Local Damage Assessment of Metal Barriers under Turbine Missile Impacts

Abstract

Turbine missiles resulting from the failure of rotary machines in nuclear-power plants could cause severe damages and endanger public safety. This paper presents the current state of the art on models and methodologies for predicting the magnitude of damages and the possibility of the missile leaving the casing structure. Eight empirical methods for the perforation of steel by rigid missiles were collected and analyzed using over 30 test data from experimental works of the past two decades. Based upon the analyses, several modifications of the empirical and semiempirical formulas are proposed to evaluate the problem of containment and to better reflect the amount of damage resulting from turbine missile impact. The modified formulas are shown to be accurate for over 90% of the test results. It was also found that use of an equivalent missile diameter was helpful in accounting for the piercing impacts in the experimental works. It further reduced the nonconservative nature of the predictions.