Vulnerability Analysis of Pipelines and Equipment of the Existing NPP Power Units with VVER-1000 under Vibrations Caused by the Aircraft Crash

Abstract

Low-frequency dynamic loads from earthquakes were taken into account in the design of the equipment and pipelines of the existing nuclear power plants. Therefore, in the case of an aircraft crash impact on a nuclear reactor containment, exciting intense high-frequency vibrations of the building, the reliability of the nuclear power plant cannot be guaranteed without the failure risk assessment of objects that are involved in the safe shutdown.
 The paper suggests a method of the failure risk assessment using the concept of the ultimate resistance of pipelines and equipment of nuclear power plants to vibrations typical for the “aircraft crash” emergency design situation. The ultimate resistance is defined by the value of the load impulse, the application of which results in the probability of failure of the considered pipeline or equipment of 0.01 taking into account that it performs functions to provide 0.50 safety.