JP5943583B2 - Reinforced structure of spent fuel rack - Google Patents

Description

  The present invention relates to a spent fuel rack reinforcing structure for temporarily storing spent fuel rods taken out from a nuclear reactor.

  One of the nuclear power plants is a pressurized water reactor. In this pressurized water reactor, light water is used as a reactor coolant and a neutron moderator, and high-temperature and high-pressure water that does not boil throughout the primary system is used. Water is sent to a steam generator to generate steam by heat exchange, and this steam is sent to a turbine generator to generate electricity.

  In such a nuclear power plant, a spent fuel pool for temporarily storing spent fuel rods taken out from the pressurized water reactor is provided in the reactor building. A spent fuel rack that supports the spent fuel rods in an upright state is installed. As such a spent fuel rack, there exists a thing described in the following patent document 1, for example. The fuel rack upper support structure described in Patent Document 1 includes an integrated spacer that supports the upper portion of the fuel rack, and the integrated spacer is provided between the fuel racks and between the fuel rack and the fuel pool wall. The spacer is composed of a tapered spacer to be filled and a frame for integrally joining the spacers, and is installed on the upper part of the fuel rack by its own weight.

JP 2000-275385 A

  The conventional fuel rack upper support structure described above requires a tapered spacer inserted between the fuel racks and between the fuel rack and the fuel pool wall. That is, many taper spacers must be used, and the structure becomes complicated. Also, if there are variations in the gap between the fuel racks or the gap between the fuel rack and the fuel pool wall, the tapered spacers will not be properly inserted into the gap, and the rack will have sufficient earthquake resistance. It becomes difficult.

  SUMMARY OF THE INVENTION The present invention solves the above-described problems, and can reinforce spent fuel racks that can appropriately improve the earthquake resistance of spent fuel racks while simplifying the structure and reducing costs. The purpose is to provide a structure.

  In order to achieve the above object, the spent fuel rack reinforcing structure of the present invention has a plurality of cells into which spent fuel can be inserted from above along the vertical direction, and the lower part is located at the bottom of the spent fuel pool. In the fixed spent fuel rack, a damper device is provided between a wall surface of the spent fuel pool and a side surface of the spent fuel rack.

  Therefore, in the spent fuel rack, the horizontal swing is suppressed by the damper device, so that the earthquake resistance of the spent fuel rack can be improved, and the structure can be simplified and the cost can be reduced. .

  In the reinforcing structure for a spent fuel rack according to the present invention, the damper device is provided between a wall surface of the spent fuel pool and an upper side surface of the spent fuel rack, and is provided on four sides of the spent fuel rack. It is characterized by that.

  Therefore, the spent fuel rack has its lower part fixed to the bottom of the spent fuel pool and its upper part supported by the damper device on all four sides, thereby suppressing the horizontal shaking of the spent fuel rack and improving the earthquake resistance. can do.

  In the spent fuel rack reinforcing structure according to the present invention, the damper device functions by movement of a fluid filled therein.

  Therefore, in the spent fuel rack, the horizontal vibration is suppressed by the movement of the fluid filled in the damper device, so that the earthquake resistance of the spent fuel rack can be improved.

  In the spent fuel rack reinforcing structure according to the present invention, the damper device has a piston mechanism immersed in the cooling water of the spent fuel pool, and the piston mechanism can move the piston with a predetermined gap in the cylinder. It is characterized by being supported by.

  Therefore, in the spent fuel rack, when horizontal shaking occurs, the horizontal shaking is suppressed by the orifice effect in which the cooling water passes through the gap between the cylinder and the piston when the piston moves, and the spent fuel pool is cooled. By using water, the structure can be simplified and the cost can be reduced.

  In the reinforcing structure for a spent fuel rack according to the present invention, the damper device functions by movement of a dilatant fluid filled therein.

  Therefore, by using the dilatant fluid as the fluid that suppresses the horizontal shaking of the spent fuel rack, it is possible to effectively improve the earthquake resistance of the spent fuel rack.

