Synthesis of Measurement Method of Stressed — Deformed Condition of Complex Structures

Abstract

Nowadays the most common instruments of measuring the stress-strain state of complex structures are strain gauges. As a rule, strain gages are connected to the measuring system according to the bridge scheme, it provides elimination of systematic errors of measurement and compensation of temperature deformations. The principles of constructing, designing and mathematical modeling of deformation and stresses of complex technical constructions with the help of strain gauges taking into account destabilizing factors are developed, which allows to significantly reduce the level of errors in relation to existing methods of measurement and known analogues. The analysis of the main destabilizing factors that limit the accuracy of measurement using strain gauge is carried out, are (Fig. 1—4): the random processes (noises, obstacles, etc.); the time changes of parameters of measuring transducers due to aging and physical degradation; the influence of external climatic and mechanical factors (temperature, humidity, etc.). The temperature error values are set for the most common alloys used for the manufacture of strain gauges, namely: constantan and karma. This work is aimed at finding ways to improve the accuracy of remote measurements and impedance of measuring devices of the stress — strain state, in particular strain gauges and strain gauges, by introducing improved theoretical calculations taking into account destabilizing factors, which makes it possible to reduce the level of errors with respect to known analogs in dozens of times.