[en] This invention concerns the transfer of toxic or radioactive substances between a containment and a flask in which such substances are transported. When toxic or radioactive substances are being transferred, it is important to ensure that such substances cannot escape into the surrounding atmosphere and, preferably, the appliance utilized has to be capable of making a misuse impossible, whether accidental or calculated. The flask to which this invention applies is of the type comprising a flange near an open end which can marry with a sliding blocking component inside the containment to hold and maintain the flask against the wall of the latter. Its open end is aligned with an access opening in the wall of the containment

[en] The vessel contains a mix of several gases. This gas mix is made to flow through a closed circuit whilst maintaining a constant relative pressure inside the vessel. This closed circuit includes a gas analyzing apparatus which makes it possible to measure the amount of one of the gases in the mix, this gas being called ''reference gas'', then at a preset frequency the determination is made again in order to determine the change in this amount over time. Application to the testing of leak tightness

[en] This invention concerns the transfer of toxic or radioactive substances between a containment and a flask in which such substances are transported. When toxic or radioactive substances are being transferred, it is important to ensure that such substances cannot excape into the surrounding atmosphere and, preferably, the appliance utilized has to be capable of making a misuse impossible, whether accidental or calculated. The flask to which this invention applies is of the type comprising lugs, near its open ends, which act in combination with a groove made around an access opening to hold and maintain the flask in position against the wall of the containment, so that its open end is aligned with an access opening provided in the containment wall

[en] The invention aims at the development of bushing means for passing electric wires through containment shells in such a way that air-tightness and its continuous monitoring during operation is ensured

No abstract available

[en] There are arguments in favour of passive safeguards, acting in case of accidents without external energy, external cooling sources, or sophisticated automatisms, and limiting the extension of the accidents without early human intervention. In this respect, a discussion is first presented on concrete leaktightness, which seems achievable. The paper proposes however a new concept of wall and raft, with the aim of obtaining a very good containment with ordinary concrete. (orig.)

No abstract available

[en] Containment structures for nuclear power plants have long been designed for static internal pressure. However, since the Three Mile Island accident there has been heightened interest in the behavior of containments under conditions beyond design, particularly the actual, in-place resistance of containments to static internal pressure. Probabilistic methods are being applied to both the loading and resistance quantities so public risk can be accurately assessed. In this paper, a reliability assessment of a steel containment strength under uniform internal pressure is summarized. Typically the containment vessel is a stiffened shell structure. Failure modes for this type of structure are identified as general, inter-ring and panel failure. Simplified methods to predict the resistance of the vessel under internal pressure are presented. The Advanced First Order Second Moment technique is used in conjunction with the simplified methods to construct the cumulative distribution of the containment resistance as a function of pressure. Uncertainty of the basic variables which affects the containment resistance are propagated through the analysis to evaluate the total uncertainty of the system. The resulting distribution considering all possible failure modes is given for a typical Mark III steel containment. Fragility curves for the containment at 95% and 5% certainty are also given

[en] The invention described discloses a biological shield for a nuclear reactor such as a pressurized-water reactor and the like. The biological shield surrounds the reactor pressure vessel and is made of concrete. The shield includes two concentric shield parts and a cooling medium is conducted through a gap conjointly defined by the shield parts

[en] The present paper aims at specifying the different basic data that the designer of a containment shell has to specify to the manufacturer of the said shell to obtain the desired characteristics. This analyse, for a future installation, has to point out the essential points of its design. The basic data corresponding to the actual needs of the planned installation have to be specified for the manufacturers can propose technological responses coherent and fitted to inherent risks to these ones. This analyse has to examine the means which have to be foreseen for the exploitation, as also the precisions concerning the handled products, the internal conditions of the shell, the external conditions. This guide aims at leading to a realization corresponding to the needs, to a safe exploitation, rational and economic while making easy a futur decommissioning of the installation. The present paper applies to shells used in nuclear industries for works on radioactive products, on dangerous or toxic products, on material needing a shield with regard to the environment, or works needing a sterile medium