Structural evaluation of a reactor building during pressure leak-rate testing for life extension assessment

MARCELO A. CEBALLOS; CARLOS ESTRADA; FEDERICO PINTO; CARLOS A. PRATO

Berlin

Conferencia; SMAR 2019; 2019

As a part of a life extension project, a pressure leak-rate test has been carried out at the Embalse NPP, located in Córdoba (Argentina). Testing consisted of applying a differential pressure of 126 kPa inside the reactor building in order to represent the design basis accident. Both leakage rate and structural deformations were monitored at several locations of the prestressed containment structure in order to evaluate its response with respect to model predictions considering linear elastic response. Given the fact that the testing was performed over several days, when significant thermal fluctuations took place, both internal and external temperatures were recorded before, during, and after the testing. The thermal records were then introduced in a numerical model to evaluate the resulting deformations that were expected to be of the same order as those due to the internal pressure. This paper describes the pressure leak-rate test, the instrumentation used and the results, with particular emphasis on the modeling procedure to account for the rather complex thermal variations that took place during the test, that were to be filtered out in order to assess the response of the building due to the applied pressure.