes, a U-shaped through-cut is made in the investigated flange with width b=8–12 mm, followed by repeated measurement of the chord length c₂ between the base holes when the cut strip is fixed in the alignment of the flange. According to measurements of chord lengths c₁ and c₂ between base holes before and after making U-shaped section in the shelf, values of longitudinally oriented normal residual stresses σ_{z res} in the shelf of arched steel thin-walled cold-bent profile with trapezoidal corrugations are determined by formula.;EFFECT: technical result consists in determination of residual longitudinally oriented normal stresses in flanges of arched steel thin-walled cold-bent profile with trapezoidal corrugations with following allowance for these stresses at designing arch structures.;1 cl, 7 dwg