Patent Number: 048511846
Section: summary

The invention relates to a building made from concrete walls, in particular for nuclear plants, which encloses plant components in order to protect them from external influences. The concrete walls are typically made of steel-reinforced concrete and are constructed, at least in the regions that perform the protection functions, in such way that they can withstand the outside influences for which they are designed, such as the impact of an airplane crashing into them. A so-called secondary shielding of a nuclear power plant, for instance, is constructed for this purpose in the form of a concrete containment which is up to 2 meters thick. Naturally, the concrete is reinforced. German Published, Prosecuted Applications DE-AS Nos. 10 52 095 and 12 99 404 as well as European Pat. No. 0 009 654 disclose buildings which are constructed differently and are not able to enclose comparably large components in such a manner as to protect them from destruction. It is accordingly an object of the invention to provide a building made from concrete walls, in particular for nuclear plants, which overcomes the hereinafore-mentioned disadvantages of the heretofore-known devices of this general type and which minimizes the concussions that are to be expected in the case of a pulsed load (with a special case being an aircraft impact). As a consequence, greater safety of the components and systems from external influences is to be obtained at comparable expense. With the foregoing and other objects in view there is provided, in accordance with the invention, a building, especially a nuclear plant, comprising concrete walls enclosing components, such as plant components as a protection against external action, the concrete walls having exposed locations and the concrete walls having double-layered regions at the exposed locations with double layers defining hollow spaces therebetween, being optionally filled with a damping material. The hollow spaces can also be provided with an additional thin-walled linings. In accordance with again another feature of the invention, the double layers of the prefabricated building elements include outer shells having shapes and dimensions forming means for highly plastically deforming the outer shells with energy dissipation upon the occurrence of local pulsed loads. According to the invention, external action is no longer absorbed rigidly but instead is absorbed resiliently at exposed points, with an intentional plasticizing and with the maximum possible dissipation of energy. In this way the used load to be absorbed is distributed over time, so that impact strains lessen the forces locally induced into the structure. This is also the prerequisite for reducing the loads on the components housed in the building by means of induced forces of acceleration, both in terms of static safety and in terms of the strains to be expected The invention is thus distinguished from the prior art described in German Published, Prosecuted Applications DE-AS Nos. 10 52 095 and 12 99 404 as well as European Pat. No. 0 009 654, in which buildings are constructed differently and are not in a position to enclose comparably large components in such a manner as to protect them from destruction. With the invention, it also becomes less necessary to provide cost-intensive proof of functional conditions of components and buildings strained by shock-induced concussions. This is particularly true for all of the electrical wiring and plumbing components. Until now, the ability of these systems to function was documented for a frequency range of up to approximately 35 Hz, like that to be expected in earthquakes, for example. The requirement now being made for documenting functional ability even at high acceleration values, in the frequency range up to 80 Hz, which appears possible particularly in the case of aircraft impact, is largely obviated by the invention, because of the aforementioned reduction of accelerations. In accordance with another feature of the invention, there are provided other wall regions neighboring the double-layered regions, the double-layered regions having outer surfaces protruding beyond the other wall regions. This enables a more comprehensive protection. This construction also makes it possible to keep the same interior capacity of the buildings, despite their double-layered structure, which is therefore thicker, at some points. In accordance with a further feature of the invention, the double-layered regions are in the form of rounded regions at edges and corners of the building. This makes it possible to round the corners there so that the load-bearing capability of the shells can be exploited to improve energy distribution. In accordance with an added feature of the invention, the double-layered regions are disposed in the vicinity of load-bearing ceilings located within the building. In this way, the aforementioned induction of forces brought to bear from the outside into the interior of the buildings is prevented in a particularly favorable manner. In accordance with an additional feature of the invention, the double layers include an outer shell formed of concrete having a filamentary filler material. The outer layer of the double-layered wall regions can also be steel-fiber-reinforced concrete with corresponding armoring. A tough, energy-dissipating, resilient structure can thus be attained, which makes it possible to fully exploit both the plastic behavior of the steel-fiber-reinforced concrete as well as the damping effect of the lined hollow space. In accordance with yet another feature of the invention, the double layers are in the form of shells, and each of the hollow spaces has a width substantially equal to the thickness of one of the plasticizing shells. On the other hand, the thickness can also be optimized and determined by the filling material. In accordance with a concomitant feature of the invention, each of the double-layered wall regions is in the form of a prefabricated building element fastened to the outside of one of the concrete walls. This is an embodiment that is especially promising economically, and is also suitable for retrofitting. In this connection, the term "fastened" means that in normal operation the prefabricated building elements exhibit the necessary static safety. This can be provided intrinsically by the weight with which the wall elements rest on the top of a concrete wall. Other features which are considered as characteristic for the invention are set forth in the appended claims. Although the invention is illustrated and described herein as embodied in a building made from concrete walls, in particular for nuclear plants, it is nevertheless not intended to be limited to the details shown, since various modifications and structural changes may be made therein without departing from the spirit of the invention and within the scope and range of equivalents of the claims.