Nuclear power plant structure for resisting impact of large commercial aircraft

Abstract

The invention provides a nuclear power plant structure for resisting impact of a large commercial aircraft, which comprises a first-class plant and a second-class plant, and the first-class plant is provided with an inner containment and an outer containment; the second-class factory building is arranged adjacent to the first-class factory building, and an adjacent building surface is formed between the second-class factory building and the first-class factory building; wherein the inner containment is completely enclosed by the outer containment, the outer containment is partially enclosed by the adjacent building surfaces, and the thickness of the outer containment in the adjacent building surfaces is smaller than or equal to the thickness outside the adjacent building surfaces. According to the invention, the safety function of a nuclear power plant for resisting the impact of a large aircraft is decomposed, and a single-layer and double-layer mixed aircraft impact resistance structure with a double-layer containment, a single-layer plant wall and a roof is provided, so that the problem that aircraft impact resistance evaluation is not carried out in a targeted manner is solved; the use amount of reinforced concrete, the manufacturing cost and the occupied area of the nuclear power plant structure are increased, and site construction is difficult.

Description

Technical Field

[0001] The invention relates to the technical field of nuclear power plant protection, and in particular to a nuclear power plant structure capable of resisting impact from large commercial aircraft. Background Art

[0002] Nuclear power safety has received the most widespread and widespread attention, and safety has always been the eternal theme for achieving sustainable development of nuclear energy. For example, it is required that newly designed nuclear power plants should take into account the impact of malicious commercial aircraft collisions in their designs, and conduct a comprehensive assessment of the various effects of large commercial aircraft collisions to ensure the safety of nuclear power plants.

[0003] At present, redundant design plus physical isolation is commonly used to resist the impact of large commercial aircraft. Some power plants use independent structures that can resist the impact of large commercial aircraft. The corresponding structures need to carry out local effect, overall effect, vibration effect and fire effect assessment. In addition, some power plants make full use of the shielding effect and arrange the plant that needs to be protected in the middle to minimize the impact surface and reduce the area that needs structural assessment. In general, the specification requires that the relevant impact effects need to be analyzed and considered from the overall level, but does not subdivide the functional requirements of the relevant structures and give specific analysis categories.

[0004] At the same time, in the existing technology, the functions of specific items to be considered for anti-collision and the effects to be analyzed are not fully combined, and the assessment of anti-collision of large commercial aircraft is not well carried out in a targeted manner. Setting up a special structure to resist the impact of large commercial aircraft greatly increases the amount of reinforced concrete, increases the cost and land occupation, and brings difficulties to on-site construction.

[0005] It should be noted that the information disclosed in the above background technology section is only used to enhance the understanding of the background of the present invention and does not constitute any limitation to the present invention. Summary of the invention

[0006] In view of the shortcomings of the prior art mentioned above, the present invention provides a nuclear power plant structure that can withstand the impact of large commercial aircraft. The safety function of the nuclear power plant to withstand the impact of large aircraft is decomposed, and a single- and double-layer mixed anti-aircraft impact structure of a double-layer containment shell plus a single-layer plant wall and roof is proposed to solve the problem that the lack of targeted anti-aircraft impact assessment has increased the amount of reinforced concrete used, the cost and the land occupied by the nuclear power plant structure, causing difficulties in on-site construction.

[0007] The present invention provides a nuclear power plant structure capable of resisting impact of large commercial aircraft, comprising a first-class plant building and a second-class plant building, wherein the first-class plant building is provided with an inner containment shell and an outer containment shell; the second-class plant building is arranged adjacent to the first-class plant building, and an adjacent building surface is formed between the second-class plant building and the first-class plant building; wherein the outer containment shell completely encloses the inner containment shell, the adjacent building surface partially encloses the outer containment shell, and the thickness of the outer containment shell within the adjacent building surface is less than or equal to the thickness outside the adjacent building surface.

[0008] In one embodiment of the present invention, among adjacent building surfaces, when the height of a type-one factory building is greater than that of a type-two factory building, the area of ​​the adjacent building surface is increased by increasing the height of the type-two factory building.

[0009] In one embodiment of the present invention, adjacent building surfaces include walls and roofs, and the thickness of the walls and roofs of Class I and Class II factory buildings outside the adjacent building surfaces is greater than the thickness of the walls and roofs inside the adjacent building surfaces.

[0010] In one embodiment of the present invention, the thickness of the walls and roofs in a type of factory building is reduced according to the angle of impact resistance.

[0011] In one embodiment of the present invention, the vibration sensitive equipment in the first and second type factory buildings is arranged away from the walls and roofs that resist impact, and partitions are set on the vibration transmission path between the vibration sensitive equipment and the walls and roofs.

[0012] In one embodiment of the present invention, the walls of adjacent building surfaces are also formed between two adjacently arranged first-class factory buildings and between two second-class factory buildings.

[0013] In one embodiment of the present invention, between a Class I factory building and a Class II factory building, between two Class I factory buildings, and between two Class II factory buildings within adjacent building surfaces, a wall of one of the Class I factory buildings or the Class II factory buildings is shared.

[0014] In one embodiment of the present invention, the first type of factory building and the second type of factory building are arranged on the same common raft foundation.

