METHOD TO MEASURE STRESSES IN STRUCTURE WITHOUT REMOVAL OF STATIC LOADS Russian patent published in 2015 - IPC G01L1/00 G01B7/16 

FIELD: instrumentation.

SUBSTANCE: measurements of surface deformations ε are carried out in controlled points on a structure, which is in stressed-deformed condition. Controlled points are selected so that they are capable of additional loading regardless of the structure. In controlled points they create with the help of the available external force P, additional stresses that match in direction with the measured ones, deformation is stepwise increased by Δε, change of the external force is measured ΔP_i. Loading is increased until $$K=\left|\frac{\Delta P_{i+1}}{\Delta P_i}-1\right|*\Delta \epsilon$$ increases to the value corresponding to the normalized deviation of mechanical characteristic of structure material from the Hooke's law. Structure deformation is determined, subtracting measured additional deformation from the available value of deformation for the previously known mechanical characteristic of structure material.

EFFECT: simplified process of measurement and no damage to integrity of the investigated structure.

3 cl, 3 dwg