  In the reinforcing structure for a spent fuel rack according to the present invention, the damper device has a piston mechanism, and the piston mechanism is filled with the dilatant fluid in a cylinder, and the piston in the dilatant fluid in the cylinder. Is characterized by being configured to be movably supported.

  Therefore, in the spent fuel rack, when the horizontal shaking occurs, the piston moves, the viscosity of the dilatant fluid increases, and the movement of the piston is restricted, thereby suppressing the horizontal shaking. Simplification and cost reduction can be achieved.

  In the structure for reinforcing a spent fuel rack according to the present invention, the damper device has a pair of magnets in which the same pole portions are arranged to face each other at a predetermined interval.

  Therefore, the spent fuel rack can be simplified in structure because the horizontal swing is suppressed by the repulsive force of the pair of magnets.

  In the structure for reinforcing a spent fuel rack according to the present invention, the damper device has a bag-like member that increases the internal pressure when the seismic intensity exceeds a predetermined seismic intensity.

  Therefore, when the seismic intensity exceeds the predetermined seismic intensity and the horizontal shaking occurs, the spent fuel rack increases the internal pressure of the bag-like member, which suppresses the horizontal shaking, and improves the seismic resistance of the spent fuel rack. Can be improved.

  According to the reinforcing structure of the spent fuel rack of the present invention, since the damper device is provided between the wall surface of the spent fuel pool and the side surface of the spent fuel rack, the earthquake resistance of the spent fuel rack can be improved. At the same time, the structure can be simplified and the cost can be reduced.

FIG. 1 is a plan view of a spent fuel pool showing a spent fuel rack reinforcing structure according to Embodiment 1 of the present invention. FIG. 2 is a longitudinal sectional view of a spent fuel pool showing a reinforcing structure of a spent fuel rack according to the first embodiment. FIG. 3 is a schematic view of the damper device. FIG. 4 is a schematic configuration diagram illustrating a nuclear power plant. FIG. 5 is a schematic view showing a reactor containment vessel. FIG. 6 is a plan view of the spent fuel pool showing the reinforcing structure of the spent fuel rack according to the second embodiment of the present invention. FIG. 7 is a vertical cross-sectional view of a spent fuel pool showing a reinforcing structure of a spent fuel rack according to the second embodiment. FIG. 8 is a schematic view showing a connection structure between the spent fuel rack and the piston portion. FIG. 9 is a schematic view illustrating a modification of the spent fuel rack reinforcing structure according to the second embodiment. FIG. 10 is a plan view of a spent fuel pool showing a spent fuel rack reinforcing structure according to Embodiment 3 of the present invention. FIG. 11 is a longitudinal sectional view of a spent fuel pool showing a reinforcing structure of a spent fuel rack according to the third embodiment. FIG. 12 is a plan view of a spent fuel pool showing a modified example of the spent fuel rack reinforcing structure according to the third embodiment. FIG. 13 is a longitudinal sectional view of a spent fuel pool showing a reinforcement structure for a spent fuel rack according to Embodiment 4 of the present invention. FIG. 14 is a longitudinal sectional view of a spent fuel pool showing a reinforcement structure for a spent fuel rack according to Embodiment 5 of the present invention.

  Exemplary embodiments of a spent fuel rack reinforcing structure according to the present invention will be explained below in detail with reference to the accompanying drawings. In addition, this invention is not limited by this Example, Moreover, when there exists multiple Example, what comprises combining each Example is also included.

  FIG. 1 is a plan view of a spent fuel pool representing a spent fuel rack reinforcing structure according to a first embodiment of the present invention, and FIG. 2 is a spent fuel pool representing a spent fuel rack reinforcing structure according to the first embodiment. FIG. 3 is a schematic diagram of a damper device, FIG. 4 is a schematic configuration diagram showing a nuclear power plant, and FIG. 5 is a schematic diagram showing a nuclear reactor containment vessel.

  The nuclear reactor applied to the nuclear power plant of Example 1 uses light water as a reactor coolant and a neutron moderator to produce high-temperature and high-pressure water that does not boil over the entire primary system, and sends this high-temperature and high-pressure water to a steam generator. This is a pressurized water reactor (PWR) that generates steam by heat exchange and sends the steam to a turbine generator to generate electricity.