[0015] In one embodiment of the present invention, within adjacent building surfaces, an outer containment shell of a type of plant and a wall of an adjacent building surface are connected to each other below a reference plane and are disconnected from each other above the reference plane.

[0016] In one embodiment of the present invention, within adjacent building surfaces, an outer containment shell of a type of plant and a wall of an adjacent building surface are partially connected to each other above a reference plane and are disconnected from each other at another part.

[0017] In one embodiment of the present invention, within adjacent building surfaces, the outer containment shell of a type of factory building is completely connected to the wall of the adjacent building surface.

[0018] In one embodiment of the present invention, an outer containment shell of a type of plant is separated from walls of adjacent building surfaces above a common raft foundation.

[0019] In one embodiment of the present invention, a protective structure is arranged between adjacent building surfaces that are disengaged from each other, and the protective structure covers the disengaged area to prevent debris from entering between the adjacent building surfaces.

[0020] In one embodiment of the present invention, it also includes a deployed fire partition barrier, and the fire partition barrier meets the fire resistance limit requirements of a Class I factory building or a Class II factory building.

[0021] In one embodiment of the present invention, inner lining or outer hanging protection is provided on the outer containment shell and the wall of the Class I and Class II factory buildings.

[0022] In one embodiment of the present invention, a method for evaluating the structure of a nuclear power plant for resisting impacts of large commercial aircraft is also provided, including: determining specific functional requirements for the nuclear power plant to resist impacts based on the overall protection goal of the nuclear power plant to resist impacts; determining evaluation items of the nuclear power plant according to the specific functional requirements, and performing item analysis; and determining the type of evaluation effect based on the results of the item analysis.

[0023] Among them, the overall protection objectives include the structural integrity and functional integrity of the containment and spent fuel pool in the nuclear power plant. The specific functional requirements of structural integrity include the overall stability of the nuclear power plant, no plastic collapse, no penetration and armor fragmentation, and the barrier remains intact and meets the fire resistance limit requirements; the specific functional requirements of functional integrity include the residual heat removal system equipment function and the leakage prevention function of the inner containment and spent fuel pool. The evaluation items of the nuclear power plant include the inner containment, spent fuel pool, overall plant structure, outer containment, plant exterior walls and roofs, partition barriers, and equipment required for safe shutdown and residual heat removal. The evaluation effects corresponding to the evaluation items include at least one of the overall effect, local effect, fire effect, and vibration effect.

[0024] The beneficial effects of the present invention are as follows: by taking over and decomposing the safety function of a nuclear power plant to resist the impact of large aircraft, the overall safety goal is implemented on the specific items of the nuclear power plant, and at the same time, the specific functions of the nuclear power plant are matched one by one with the items and the evaluation effects, and targeted analysis and measures are taken, and a single- and double-layer mixed anti-aircraft impact structure of a double-layer containment shell plus a single-layer plant wall and roof is proposed. While effectively ensuring the safety of the nuclear power plant, the amount of reinforced concrete is reduced, the floor space is reduced, and the difficulty of on-site construction is reduced.

[0025] It is to be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The drawings herein are incorporated into the specification and constitute a part of the specification, showing embodiments consistent with the present invention, and together with the specification, are used to explain the principles of the present invention. Obviously, the drawings described below are only some embodiments of the present invention, and for those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative work. In the drawings:

[0027] Figure 1 A schematic cross-sectional view of a nuclear power plant structure for resisting impact of a large commercial aircraft according to the present invention;

[0028] Figure 2 This is a schematic diagram of the angle of the nuclear power plant structure in the present invention to resist the impact of a large commercial aircraft;

[0029] Figure 3 A flow chart of a method for evaluating a nuclear power plant for withstanding a large commercial aircraft impact according to the present invention;

[0030] Figure 4 A logical decomposition diagram of the method of evaluating a nuclear power plant for withstanding a large commercial aircraft impact according to the present invention. DETAILED DESCRIPTION

[0031] The following describes the embodiments of the present invention by specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied by other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the features in the following embodiments and embodiments can be combined with each other without conflict. It should also be understood that the terms used in the embodiments of the present invention are to describe specific specific embodiments, rather than to limit the scope of protection of the present invention.

[0032] See also Figures 1 to 4 . It should be noted that the structures, proportions, sizes, etc. illustrated in the drawings in this specification are only used to match the contents disclosed in the specification for people familiar with this technology to understand and read, and are not used to limit the limiting conditions for the implementation of the present invention, so they have no substantial technical significance. Any structural modification, change in proportional relationship, or adjustment of size, without affecting the effects and purposes that can be achieved by the present invention, should still fall within the scope of the technical content disclosed by the present invention. At the same time, the terms such as position and quantitative relationship cited in this specification are only for the convenience of description, and are not used to limit the scope of the implementation of the present invention. Changes or adjustments in their relative relationships should also be regarded as the scope of the implementation of the present invention without substantially changing the technical content.

[0033] See also Figure 1The present invention provides a nuclear power plant structure capable of resisting impact from large commercial aircraft, comprising a first-class plant building 100 and a second-class plant building 200, wherein the first-class plant building 100 is provided with an inner containment shell and an outer containment shell 101; the second-class plant building 200 is arranged adjacent to the first-class plant building 100, and an adjacent building surface is formed between the second-class plant building 200 and the first-class plant building 100; wherein the outer containment shell 101 completely encloses the inner containment shell, the adjacent building surface partially encloses the outer containment shell 101, and the thickness of the outer containment shell 101 within the adjacent building surface is less than or equal to the thickness outside the adjacent building surface.

