[en] Short communication. 4 refs

No abstract available

[en] Transport of uranium hexafluoride during the different phases of the fuel cycle is carried out using containers of various types that must meet the safety requirements provided for in the specific international regulations for this area. Qualification of the behavior of the 30B cylinder and its respective overpack under reference accident conditions for the purpose of design and utilization of such containers is currently a subject of interest on an international level, since it is being widely used in a number of countries. To contribute to this qualification process, a relatively complex research program was defined and developed, including, among other things, drop tests from 9 m on to an unyielding target, drop tests from a height of 1 m on to a cylindrical bar, and thermal tests in a furnace, all of which were carried out on two complete specimens of the same container with a simulated load. For analysis of the damage a series of leak tests and a water immersion test were developed to analyze the damage to the two specimens mentioned above and to a container of reduced dimensions designed for this purpose and equipped to reproduce conditions similar to the real conditions inside the container under investigation. Evaluation of the heat exchange conditions that could exist in the container given real contents of uranium hexafluoride was also conducted using a series of calculations carried out with the computer code TRUMP. The results of the different types of experiments and calculations performed and presented in detail in the present study have made it possible to draw useful conclusions for practical evaluation of the reliability of the container under investigation, also in view of the intended goal of container qualification as per the existing regulations for transport of radioactive material. 21 refs., 44 figs., 3 tabs

[en] A simple scaling formula for impact load calculation is presented and the result of a simple calculation model is discussed. Maximum impact loads are calculated for various aircraft: Phantom-4, Learjet, Cessna-210, Boeing-707 and Boeing-747. It can be concluded that roughly 2 meters of wall are sufficient to prevent the perforation even in the case of the Boeing-747. The acceptability of a lower thickness wall can also be discussed. The problem which remains to be solved is the one of the strong shaking of the structures and of components. In order to solve this problem, a specific design solution is suggested: it essentially consists in assuring to most exposed parts of structures an adequate degree of deformability. The decoupling of the cupola from the rest of the building could be obtained by the introduction of elastic joints and of viscous dampers at the base of the cupola

No abstract available

[en] The results of the test data elaboration, besides other considerations, provide: an inside view of the real deformation mechanism of this type of shock absorber; validation of the design calculation performed by means of FE codes; verification of the possibility of using the model test data for the prototype, on the basis of statistical checks and dimensional analysis; and a test of the actual structure capability to limit the dynamic load transmitted to the foreseen package body. 4 references

No abstract available

[en] This article gives an overview on nuclear engineering research at the universitites of Bologna, Palermo, Pisa, Rome and the polytechnics of Milan and Turin

[en] ENEA is studying, with the collaboration of the DCMN of the Pisa University, a new packaging to collect wastes in various facilities while proceeding to find a final disposal. Following a survey on the wastes that could be transported in the future, it was agreed to design a packaging able to contain an industrial drum, with a maximum capacity of 220 litres and a total weight less than 4000 N, previously filled with solid wastes in bulk or in a solid binding material. The packaging, to be approved as a Type B in agreement with the IAEA Regulations, will be useful to transport not only radioactive wastes but any kind of dangerous goods and also those not in agreement with the UNO Regulations. The 1/2 scale model of the packaging is formed by two concentric vessels of mild steel obtained by welding commercial shells to cylindrical walls and joined through a flange. The new packaging under development presents features that seem to be proper for its envisaged waste collection main use such as construction simplicity, relatively low cost, time and use endurance, low maintenance requirements. The design analysis and testing program ongoing at present allowed for the preliminary definition of the packaging geometry and confirmed the necessity of further investigations in some key areas as the determination of actual behaviour of the silicon foam, used as energy absorbing/thermal insulating material, in the specific conditions of interest. (J.P.N.)

[en] The main results of the elaboration of the test data sets, collected during the development of a research program carried out by the Dipartimento di Costruzioni Meccaniche e Nucleari of Universita di Pisa, for the study and the characterization of a shell type shock absorber for a LWR spent fuel cask at present under study in Italy, are discussed. The test program included several impact test series on reduced scale models for practical and economical reasons, as the prototype weight will be over 64,000 kg. The experimental data were elaborated against the results of a dimensional analysis of the structure dynamic deformation problem. This analysis indicates, in synthesis, for the acceleration an inverse and for deformation a direct proportionality to the scale factor. Actually the values of the adimensional monomials, derived from the analysis and calculated by means of the experimental values of variables such as acceleration and deformation, are in a fair mutual agreement and seem to form a statistically significative set of data. Also the overall efficiency of the impact limiter was confirmed by the relatively low expected acceleration values for the prototype. (orig.)