Objectif The internal surface of HLW glass blocks is an important parameter of all safety calculations for a final repository because the leaching ratio of radioactive nuclides is proportional to the total accessible surface of the waste loaded glass blocks. In addition the extent of phase separation within glass blocks is important in determining their long-term behaviour in the repository environment. It is proposed to use a technique based on Linac driven computerized tomography to determine these crucial properties of HLW and MLW glass blocks. It is further proposed to compare this technique with existing destructive characterization methods. This proposal builds on work carried out in previous projects under the CEC's programme on RADWAS management and disposal. In contract FI2W-CT90-0023 this technique was demonstrated qualitatively. Quantitative measurements were hampered by the effects of beam hardening on image processing. In contract FI2W-CT91-0107 the use of Cerenkov detectors in CT of radioactive waste was shown to significantly reduce beam hardening. It is proposed to combine the use of Cerenkov detectors, more conventional detectors and theoretical modelling of the system to develop a practical non-destructive technique. Modelling of beam hardening in CT will be carried out by AEA Technology. Measurements with both conventional and Cerenkov detectors will be carried out by BAM. As a result of this work a measurement and image processing procedure will be designed by AEA Technology and BAM, optimised to surface area and phase separation determination. This will be used to measure these properties for specimen blocks supplied by CEA. After measurement the blocks will be returned to CEA, opened and subjected to leach tests for comparison. Programme(s) EAEC-NFS 2 - Specific research and training programme in the field of nuclear safety and safeguards, 1994-1998 Thème(s) 030302 - Characterization of waste forms and matrices Appel à propositions Data not available Régime de financement CSC - Cost-sharing contracts Coordinateur United Kingdom Atomic Energy Authority (UKAEA) Contribution de l’UE Aucune donnée Adresse Harwell Laboratory OX11 0RA Didcot Royaume-Uni Voir sur la carte Coût total Aucune donnée Participants (2) Trier par ordre alphabétique Trier par contribution de l’UE Tout développer Tout réduire Bundesanstalt fuer Materialforschung und Materialpruefung Allemagne Contribution de l’UE Aucune donnée Adresse 87,Unter den Eichen 12205 Berlin Voir sur la carte Coût total Aucune donnée Commissariat à l'Energie Atomique France Contribution de l’UE Aucune donnée Adresse Ctr Etudes Vallée du Rhône - CE-VALRHO 30207 Bagnols-sur-Cèze Voir sur la carte Coût total Aucune donnée