[0034] Specifically, in the embodiment of the present invention, according to the purpose of different building facilities in the nuclear power plant structure, they can be divided into a first-class plant 100 and a second-class plant 200. The first-class plant 100 is a facility directly involved in the operation and transportation of nuclear fuel, such as a reactor building (such as an attached Figure 1 The plant building 1) and the shutdown equipment building and the spent fuel pool building (such as the attached Figure 1 The second-class plant 200 is used as a facility to support the functions of the first-class plant 100 and meet the operation of the nuclear power plant, such as steam generators, generators, control rooms and transmission system buildings. In the structure of a nuclear power plant, the second-class plant 200 is generally arranged with the reactor of the first-class plant 100 as the center, and its safety protection function is ensured while meeting the power generation needs. Since there is nuclear fuel in the first-class plant 100, the first-class plant 100 generally adopts a structure of an inner containment shell with an outer containment shell 101 in the reactor building. The inner containment shell is used to protect the nuclear reactor and its related equipment. It is usually built with high-strength materials and can withstand risks such as external impact and radiation leakage. The outer containment shell 101 is located outside the inner containment shell, providing an additional layer of protection to further reduce the impact on the environment and the public when an accident occurs. In a type of plant 100 such as a reactor shutdown equipment building and a spent fuel pool building, a conventional building wall 102 structure can generally be used, and corresponding safety measures are taken for the wall 102 structure to meet the risks of resisting external impact, radiation leakage, etc.

[0035] More specifically, in the structure of a nuclear power plant, a Class II plant 200 is usually adjacent to a Class I plant 100 and may include auxiliary facilities such as a control room, a maintenance workshop, etc. In this way, an adjacent building surface is formed between the Class II plant 200 and the Class I plant 100. On the one hand, it is necessary to consider the isolation and safety at the adjacent building surface; on the other hand, for the building facilities located on the adjacent building surface in the structure of the nuclear power plant, its functional requirements are targeted to optimize the structure of the Class I plant 100 or the Class II plant 200 in the adjacent building surface. In other words, under the premise of meeting the structural safety requirements of the nuclear power plant, such as anti-collision requirements, by thinning the walls 102 or containment of the Class I plant 100 or the Class II plant 200 in the adjacent building surface and meeting its radiation protection standards, the optimized design is used to reduce the construction and maintenance costs without affecting the functionality and safety of the plant.

[0036] In this way, the first-class factory building 100 and the second-class factory building 200 are fully utilized as surrounding buildings to play a shielding and protective role. The outer containment shell is set to protect the inner containment shell from the impact of large aircraft, and does not affect the arrangement and design of the systems, equipment and ring cranes in the inner containment shell. Figure 3 As shown, if the plant 3 needs to be protected, it can be protected by the plants 4 and 6, and the connected wall 102 can be thinned; if the plant 2 needs to be protected, it can be protected by the plants 5 and 7 and other structures in the outer area, so that the wall 102 (that is, the adjacent building surface) connecting the plant 2 and the plants 5 and 7 can be thinned. For example, the thickness of the outer containment of the plant 1 can be thinned by 200mm to 500mm at the height below the roof of the plants 2, 3, 5, and 7. By using the building structure of the outer plant to resist impact damage, the thickness of the components can be reduced by designing the wall 102 with a variable cross-section, thereby reducing the engineering cost. The surrounding plants below the containment are used for shielding to reduce the impact effect of the aircraft.

[0037] It should be noted that in the embodiment of the present invention, high-strength and high-toughness concrete can also be used to further reduce the thickness of the structure. However, the new material needs to be fully demonstrated. Similarly, a steel plate concrete structure can be used instead of a reinforced concrete structure. It is also possible to further optimize the protective structure and adopt a single-layer containment shell, but it is necessary to further analyze the impact of a large aircraft impact on the prestressed containment shell and the adverse effects on the ring crane.

[0038] That is to say, in the double-layer containment adopted in the embodiment, the outer containment 101 (ordinary concrete structure) resists external events such as large aircraft collisions, and the inner containment (prestressed containment) only needs to consider the impact of internal loads, and the ring hanger of the inner containment will not be affected. After changing to a single-layer containment (prestressed containment), it is necessary to consider both the impact of large aircraft collisions and the impact of internal accidents. Therefore, it is necessary to further analyze the impact of large aircraft directly hitting the ring hanger, and also consider the impact of aircraft collisions on the prestressed containment. The specific analysis process is that the aircraft directly acts on the prestressed containment, analyzes the failure mode, the loss of prestress, the impact on the bearing capacity of the structure, etc. When hitting the ring hanger, it is necessary to consider whether the deformation and vibration caused by the impact will cause the ring hanger to fall. In this way, a single-layer containment can be adopted on the premise of meeting the impact performance requirements.

[0039] See also Figure 1 and Figure 2 In one embodiment, among adjacent building surfaces, when the height of the first-class factory building 100 is greater than the height of the second-class factory building 200, the height of the second-class factory building 200 is increased to increase the area of ​​the adjacent building surface.

