The spectral analysis of the state parameters of technical systems in the regular and damaged states

It is noted that reaction of bearing elements of structures and engineering components to service loadings, impacts of physical fields and corrosive environments is initiation not only fields of stresses and strains, but also fields of damages. At the same time depending on conditions of a loading and environment various mechanisms of accumulation of damages and fracture which indicators are essential changes in spectra of a response of technical systems to different impacts are realized. The analysis of parameters of a state of such systems by registration of spectral characteristics of service processes allows to carry out estimations of levels of their damage in rather full degree. On the basis of results of research of service states of technical systems on spectral diagnostic parameters approaches to the analysis of amplitude-frequency characteristicses of their actual states both in the regular allowed states, and upon transition to dangerous states owing to accumulation in them of dangerous service damages are offered. At the same time criteria of transition of technical systems from regular in emergency and catastrophic states at accumulation of critical limits of damage are formulated. Examples of the dispersed initiation of microcracks in material of structures parts at a cyclic deformation with their propagation in the main fractures, and also examples of the analysis of dynamic states on vibration spectra of a response of simple and compound technical systems with the crack which arose in them and with existence of defects are given. At the same time the possibility of obtaining initial computation and experimental information on parameters of a stress-strain state and damage of installation with use of methods of the spectral analysis of a response of a compound structure to vibration impact as a result of initiation of damage of its separate parts is shown. Results of such spectral analysis can be used for diagnostics and monitoring of conditions of regular service of high-loaded installations of a technosphere and transition of their states to limit emergency and catastrophic in relation to objects of power engineerings, space-rocket and aircraft equipment.

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