WIT Press


Numerical Characterization Of Vermiculite-concrete Mixture Used As A Shock Absorber For A Nuclear Waste Container

Price

Free (open access)

Volume

98

Pages

10

Page Range

127 - 136

Published

2008

Size

945 kb

Paper DOI

10.2495/SU080131

Copyright

WIT Press

Author(s)

N. Zaccari, M. Torrigiani & G. Forasassi

Abstract

This paper deals with numerical and experimental analyses of a type B(U) package for radioactive waste transport. 9 m vertical free drop tests, performed on reduced scale models, are described and analysed. The experimental results are compared with numerical simulations performed with FEM computer codes, considering reduced scale models as well as the prototype. Firstly the paper deals with the numerical characterization of vermiculite-concrete mixture used as a shock absorber in this kind of package by considering the literature data and the experimental test performed at Pisa University. Moreover, the paper shows the results of a similitude analysis which permits one to extrapolate the data obtained by means of the reduced scale models to the prototype. Small errors were obtained considering models of large scale (1:2,5) and medium scale (1:4) in comparison with the smaller scale results. Keywords: vermiculite, shock absorber, dimensional analysis, packaging, radioactive waste. 1 Introduction Radioactive wastes are shipped in casks designed to prevent the release of the radioactive material to the environment in normal as well as accidental conditions. The latter are established by the relevant rules (IAEA Recommendations) by means of a series of experimental tests. In Italy ENEA has studied for many years, in collaboration with University of Pisa, several containers and packages to collect many types of radioactive sources of different radionuclides no longer used in hospitals around the country. To improve the

Keywords

vermiculite, shock absorber, dimensional analysis, packaging, radioactive waste.