[0040] Specifically, in the embodiment of the present invention, the layout of the related facilities of the plant 4 and the plant 6 is designed to be a relatively high structure, and its height is used to form a protective barrier, thereby reducing the risk of large aircraft accidentally hitting the building facilities in the plant 3. It is also possible to consider setting up protective walls or other structures in the facilities of the plant 4 and the plant 6 to increase the height and increase its impact resistance. At the same time, by raising the height of the related facilities and dispersing them, the impact of the impact force can be effectively dispersed, reducing the overall area that needs to be protected in the safety plant and the fuel plant. As shown in the attached Figure 1 As shown, for example, relevant facilities are arranged around the safety plant and the fuel plant, that is, the height of the relevant facilities in the plant 4 and the plant 6 is raised as much as possible, so that a certain degree of shielding and protection is provided for the building facilities in the plant 3, so as to effectively resist the impact of large aircraft and reduce the area that needs to be protected in the safety plant and the fuel plant.

[0041] Furthermore, the adjacent building surfaces include walls 102 and roofs, and the thickness of the walls 102 and roofs outside the adjacent building surfaces of the first-class factory building 100 and the second-class factory building 200 is greater than the thickness of the walls 102 and roofs inside the adjacent building surfaces. The thickness of the walls 102 and roofs in the first-class factory building 100 is reduced according to the angle of the impact resistance.

[0042] Furthermore, the wall 102 and roof thickness outside the adjacent building surface are designed to be larger to enhance their ability to resist external impact; while the wall 102 and roof thickness inside the adjacent building surface can be appropriately reduced to save materials and reduce the structural burden. The overall safety and protection capabilities can be improved by selecting high-strength, impact-resistant materials, especially on the exterior walls and roofs. Structural reinforcement is carried out in weak areas, and reinforced concrete or other reinforcing materials are used to improve impact resistance. In other words, by strengthening the walls 102 and roofs of the safety plant and fuel plant that are directly impacted, instead of setting up a special structure to resist large aircraft impacts. In this way, flexibility is left in the design of the nuclear power plant, so that different walls 102 and roofs can be adjusted according to actual needs, while meeting safety standards and enhancing the civil engineering advantages of building facilities.

[0043] Thus, a detailed analysis is performed based on the potential impact angle to determine in which directions the thickness of the wall 102 and the roof needs to be increased to ensure that these areas can effectively resist possible impacts (such as the adjacent Figure 2 For example, the roof of the safety building and the fuel building is considered to be hit by a large aircraft at an angle of 10 degrees (the angle between the axis of the aircraft and the roof), so the thickness of the roof is reduced; it also includes the wall 102 of the fuel building 2 close to the reactor building 1. When the aircraft hits, it can only hit at a certain angle in the horizontal direction and the direction of gravity, which will reduce the impact force, so the thickness of the wall 102 can be thinner; the shielding effect of the steam turbine platform of the conventional island building is also taken into account. When the aircraft hits the outer wall of the safety building, it is necessary to consider the possible impact angle and impact area at the same time.

[0044] Furthermore, the vibration sensitive devices in the Class I factory building 100 and the Class II factory building 200 are arranged away from the walls 102 and the roof for resisting impact, and partitions are provided on the vibration transmission path between the vibration sensitive devices and the walls 102 and the roof.

[0045] Specifically, in order to ensure the safety and stability of vibration-sensitive equipment in nuclear power plants, vibration-sensitive equipment is arranged in areas away from the impact-resistant walls 102 and roofs to reduce the risk of being directly affected by external vibrations. At the same time, partitions are set between the vibration-sensitive equipment and the walls 102 and roofs, such as using elastic materials or sound insulation panels, to effectively isolate the vibration transmission path and reduce the impact of vibration on the equipment. It is also possible to consider installing vibration isolation devices, such as elastic supports and shock absorbers, to further reduce the vibration transmitted to the equipment from the ground and structure. In this way, considering the vibration effect of a large aircraft impact, on the one hand, the sensitive equipment is arranged away from the impact area, and on the other hand, the impact of vibration is reduced by setting partitions on the transmission path.

[0046] See also Figure 1 and Figure 2In one embodiment, the walls 102 of adjacent building surfaces are also formed between two adjacently arranged Class I factory buildings 100 and between two Class II factory buildings 200; between a Class I factory building 100 and a Class II factory building 200, between two Class I factory buildings 100, and between two Class II factory buildings 200 within adjacent building surfaces, the walls 102 of one of the Class I factory buildings 100 or the Class II factory buildings 200 are shared.

[0047] Specifically, in the embodiment of the present invention, between different adjacently distributed plants, the thickness of the wall 102 in the adjacent building surface can be reduced while meeting the requirements of anti-aircraft impact performance, thereby optimizing the civil construction of building facilities. Similarly, in adjacent building surfaces, that is, between a Class I plant 100 and a Class II plant 200, between two Class I plants 100 (such as a reactor building, a shutdown equipment building, and a spent fuel pool building), or between two Class II plants 200, a shared wall 102 can be designed to save building materials and occupied space, i.e., site utilization, while improving the overall stability of the adjacent building facility structure.