  That is, in the nuclear power plant having this pressurized water reactor, as shown in FIG. 4, the pressurized water reactor 12 and the steam generator 13 are stored in the reactor containment vessel 11. The furnace 12 and the steam generator 13 are connected via cooling water pipes 14 and 15, a pressurizer 16 is provided in the cooling water pipe 14, and a cooling water pump 17 is provided in the cooling water pipe 15. In this case, light water is used as the moderator and the primary cooling water, and the primary cooling system is controlled by the pressurizer 16 so as to maintain a high pressure state of about 160 atm in order to suppress boiling of the primary cooling water in the core. Yes. Therefore, in the pressurized water reactor 12, light water is heated as primary cooling water by low-enriched uranium or MOX as fuel, and the high-temperature primary cooling water is maintained at a predetermined high pressure by the pressurizer 16. To the steam generator 13. In the steam generator 13, heat exchange is performed between the high-pressure and high-temperature primary cooling water and the secondary cooling water, and the cooled primary cooling water is returned to the pressurized water reactor 12 through the cooling water pipe 15.

  The steam generator 13 is connected to a turbine 18 and a condenser 19 provided outside the reactor containment vessel 11 through cooling water pipes 20 and 21, and a water supply pump 22 is provided in the cooling water pipe 21. ing. Further, a generator 23 is connected to the turbine 18, and a condenser pipe 19 is connected to a water intake pipe 24 and a drain pipe 25 for supplying and discharging cooling water (for example, seawater). Accordingly, the steam generated by exchanging heat with the high-pressure and high-temperature primary cooling water in the steam generator 13 is sent to the turbine 18 through the cooling water pipe 20, and the turbine 18 is driven by this steam to generate the generator 23. To generate electricity. The steam that has driven the turbine 18 is cooled by the condenser 19, and then returned to the steam generator 13 through the cooling water pipe 21.

  As shown in FIG. 5, the nuclear reactor power plant containment vessel 11 of the nuclear power plant configured as described above accommodates the above-described pressurized water reactor 12, the steam generator 13, the pressurizer 16, and the like. On the other hand, a fuel handling building 30 is installed adjacent to the reactor containment vessel 11, and a spent fuel pool 31 is provided in the fuel handling building 30, and a spent fuel rack is provided inside the spent fuel pool 31. 32 is installed. The spent fuel rack 32 temporarily stores spent fuel (fuel rods) used in the pressurized water reactor 12, and the spent fuel stored in the spent fuel rack 32 is: The spent fuel pool 31 is filled and can be cooled by circulating cooling water.

  As shown in FIGS. 1 and 2, the spent fuel rack 32 has a square tube shape with a bottom, an upper portion is opened, and a plurality of square tubes are arranged at equal intervals inside and fixed by welding. Thus, a plurality of cells 32a into which spent fuel can be inserted from above along the vertical direction are formed. The cells 32 a are adjacent to each other adjacent to the lower part in the spent fuel rack 32.

  The spent fuel pool 31 has a predetermined size, a base frame 33 is fixed to the bottom 31 a, and a spent fuel rack 32 is fixed on the base frame 33. Six spent fuel racks 32 are arranged on the base frame 33 at a center in the spent fuel pool 31 with a predetermined gap between each other, and a predetermined gap is provided between the spent fuel pool 31 and the wall surface of the spent fuel pool 31. It is arranged with. The spent fuel pool 31 is filled with cooling water so that the entire spent fuel rack 32 is immersed therein.

  The spent fuel rack reinforcing structure according to the first embodiment is configured by providing a damper device 41 between a wall surface 31b of the spent fuel pool 31 and a side surface 32b of the spent fuel rack 32.

  As described above, six spent fuel racks 32 are arranged on the base frame 33 of the spent fuel pool 31 at a predetermined interval. The damper device 41 is provided between the wall surface 31 b of the spent fuel pool 31 and the upper side surface 32 b of the spent fuel rack 32 and on four sides of the six spent fuel racks 32.

