WAVELETS AND STATISTICAL TECHNIQUES FOR DATA ANALYSIS IN A MOCK-UP HIGH-LEVEL WASTE STORAGE EXPERIMENT
This work analyzes the physical processes occurring in the Mock-up test of the FEBEX I and II projects. FEBEX I and II is an European research project (1996–2004) led by ENRESA, that has financial support from the European Commission. This experiment is based in two large-scale heating tests ("in-situ" test and "Mock-up" test) simulating a radioactive waste repository, and tries to analyze the thermo-hydro-mechanical (THM) processes that could eventually happen in this kind of repositories.The main objectives of this study have been the following: to identify the physical processes occurring in the Mock-up experiment and to characterize them quantitatively; to understand the nature and consequences of several incidents happening in the Mock-up during the heating phase; and, finally, to analyze the data reliability of the sensors measurements and to predict possible failures.The analysis techniques used in this work are both statistical (time series correlation and spectral analysis, wavelets analysis, matching pursuit analysis) and non-statistical (spatial distribution analysis of data). These methods aim to establish the existing relationships between several data series registered in the experiment, corresponding to the measured parameters, and to characterize on time and frequency the non-stationary response of the series. A better understanding of the main THM processes affecting the engineered barriers used for the isolation of the radioactive waste is then available with the results obtained from those analyses.