[0048] See also Figure 1 and Figure 2 In one embodiment, the first type of plant 100 and the second type of plant 200 are arranged on the same common raft foundation. In adjacent building surfaces, the outer containment shell 101 of the first type of plant 100 and the wall 102 in the adjacent building surface are connected to each other below the reference plane and are disconnected from each other above the reference plane. In adjacent building surfaces, the outer containment shell 101 of the first type of plant 100 and the wall 102 in the adjacent building surface are connected to each other in part above the reference plane and are disconnected from each other in another part.

[0049] Specifically, in an embodiment of the present invention, by arranging different factory buildings on the same raft foundation, the shared raft foundation can reduce the construction cost of the infrastructure and reduce the overall construction cost. The centralized setting can effectively utilize the site, improve the efficiency of land use, and facilitate the later management and maintenance. The same raft foundation can provide better overall stability and reduce structural problems caused by different foundation settlements. During on-site construction, the complexity and construction period of foundation construction can be reduced, and the construction efficiency can be improved. The unified foundation design can enhance the seismic performance and ensure the safety of each factory building under extreme conditions such as earthquakes.

[0050] More specifically, the connection method between the outer containment 101 and the wall 102 between different buildings in adjacent structures is very important, especially between a Class I building 100 (such as a reactor building) and an adjacent building surface such as a Class II building 200 (such as an auxiliary facility). Class I buildings 100 usually carry higher safety standards, and the outer containment 101 is designed to prevent leakage of radioactive materials. The connection parts of the Class II buildings 200 of the adjacent building surfaces need to ensure the integrity of the containment to prevent mutual influence in the event of an accident. For example, the attached Figure 3As shown, the outer containment shell 101 of a type of plant 100 such as plant 1 and the type of plant 100 within the adjacent building surface such as plants 2 and 3 and the type of plant 200 such as plants 5 and 7 are connected at the building reference plane by selecting a fixed ground elevation or other stable reference object according to actual conditions, and taking this as the reference plane at 0m and below; the plants 2 and 3 above 0m are disconnected from the outer containment shell 101 of the plant 1; the plants 5 and 7 above 0m are still connected to the outer containment shell 101 of the plant 1.

[0051] Being connected above and below the datum plane can provide better earthquake and impact resistance and ensure the overall stability of the two under extreme conditions. The design of disconnecting a part of the datum plane from each other helps to clarify the functional area and facilitate management and operation. For example, some equipment or systems may only work in a type of plant 100, and the separate design can reduce interference. The disconnected design can reduce the impact on adjacent buildings during maintenance or overhaul, and improve operational flexibility. At the same time, different plant buildings may have different degrees of expansion or contraction due to temperature changes or settlement, and separate settings can avoid structural problems caused by mutual constraints.

[0052] In this way, adjacent buildings adopt different connection and separation designs on both sides of the base plane to balance safety, structural stability and functional flexibility, ensuring that the nuclear power plant can maintain good safety performance under normal operation and extreme conditions.

[0053] See also Figure 1 In the adjacent building surface, the outer containment 101 of the first type of plant 100 is completely connected with the wall 102 in the adjacent building surface. The outer containment 101 of the first type of plant 100 and the wall 102 in the adjacent building surface are separated from each other above the common raft foundation.

[0054] Specifically, the outer containment shell 101 of the first-class plant 100 and the wall 102 of the adjacent building surface, such as the second-class plant 200, are completely connected by design, which can provide better overall stability and help resist extreme events such as earthquakes. In the event of an accident, the connection part can effectively prevent the leakage of radioactive materials and enhance safety. It also reduces interface problems during construction and may reduce construction complexity. The outer containment shell 101 of the first-class plant 100 and the wall 102 of the adjacent building surface, such as the second-class plant 200, are designed to be detached from the common raft foundation, which can limit the scope of impact in the event of an accident and improve safety. Each plant can be independently designed and operated according to different functions and needs to enhance flexibility. When carrying out maintenance or expansion, the impact on other plants can be reduced. As shown in the attached Figure 1As shown in the figure, the walls 102 between different factory buildings and between the outer containment vessel 101 are designed with different thicknesses or are connected or disconnected with each other according to needs. The connection and disconnection between all adjacent building surfaces are only shown in the figure and do not represent them, which will not be elaborated here.

[0055] Therefore, when choosing the connection method between the first-class plant 100 and the adjacent building surface, it is necessary to comprehensively consider safety, structural stability, maintenance convenience and economy. Full connection provides better integrity, while the design detached from the common raft foundation provides a higher safety isolation effect. Design decisions should be based on the specific needs and risk assessment of the project.

[0056] More specifically, a protective structure is arranged between the mutually disengaged adjacent building surfaces, and the protective structure covers the mutually disengaged area to prevent debris from entering between the adjacent building surfaces. That is, the gaps generated in the area where the roof and the outer layer are safely disengaged need to be specially designed to prevent fuel leakage. For example, an inverted L-shaped hood structure is used to build a barrier to prevent fuel from entering. In addition, a parapet and a filling layer composed of fireproof materials can be set to form a multi-layered defense structure, which is more conducive to protection against aircraft impact (for details, please refer to the technical solution of ZL201920600571.7).