  Each damper device 41 functions by movement of a fluid (cooling water) filled therein. That is, the damper device 41 has a piston mechanism immersed in the cooling water of the spent fuel pool 31, and this piston mechanism is configured such that the piston is movably supported within the cylinder with a predetermined gap.

  In the damper device 41, the cylinder 42 has a cylindrical shape with one open and the other closed, and the closed end is connected to the wall surface 31 b of the spent fuel pool 31 by a connecting rod 43. The piston 44 has an outer diameter that is slightly smaller than the inner diameter of the cylinder 42, and is movably supported inside the cylinder 42 with a predetermined gap S. One end surface of the piston 44 is a side surface of the spent fuel rack 32 by a connecting rod 45. 32b. In this case, the cylinder 42 and the piston 44 constitute a piston mechanism, and a predetermined gap S between the outer peripheral surface of the piston 44 and the inner peripheral surface of the cylinder 42 functions as an orifice.

  In the present embodiment, a plurality of damper devices 41 are provided around the six spent fuel racks 32 fixed in the spent fuel pool 31, and adjacent spent fuel racks 32 are not shown in the figure. It is good to connect with a member. Further, although the damper device 41 is provided between the wall surface 31b of the spent fuel pool 31 and the side surface 32b of the spent fuel rack 32, a damper device may be provided between the adjacent spent fuel racks 32.

  Accordingly, as shown in FIGS. 1 and 2, the plurality of spent fuel racks 32 are fixed on the base frame 33 of the spent fuel pool 31 with a predetermined gap, and the side surfaces 32b on the outer peripheral side are respectively It is supported on the wall surface 31 b of the spent fuel pool 31 via the damper device 41. At this time, if horizontal shaking occurs due to an earthquake or the like, the horizontal shaking of each spent fuel rack 32 is suppressed by each damper device 41.

  That is, as shown in FIG. 3, when the upper part of the spent fuel rack 32 swings horizontally, the piston 44 is pressed or pulled by the damper device 41 via the connecting rod 45. Then, the piston 44 tries to move with respect to the cylinder 42 fixed to the spent fuel pool 31 side via the connecting rod 43. Here, since the damper device 41 is immersed in the cooling water in the spent fuel pool 31, the cooling water also enters the cylinder 42. Therefore, when the piston 44 moves in the cylinder 42, the cooling water passes through the predetermined gap S between the outer peripheral surface of the piston 44 and the inner peripheral surface of the cylinder 42, and the moving resistance of the piston 44 increases and the moving speed increases. Is reduced, the vibration (vibration) of the spent fuel rack 32 is attenuated.

  As described above, the spent fuel rack reinforcing structure according to the first embodiment has the plurality of cells 32a into which the spent fuel can be inserted from above along the vertical direction, and the lower portion is the bottom of the spent fuel pool 31. In the spent fuel rack 32 fixed to 31 a, a damper device 41 is provided between the wall surface 31 b of the spent fuel pool 31 and the side surface 32 b of the spent fuel rack 32.

  Therefore, the spent fuel rack 32 can improve the earthquake resistance of the spent fuel rack 32 by suppressing the horizontal shaking by the damper device 41, and the spent fuel rack 32 can be improved only by providing the damper device 41. By suppressing the vibration of 32, the structure can be simplified and the cost can be reduced.

  Further, in the spent fuel rack reinforcing structure of the first embodiment, the damper device 41 is disposed between the wall surface 31b of the spent fuel pool 31 and the side surface 32b of the spent fuel rack 32, and includes a plurality of spent fuel racks 32. It is provided on all four sides. Accordingly, the spent fuel rack 32 has its lower part fixed to the bottom of the spent fuel pool 31 and its upper part supported by the damper device 41 on all sides, so that the horizontal shaking of the spent fuel rack 32 is appropriately suppressed, Seismic resistance can be improved.

