Non-destructive Evaluation of Containment Walls in Nuclear Power Plants

V. Garnier (1) , C. Payan (1) , M. Lott (1) , Narintsoa Ranaivomanana (2) , Jean-Paul Balayssac (2) , Jérôme Verdier (2) , E. Larose (3) , Y. Zhang (3) , J. Saliba , A. Boniface , Z. M. Sbartai , Bogdan Piwakowski (4, 5, 6) , Charles Ciccarone (6) , H. Hafid , J. M. Henault , F. Ouvrier Buffet (1)

1 LMA - Laboratoire de Mécanique et d'Acoustique [Marseille]
2 LMDC - Laboratoire Matériaux et Durabilité des constructions
3 ISTerre - Institut des Sciences de la Terre
4 IEMN-DOAE - Institut d’Électronique, de Microélectronique et de Nanotechnologie - Département Opto-Acousto-Électronique - UMR 8520
5 TPIA - IEMN - Transduction, Propagation et Imagerie Acoustique - IEMN
6 IEMN - Institut d’Électronique, de Microélectronique et de Nanotechnologie - UMR 8520

Two functions are regularly tested on containment walls in order to anticipate a possible accident. The first is mechanical to resist a possible internal over-pressure and the second is to prevent leakage. The AAPR reference accident is the rupture of a pipe in the primary circuit of a nuclear plant. In this case, the pressure and temperature can reach 5 bar and 180 C in 20 seconds. The national project Non-destructive testing of the containment structures of nuclear plants' aims at studying the non-destructive techniques capable to evaluate the concrete properties and its damaging and cracks. This 4-year-project is segmented into two parts. The first consists in developing and selecting the most relevant NDEs in the laboratory to reach these goals. These evaluations are developed in conditions representing the real conditions of the stresses generated during ten-yearly visits of the plants or those related to an accident. The second part consists in applying the selected techniques to two containment structures under pressure. The first structure is proposed by ONERA and the second is a mockup of a containment wall on a 1/3 scale made by EDF within the VeRCoRs project. Communication is focused on the part of the project that concerns the damage and crack process characterization by means of NDT. The tests are done in 3 or 4 points bending in order to study the cracks' generation, their propagation, as well as their opening and closing. The main ultrasonic techniques developed concern linear or non-linear acoustic: acoustic emission [1], Locadiff [2], energy diffusion, surface wave's velocity and attenuation, DAET [3]. The recorded data contribute to providing the mapping of the investigated parameters, either in volume, in surface or globally. Digital image correlation is an important additional asset to validate the coherence of the data. The spatial normalization of the data in the specimen space allows proposing algorithms on the combination of the experimental data. The tests results are presented and they show the capacity and the limits of the evaluation of the volume, surface or global data. A data fusion procedure is associated with these results.

Domaines: Sciences de l'ingénieur [physics]; Physique [physics]; Informatique [cs]

V. Garnier, C. Payan, M. Lott, Narintsoa Ranaivomanana, Jean-Paul Balayssac, et al.. Non-destructive Evaluation of Containment Walls in Nuclear Power Plants. 43rd Review of Progress in Quantitative Nondestructive Evaluation, Jul 2016, Atlanta, United States. pp.UNSP 080018--1, ⟨10.1063/1.4974643⟩. ⟨hal-01847558⟩