[0057] It should be noted that according to the overall layout of different plant buildings in the nuclear power plant, different schemes are selected to determine the connection or disconnection relationship between different plant rooms in adjacent building surfaces, so as to reduce the floor response spectrum as much as possible. If all are connected, the overall stiffness of the structure can be increased, and the floor response spectrum will be reduced overall. If all the plant buildings are connected, the staggered floors in different areas will cause inconvenience in construction. The plant buildings also need to be calculated together, and the modeling and calculation efficiency is low. In this way, in order to reduce the floor response spectrum and improve the modeling and calculation efficiency, the connection can be maintained in key areas, while disconnection can be achieved in other areas. This method can take into account both stiffness and flexibility. In the design stage, the relative positions of the plant buildings are optimized to reduce staggering, stress concentration and calculation complexity. Modern software and algorithms are used to improve calculation efficiency, and multi-scenario simulations are performed at the same time to analyze the performance of different schemes. Combined with specific design requirements, construction conditions and subsequent maintenance considerations, ensure that the nuclear power plant structure strikes a balance between safety and economy.

[0058] Furthermore, it also includes the deployment of fire partition barriers, which meet the fire resistance limit requirements of Class I plant 100 or Class II plant 200. According to the fire protection standards for building facilities of nuclear power plants, building materials with excellent fire resistance are selected to ensure that the fire partition barriers can withstand the fire temperature for a specified time without structural failure. Determine the appropriate wall 102 thickness to meet the fire resistance limit requirements. Generally, the thickness of the fire-resistant wall is related to the type of material used and the fire protection level. Suitable fireproof materials are used to seal the joints and wall-penetrating pipes of the fire partition barriers to prevent the spread of flames and smoke. Standard fire doors are set between fire partitions to ensure that the spread of fire can be effectively blocked in the event of a fire. By considering the impact of the fire, corresponding fire resistance limit requirements are proposed for the fire partition barriers to ensure that the partitions will not affect each other.

[0059] Furthermore, the outer containment 101 and the wall 102 of the first-class factory building 100 and the second-class factory building 200 are provided with inner lining or external hanging protection. In the embodiment of the present invention, the outer containment can be provided with a steel lining or a hanging net to avoid the back armor fragmentation caused by the impact of hard projectiles, which can effectively avoid the secondary damage to the items in the room. The outer wall and the outer containment can adopt external hanging protection facilities (energy absorbing structure) or apply energy absorbing materials to reduce the destructive effect of the structure caused by the impact of the aircraft.

[0060] See also Figure 2 and Figure 3 The present invention provides a method for evaluating a nuclear power plant against a large commercial aircraft impact, comprising:

[0061] Based on the overall protection objectives of nuclear power plants against impact, determine the specific functional requirements for nuclear power plants against impact;

[0062] Determine the assessment items of the nuclear power plant according to specific functional requirements and conduct item analysis;

[0063] Determine the type of effect to be assessed based on the results of the item analysis.

[0064] Specifically, in an embodiment of the present invention, when evaluating the ability of a nuclear power plant to withstand impacts from large commercial aircraft, its overall protection objectives may include: protecting key facilities such as ensuring that nuclear reactors and important safety systems are not damaged in impact events. Maintaining structural integrity such as preventing structural collapse or major damage caused by impact. Preventing leakage of radioactive materials such as ensuring that nuclear materials and radioactive materials do not leak after an impact. The specific functional requirements for resisting impacts may include: impact-resistant design, such as the structure must have sufficient strength and toughness to withstand the impact of an aircraft impact. The performance of the protective wall 102, such as the wall 102 should be designed to have high compressive and impact resistance and be able to absorb energy. The stability of the support system, such as ensuring that the foundation and support structure will not become unstable under impact.

[0065] More specifically, the assessment items for the corresponding nuclear power plant may include: structural materials such as concrete, steel, etc., to evaluate their impact resistance. Wall 102 design such as material thickness, shape and connection method. Support system such as the design and stability of structural foundations, columns, beams, etc. Containment such as the integrity and impact resistance of the external protective shell. The corresponding item analysis may include: material performance analysis such as evaluating the strain and yield strength of different materials under high-speed impact. Structural simulation analysis such as simulating impact events using the finite element method to analyze the response of the structure under different impact forces. Support system stability analysis such as checking the performance of the foundation and support system under extreme conditions. Containment performance evaluation such as analyzing whether the design of the containment meets the impact resistance standards.

[0066] Furthermore, based on the evaluation effect type determined by the item analysis results, the risk type caused to each function of the nuclear power plant is determined. For example, for impact analysis, the physical damage that may be caused by an aircraft impact is simulated to evaluate its impact on the safety function. Analyze the risks in different scenarios to determine the necessary design improvements and protective measures. By clarifying the overall protection goals and specific functional requirements of the nuclear power plant structure against impact and conducting a detailed item analysis, the performance of the nuclear power plant in the face of various external shocks can be effectively evaluated, so as to develop a more reasonable and effective protection design plan.

[0067] Thus, according to the above functional decomposition, after in-depth and systematic research on various effects of aircraft impact, the embodiment of the present invention proposes a new type of nuclear power plant structure resistant to large aircraft impact (single-double-layer mixed anti-aircraft impact structure, double-layer containment shell plus single-layer plant wall 102 and roof). On the one hand, the safety of the nuclear power plant is effectively guaranteed, and the outer containment shell 101 can well resist the effects of external disasters and ensure the safety of the inner containment shell; on the other hand, shielding is arranged around the fuel plant (including the spent fuel pool) and the safety plant (including the main control room) as much as possible to avoid direct impact of large aircraft, and the outer wall 102 and roof that are directly impacted are thickened.