  In the reinforcing structure of the spent fuel rack according to the first embodiment, the damper device 41 has a piston mechanism that is immersed in the cooling water of the spent fuel pool 31, and the piston mechanism has a predetermined gap S in the cylinder 42. The piston 44 is movably supported so as to function by the movement of the cooling water filled therein. Therefore, in the spent fuel rack 32, when horizontal shaking occurs, the horizontal shaking is suppressed by the orifice effect when the cooling water passes through the gap S between the cylinder 42 and the piston 44 when the piston 44 moves. Therefore, the horizontal shaking of the spent fuel rack 32 can be suppressed appropriately, and the structure can be simplified and the cost can be reduced by using the cooling water of the spent fuel pool 31.

  FIG. 6 is a plan view of a spent fuel pool representing a spent fuel rack reinforcing structure according to a second embodiment of the present invention, and FIG. 7 is a spent fuel pool representing a spent fuel rack reinforcing structure according to the second embodiment. FIG. 8 is a schematic diagram showing a connection structure between a spent fuel rack and a piston portion, and FIG. 9 is a schematic diagram showing a modification of the reinforcing structure of the spent fuel rack according to the second embodiment. In addition, the same code | symbol is attached | subjected to the member which has the function similar to the Example mentioned above, and detailed description is abbreviate | omitted.

  As shown in FIGS. 6 and 7, the reinforcing structure of the spent fuel rack according to the second embodiment is provided with a damper device 51 between the wall surface 31 b of the spent fuel pool 31 and the side surface 32 b of the spent fuel rack 32. Configured. In this case, the damper device 51 is provided on all sides of the spent fuel rack 32.

  Each damper device 51 functions by movement of a fluid (dilatant fluid) filled therein. In other words, the damper device 51 has a piston mechanism that is isolated (waterproofed) from the cooling water of the spent fuel pool 31. The piston mechanism is filled with a dilatant fluid in the cylinder, and the dilatant in the cylinder. The piston is configured to be movably supported in the fluid.

  In the damper device 51, a casing (cylinder) 52 is fixed to each wall surface 31b of the spent fuel pool 31, and a dilatant fluid (shear hardening fluid) is filled therein. The piston 53 is movable in the casing 52 and is connected to the side surface 32 b of the spent fuel rack 32 by a connecting rod 54. That is, as shown in FIG. 8, the connecting rod 54 has a piston 53 fixed to one end thereof and an inverted U-shaped connecting bracket 55 fixed to the other end thereof. The fuel rack 32 is fixed by fixing bolts 56 so as to sandwich the side surface 32b. In this case, the casing 52 and the piston 53 constitute a piston mechanism.

  Accordingly, as shown in FIGS. 6 and 7, the spent fuel rack 32 is fixed to the bottom 31 a of the spent fuel pool 31, and each side surface 32 b on the outer peripheral side is respectively used fuel via the damper device 51. It is supported by the wall surface 31b of the pool 31. At this time, when horizontal shaking occurs due to an earthquake or the like, the horizontal shaking of the spent fuel rack 32 is suppressed by each damper device 51.

  That is, when the upper part of the spent fuel rack 32 is shaken horizontally, the piston 53 is pressed or pulled by the damper device 51 via the connecting rod 54. Then, the piston 53 tries to move with respect to the casing 52 fixed to the spent fuel pool 31 side. Here, since the dilatant fluid is hermetically filled in the casing 52, when the piston 53 moves in the casing 52, the viscosity of the dilatant fluid increases, the movement resistance of the piston 53 increases, and the movement speed decreases. As a result, the vibration (vibration) of the spent fuel rack 32 is attenuated.

  Note that the dilatant fluid sealing and filling method is not limited to this configuration. For example, as shown in FIG. 9, the damper device 61 is connected to the support plate 62 fixed to each wall surface 31 b of the spent fuel pool 31 and the side surface 32 b of the spent fuel rack 32 via a connecting rod 63. Between the piston 64, a dilatant fluid is filled and a container 65 that can be expanded and contracted is arranged. Therefore, when the spent fuel rack 32 swings horizontally, the piston 64 is pressed or pulled, and the container 65 filled with the dilatant fluid is pressed or pulled. Therefore, when the piston 64 moves, the viscosity of the dilatant fluid increases, the movement resistance of the piston 64 increases, and the movement speed is reduced, so that the vibration (vibration) of the spent fuel rack 32 is attenuated.

