METHOD OF ESTIMATING BENDING STRESS IN ELEMENTS OF STRUCTURES Russian patent published in 2016 - IPC G01N27/72 

FIELD: measuring equipment.

SUBSTANCE: invention relates to diagnostics of technical state of metal structures, while in operating condition. On controlled section of sample (analogue) of element (or on operating element) in absence of external bending force and at application of external bending force (within limits of elastic properties of element) each time is magnetised in order to create symmetric magnetic field relative to axle (axes) of symmetry of element cross section geometric shape. Value of magnetic field induction is measured in characteristic points on boundaries of element cross sections, symmetrical to each other relative to axle (axes) of symmetry of element cross sections. Mean difference of absolute values of magnetic induction is determined in characteristic points on controlled section. At experimental dependence of bending force (or average tension in material) from mean difference of absolute values of magnetic induction in characteristic points on the monitored section of the sample (analogue of element or on operating element) analytical relationship is found. On controlled section of structural member in working state, symmetric magnetic field relative to geometrical figure section element is created, value of magnetic field induction is measured in specific points of sections, average absolute difference values of magnetic induction is determined in similar characteristic points and at earlier obtained analytical relationship, average estimated value of tension in material on controlled element section in working structure is found.

EFFECT: possibility to provide rapid evaluation of bending stresses in material of structure elements in working condition, by means of simple mobile equipment.

1 cl, 10 dwg, 1 tbl