[0068] See also Figure 2 and Figure 3 In one embodiment, the overall protection objectives include the structural integrity and functional integrity of the containment and spent fuel pool in the nuclear power plant. The specific functional requirements of the structural integrity include the overall stability of the nuclear power plant, no plastic collapse, no penetration and armor fragmentation, and the barrier remains intact and meets the fire resistance limit requirements; the specific functional requirements of the functional integrity include the equipment function of the residual heat removal system and the leakage prevention function of the inner containment and the spent fuel pool.

[0069] Specifically, in the embodiments of the present invention, the specific functional requirements of structural integrity include overall stability, that is, the design of the nuclear power plant must ensure that after the impact, the overall structure remains stable without tilting or displacement. No plastic collapse occurs, that is, its structural materials should have sufficient strength and toughness to prevent permanent deformation or collapse under high-energy impact. No penetration and fragmentation occur, that is, the outer layer of the containment and the spent fuel pool must be designed to effectively resist the impact and prevent the aircraft or its wreckage from penetrating the structure. The barrier remains intact, that is, the key barrier (such as the containment) must ensure that there are no cracks or damage after the impact, maintain its integrity, and prevent the leakage of radioactive materials. The fire resistance limit requirement is that the structural materials and design must meet the fire resistance standards to prevent the fire caused by the impact from causing further damage to the structure.

[0070] More specifically, the specific functional requirements of functional integrity include the residual heat removal system equipment function, that is, the nuclear power plant must have an effective residual heat removal system to ensure that in the event of an accident, the heat in the reactor can be discharged in time to prevent overheating. The anti-leakage function of the inner containment, that is, the inner containment must be designed to effectively prevent the leakage of radioactive materials and coolants to ensure the safety of the environment and personnel. The anti-leakage function of the spent fuel pool, that is, to ensure the sealing of the spent fuel pool to avoid leakage after the impact and affect the surrounding environment and safety. In this way, by clarifying the specific requirements of structural integrity and functional integrity, the safety of nuclear power plants when hit by large commercial aircraft is ensured.

[0071] For further information, see Figure 3 The assessment items of the nuclear power plant include the inner containment, spent fuel pool, overall plant structure, outer containment 101, plant exterior walls and roof, partition barriers, and equipment required for safe shutdown and residual heat removal.

[0072] The main contents of the evaluation items of nuclear power plants include: the inner containment used to protect the reactor core and resist external impact and leakage of radioactive materials, and its evaluation contents include structural strength, material durability, earthquake resistance, etc. The spent fuel pool used to safely store spent fuel and prevent the spread of radioactive materials, and its evaluation contents include sealing, cooling system efficiency, and pool structural integrity. The overall plant structure used to support the facilities and equipment of the entire nuclear power plant, and its evaluation contents include structural stability, earthquake-resistant design, construction quality, etc. The outer containment 101 used as a second line of protection to prevent the leakage of radioactive materials, and its evaluation contents include impact resistance, sealing and durability. The outer walls and roofs of the plant used to protect internal equipment and personnel, and its evaluation contents include wind pressure resistance, earthquake resistance, waterproofing and thermal insulation performance. The partition barriers used to limit the impact of accidents and protect key equipment, and its evaluation contents include safety isolation, fire and explosion protection design. The equipment required to ensure safe shutdown and effective discharge of residual heat in an emergency, and its evaluation contents include system redundancy, reliability and effectiveness of emergency response plans. Through a comprehensive assessment of the above items, the safety and reliability of the nuclear power plant in normal operation and emergency situations are ensured.

[0073] For further information, see Figure 3 The evaluation effects corresponding to the evaluation items include at least one of overall effect, local effect, fire effect and vibration effect.

[0074] In an embodiment of the present invention, in the impact resistance assessment of the structure of a nuclear power plant, the assessment effects corresponding to the assessment items may specifically include overall effects, local effects, fire effects, and vibration effects. Overall effects refer to the impact on the stability and function of the entire structure. If the external impact causes the overall collapse of the nuclear reactor building, it will directly affect the operation of the safety system and may lead to catastrophic consequences. Local effects refer to the damage caused by the impact to a certain part of the structure or key equipment. For example, the impact causes a pipe in the cooling system to rupture, thereby affecting the supply of cooling water, but the overall structure remains stable. Fire effects focus on the fire risk caused by the impact and its impact on the structure and equipment. Since the impact causes flammable materials to catch fire, it may cause equipment damage or a larger range of fire spread. Vibration effects refer to the structural vibration caused by the impact and its impact on key systems. Strong vibrations may cause the equipment to loosen or fail, affecting the normal operation of the safety system. In this way, different types of assessment effects are caused according to different assessment items, and comprehensive consideration of these effects helps to accurately assess the safety and reliability of nuclear power plants when they are hit.