  As described above, the spent fuel rack reinforcing structure according to the second embodiment has the plurality of cells 32a into which the spent fuel can be inserted from above along the vertical direction, and the lower part is the bottom of the spent fuel pool 31. Damper devices 51 and 61 are provided between the wall surface 31 b of the spent fuel pool 31 and the side surface 32 b of the spent fuel rack 32.

  Therefore, the spent fuel rack 32 can improve the earthquake resistance of the spent fuel rack 32 by suppressing the horizontal shaking by the damper devices 51 and 61.

  Moreover, in the reinforcement structure of the spent fuel rack of Example 2, a piston mechanism is provided as the damper devices 51 and 61, and the casing 52 or the container 65 filled with the dilatant fluid and the casing 52 or the container 62 are provided as the piston mechanism. The pistons 53 and 64 that are movable with respect to each other are provided. Therefore, in the spent fuel rack 32, when horizontal shaking occurs, the pistons 54 and 63 move, so that the viscosity of the dilatant fluid increases and the movement resistance of the pistons 54 and 63 increases, thereby suppressing the horizontal shaking. As a result, the earthquake resistance of the spent fuel rack 32 can be effectively improved.

  FIG. 10 is a plan view of a spent fuel pool representing a spent fuel rack reinforcing structure according to a third embodiment of the present invention, and FIG. 11 is a spent fuel pool representing a spent fuel rack reinforcing structure according to the third embodiment. FIG. 12 is a plan view of a spent fuel pool showing a modified example of the spent fuel rack reinforcement structure of the third embodiment. In addition, the same code | symbol is attached | subjected to the member which has the function similar to the Example mentioned above, and detailed description is abbreviate | omitted.

  As shown in FIGS. 10 and 11, the reinforcing structure of the spent fuel rack according to the third embodiment is provided with a damper device 71 between the wall surface 31 b of the spent fuel pool 31 and the side surface 32 b of the spent fuel rack 32. Configured. In this case, the damper device 71 is provided on all sides of the spent fuel rack 32.

  Each damper device 71 functions by movement of a dilatant fluid filled therein. That is, the damper device 71 is constituted by a container 72 that is filled with a dilatant fluid and is deformable. The container 72 has a hollow cylindrical shape, is filled with a dilatant fluid, and is deformable. And this container 72 is arrange | positioned between the wall surface 31b of the spent fuel pool 31, and the side surface 32b of the spent fuel rack 32, is suspended and supported by the suspension rope 74 via the attachment bracket 73, and is attached to a mounting bracket. 75 is fixed to the wall surface 31 b of the spent fuel pool 31.

  Therefore, the spent fuel rack 32 is fixed to the bottom 31 a of the spent fuel pool 31, and each side surface 32 b on the outer peripheral side is supported by the wall surface 31 b of the spent fuel pool 31 via the damper device 71. . At this time, when horizontal shaking occurs due to an earthquake or the like, the horizontal shaking of the spent fuel rack 32 is suppressed by each damper device 71.

  That is, when the upper part of the spent fuel rack 32 is shaken horizontally, the viscosity of the dilatant fluid hermetically filled in the container 72 is increased by the damper device 71, and the movement resistance of the spent fuel rack 32 increases and moves. By reducing the speed, the vibration (vibration) is attenuated.

  The container 72 in the damper device 71 is not limited to this configuration. For example, as shown in FIG. 12, the container 72 of the damper device 71a may be divided into a plurality of parts. Further, the shape of the container is not limited to a cylinder, and may be a rectangular tube shape, a cubic shape, a rectangular parallelepiped shape, a spherical shape, or the like.

