Methods for Diagnosing the Exhausted and Predicting the Remaining Life of Critical Engineering Facilities

Based on the concept of damaged material and its subsequent failure, an approach to analyzing non-isothermal viscoplastic deformation of “hazardous” zones of long-term engineering structures is presented. The approach allows for consideration of the influence of multi-component stresses and rotation of the principal axes of stress-strain tensors on the rate of damage accumulation; and nonlinear defect accumulation. The purposes of the calculation methods in this approach are: experimental studies of material properties; estimates of the exhausted and remaining service life of engineering structures based on a given loading history; and the mathematical foundations of service life monitoring systems.