[0075] That is to say, in the embodiment of the present invention, according to the overall protection goal of the nuclear power plant against the impact of large commercial aircraft, that is, the reactor core is kept cool or the containment is kept intact, and the spent fuel is kept cool or the spent fuel pool is kept intact. In this way, the function is transferred in combination with the protection concept and requirements, and the logical relationship of the safety function decomposition against the impact of large aircraft is established, the main safety functions of resisting aircraft impact are determined, and the functions that each item of the nuclear power plant needs to undertake and the corresponding effect evaluation are clarified. At the same time, it can provide guidance for the overall layout of the plant, and better centralize the protection of the items that need to be protected in the nuclear power plant.

[0076] In summary, the present invention provides a method for evaluating a nuclear power plant for resisting impacts of large commercial aircraft. By studying the various effects of an aircraft impact through functional decomposition, the overall safety goal is effectively transferred to specific items, and targeted analysis and measures are taken. Thus, a nuclear power plant structure for resisting aircraft impacts with a single- and double-layer hybrid structure, a double-layer containment shell plus a single-layer plant wall and roof is proposed, and shielding is arranged around the fuel plant and the safety plant as much as possible to avoid direct impacts from aircraft. While effectively ensuring the safety of the nuclear power plant, the amount of reinforced concrete is reduced, the floor space is reduced, and the difficulty of on-site construction is reduced.

[0077] The above embodiments are merely illustrative of the principles and effects of the present invention, and are not intended to limit the present invention. Anyone familiar with the art may modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by a person of ordinary skill in the art without departing from the spirit and technical concept disclosed by the present invention shall still be covered by the claims of the present invention.

Claims

1. A nuclear power plant structure capable of withstanding impact with a large commercial aircraft, characterized in that: include: A first-class factory building (100), wherein the first-class factory building (100) is provided with an inner containment shell and an outer containment shell (101); as well as A second-class factory building (200), wherein the second-class factory building (200) is arranged adjacent to the first-class factory building (100), and an adjacent building surface is formed between the second-class factory building (200) and the first-class factory building (100); The outer containment shell (101) completely encloses the inner containment shell, the adjacent building surface partially encloses the outer containment shell (101), and the thickness of the outer containment shell (101) within the adjacent building surface is less than or equal to the thickness outside the adjacent building surface.

2. The nuclear power plant structure according to claim 1, characterized in that: In the adjacent building surfaces, when the height of the first-class factory building (100) is greater than the height of the second-class factory building (200), the area of ​​the adjacent building surfaces is increased by increasing the height of the second-class factory building (200).

3. The nuclear power plant structure according to claim 2, characterized in that: The adjacent building surfaces include walls (102) and roofs, and the thickness of the walls (102) and roofs of the first-class factory building (100) and the second-class factory building (200) outside the adjacent building surfaces is greater than the thickness of the walls (102) and roofs inside the adjacent building surfaces.

4. The nuclear power plant structure according to claim 3, characterized in that: The thickness of the wall (102) and the roof in the first type of factory building (100) is reduced according to the angle of impact resistance.

5. The nuclear power plant structure according to claim 4, characterized in that: The vibration sensitive equipment in the first-class factory building (100) and the second-class factory building (200) is arranged away from the wall (102) and the roof that resist impact, and a partition is provided on the vibration transmission path between the vibration sensitive equipment and the wall (102) and the roof.

6. The nuclear power plant structure according to claim 3, characterized in that: The wall (102) of the adjacent building surfaces is also formed between two adjacently arranged first-type factory buildings (100) or two adjacent second-type factory buildings (200).

7. The nuclear power plant structure according to claim 6, characterized in that: Between the first-class factory building (100) and the second-class factory building (200), between two first-class factory buildings (100), and between two second-class factory buildings (200) within the adjacent building surfaces, a wall (102) of the first-class factory building (100) or the second-class factory building (200) is shared.

8. The nuclear power plant structure according to claim 1, characterized in that: The first type of factory building (100) and the second type of factory building (200) are arranged on the same common raft foundation.

9. The nuclear power plant structure according to claim 8, characterized in that: In the adjacent building surface, the outer containment shell (101) of the first-class factory building (100) and the wall (102) of the adjacent building surface are connected to each other below the reference plane and are disconnected from each other above the reference plane.

10. The nuclear power plant structure according to claim 9, characterized in that: In the adjacent building surface, the outer containment shell (101) of the first type of factory building (100) and the wall (102) of the adjacent building surface are partially connected to each other above the reference plane and are disconnected from each other at another part.

11. The nuclear power plant structure according to claim 8, characterized in that: In the adjacent building surface, the outer containment shell (101) of the first-class factory building (100) is completely connected to the wall (102) of the adjacent building surface.

12. The nuclear power plant structure according to claim 8, characterized in that: The outer containment shell (101) of the first-class factory building (100) and the wall (102) of the adjacent building surface are separated from each other above the common raft foundation.

13. The nuclear power plant structure according to any one of claims 9, 10 or 12, characterized in that: A protective structure is also arranged between the mutually disengaged adjacent building surfaces, and the protective structure covers the mutually disengaged area to prevent debris from entering between the adjacent building surfaces.

14. The nuclear power plant structure according to claim 1, characterized in that: It also includes a deployed fire partition barrier, which meets the fire resistance limit requirements of the first-class factory building (100) or the second-class factory building (200).

15. The nuclear power plant structure according to claim 1, characterized in that: The outer containment (101) and the wall (102) of the first-class factory building (100) are provided with inner lining or outer hanging protection.

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