Development of fundamental and applied researches in the field of machine sciences using strength, safe life, survivability and safety criteria
The stages and results of fundamental and applied research regarding the problems of strength, resource, survivability and technogenic safety carried out at the A. A. Blagonravov Mechanical Engineering Research Institute of the Russian Academy of Sciences throughout a 80-year history are considered. Equations of state and criterion expressions regarding static and dynamic loading, high-cycle and a low-cycle fatigue resistance, high-temperature and low-temperature static and cyclic strength, stress-strain states analysis upon elastic and elastoplastic strain, problems of linear and nonlinear fracture mechanics are derived. The last decades have been marked by the development of basic research on the mechanics of catastrophes, survivability and man-made safety of machines and structures, including the results of complex developments in all the listed areas of strength and resource. The results of studying strength, resource and survivability are the basic components for the mechanics of catastrophes and risks in the technogenic sphere, as well as the new principles and technologies for technogenic objects ensuring their safe operation and prevention on a reasonable scientific basis emergency and catastrophic situations and°r minimize possible damages attributed to them. Diagnostics of the current parameters of the material state and determination of the characteristics of stress-strain states in the most loaded zones of the analyzed technical system is thus a tool for ensuring safe operation conditions. The solution to the problem of assessing the strength and resource in such conditions includes creation of generalized mathematical and physical models of complicated technological, operation and emergency processes in technical systems to analyze conditions of their transition from normal state to emergency or catastrophic states. It is shown that as the analyzed structure passes through admissible to limiting states thus causing the occurrence of failures and subsequent emergency and catastrophic situations, it is necessary to introduce into the regulatory calculations of such states an additional set of defining equations and their parameters characterizing these limiting states. Those calculations are based on the systems of criterion equations, including the parameters of risk, safety and security of the technosphere objects.