  Thus, the spent fuel rack reinforcing structure of the third embodiment has a plurality of cells 32a into which spent fuel can be inserted from above along the vertical direction, and the lower part is the bottom of the spent fuel pool 31. Damper devices 71 and 71 a are provided between the wall surface 31 b of the spent fuel pool 31 and the side surface 32 b of the spent fuel rack 32. Therefore, the spent fuel rack 32 can improve the earthquake resistance of the spent fuel rack 32 by suppressing horizontal shaking by the damper devices 71 and 71a. Further, as the damper devices 71 and 71a, the dilatant fluid is filled in the container 72 and used, so that the shake of the spent fuel rack 32 can be easily suppressed with a simple configuration.

  FIG. 13 is a longitudinal sectional view of a spent fuel pool showing a reinforcement structure for a spent fuel rack according to Embodiment 4 of the present invention. In addition, the same code | symbol is attached | subjected to the member which has the function similar to the Example mentioned above, and detailed description is abbreviate | omitted.

  The spent fuel rack reinforcement structure of the fourth embodiment is configured by providing a damper device 81 between a wall surface 31b of the spent fuel pool 31 and a side surface 32b of the spent fuel rack 32 as shown in FIG. ing. In this case, the damper device 81 is provided on all sides of the spent fuel rack 32.

  Each damper device 81 is composed of a pair of magnets 82 and 83 in which the same pole portions are arranged to face each other at a predetermined interval. That is, the first permanent magnet 82 is fixed to the wall surface 31 b of the spent fuel pool 31 by the mounting rod 84. On the other hand, the second permanent magnet 83 is fixed to the side surface 32 b of the spent fuel rack 32 by a mounting rod 85. The first permanent magnet 82 and the second permanent magnet 83 are opposed to each other with a predetermined gap, and the facing surfaces are set to the same polarity, that is, N poles (or S poles). The repulsive force is acting.

  Therefore, the spent fuel rack 32 is fixed to the bottom 31 a of the spent fuel pool 31, and each outer peripheral side surface 32 b is supported by the wall surface 31 b of the spent fuel pool 31 via the damper device 81. . At this time, if horizontal shaking occurs due to an earthquake or the like, the horizontal shaking of the spent fuel rack 32 is suppressed by each damper device 81.

  In other words, when the upper part of the spent fuel rack 32 swings horizontally, the second permanent magnet 83 approaches or separates from the first permanent magnet 82 by the damper device 81. However, since the opposing surfaces of the first permanent magnet 82 and the second permanent magnet 83 are set to the same pole, they are prevented from approaching each other by repelling each other, and the movement resistance of the spent fuel rack 32 is increased. By doing so, the vibration (vibration) is attenuated.

  As described above, the spent fuel rack reinforcing structure according to the fourth embodiment includes the plurality of cells 32a into which the spent fuel can be inserted from above along the vertical direction, and the lower portion is the bottom of the spent fuel pool 31. A damper device 81 is provided between a wall surface 31b of the spent fuel pool 31 and a side surface 32b of the spent fuel rack 32 in the spent fuel rack 32 that is fixed to the same. A pair of magnets 82 and 83 are provided so as to face each other with an interval of.

  Therefore, the spent fuel rack 32 can improve the earthquake resistance of the spent fuel rack 32 by suppressing the horizontal shaking by the damper device 81. Further, by providing the pair of magnets 82 and 83 as the damper device 81, it is possible to easily suppress the vibration of the spent fuel rack 32 with a simple configuration.

  FIG. 14 is a longitudinal sectional view of a spent fuel pool showing a reinforcement structure for a spent fuel rack according to Embodiment 5 of the present invention. In addition, the same code | symbol is attached | subjected to the member which has the function similar to the Example mentioned above, and detailed description is abbreviate | omitted.

  As shown in FIG. 14, the reinforcing structure of the spent fuel rack according to the fifth embodiment is configured by providing a damper device 91 between a wall surface 31 b of the spent fuel pool 31 and a side surface 32 b of the spent fuel rack 32. ing. In this case, the damper device 91 is provided on all sides of the spent fuel rack 32.

  Each damper device 91 is configured by a bag-like member 92 whose internal pressure increases when the seismic intensity exceeds a predetermined seismic intensity. That is, the bag-like member 92 is formed so as to form a hollow sealed shape by a material that can be expanded and contracted, and one side is fixed to the wall surface 31b of the spent fuel pool 31 by the mounting rod 93, and the other side is fixed by the mounting rod 94. It is fixed to the side surface 32 b of the spent fuel rack 32. Further, the spent fuel pool 31 is provided with an air pump 95 on the upper surface portion 31 c and connected to the bag-like member 92 via a supply hose 96. The control device 97 can drive and control the air pump 95, drives the air pump 95 based on the detection result of the seismic intensity sensor 98, and can supply air to the bag-like member 92 via the supply hose 96. Yes.

  Therefore, the spent fuel rack 32 is fixed to the bottom 31 a of the spent fuel pool 31, and each outer side surface 32 b is supported by the side surface 32 b of the spent fuel rack 32 via the damper device 91. . At this time, when horizontal shaking occurs due to an earthquake or the like, the horizontal shaking of the spent fuel rack 32 is suppressed by each damper device 91.

  That is, when an earthquake occurs, the seismic intensity sensor 98 detects the seismic intensity of the occurred earthquake and outputs it to the control device 97. When the seismic intensity of the generated earthquake exceeds a predetermined seismic intensity set in advance, the control device 97 drives the air pump 95 and supplies air from the supply hose 96 to the bag-like member 92. Then, the bag-like member 92 is pressurized and expanded by supplying air therein, and presses against the bottom 31 a of the spent fuel pool 31 and the side surface 32 b of the spent fuel rack 32. Therefore, the shake (vibration) of the spent fuel rack 32 is attenuated by the expanded bag-like member 92.

  Thus, the spent fuel rack reinforcement structure of the fifth embodiment has a plurality of cells 32a into which spent fuel can be inserted from above along the vertical direction, and the lower part is the bottom of the spent fuel pool 31. A damper device 91 is provided between the wall surface 31b of the spent fuel pool 31 and the side surface 32b of the spent fuel rack 32, and the seismic intensity is preset as the damper device 91. In addition, a bag-like member 92 is provided in which the internal pressure increases when the predetermined seismic intensity is exceeded.

  Therefore, the spent fuel rack 32 can improve the earthquake resistance of the spent fuel rack 32 by suppressing the horizontal shaking by the damper device 91. Moreover, the shock resistance of the spent fuel rack 32 can be improved by providing the bag-like member 92 that can be expanded according to the seismic intensity as the damper device 91.

  In each of the above-described embodiments, the number, size, shape, and the like of the spent fuel rack 32 are described, but the number, size, and shape are not limited to those described.

  Further, in each of the above-described embodiments, the spent fuel rack reinforcement structure of the present invention has been applied to a pressurized water reactor, but it can also be applied to a boiling reactor (BWR: Boiling Water Reactor), It may be applied to any nuclear reactor.

11 reactor containment vessel 12 pressurized water reactor 13 steam generator 31 spent fuel pool 31a bottom 31b wall surface 32 spent fuel rack 32a cell 32b side surfaces 41, 51, 61, 71, 71a, 81, 91 damper device 42 cylinder 44 Piston 52 Casing (Cylinder)
53 Piston 65 Container (cylinder)
64 piston

Claims (1)

In a plurality of spent fuel racks having a plurality of cells into which spent fuel can be inserted from above along the vertical direction and whose lower part is fixed on the base frame at the bottom of the spent fuel pool,
A damper device is provided between a wall surface of the spent fuel pool and a side surface of the plurality of spent fuel racks;
The damper device is provided between a wall surface of the spent fuel pool and an upper side surface of the spent fuel rack, and is provided on four sides of the plurality of spent fuel racks,
Having a piston mechanism that functions by the movement of the cooling water immersed in the cooling water of the spent fuel pool and entering the interior;
The piston mechanism includes a cylinder and a piston, the outer diameter of the piston is set slightly smaller than the inner diameter of the cylinder, and the piston is movably supported with a predetermined gap functioning as an orifice in the cylinder. To be
A structure for reinforcing a spent fuel rack.

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