Tough containment structure with expansion membrane

Abstract

The invention discloses a tough containment structure with an expansion membrane, belongs to the technical field of nuclear power safety, and aims to solve the problem that accidents are easily caused by single failure performance when a load-resistance confrontation model is applied to a nuclear island containment. According to the scheme, in a normal state, the prestressed spring is in a compressed state; when the pressure in the steel containment is increased, accident high-pressure gas in the containment enters the annular cavity and the space 2 through the gas release valve, the pre-stress spring releases the pre-pressure, and the dome is lifted together; water in the cooling water tank enters the space 3, and the expansion film is expanded; the pressure intensity is reduced to reach an expansion state; then, the air release valve is closed, the water release valve is opened, water in the cooling water tank is released to the annular cavity and the space 2, and the interior of the steel safety shell is cooled through the steel safety shell; and after cooling and pressure reduction are completed, the prestressed spring shrinks, the dome descends, and the expansion membrane recovers and enters a recovery state.

Description

Technical Field

[0001] The invention relates to a tough containment structure with a capacity expansion membrane, belonging to the technical field of nuclear power safety. Background Art

[0002] The nuclear island containment is the outermost enclosure structure of the nuclear island plant and the last safety barrier for nuclear safety. If a serious accident occurs, it must effectively withstand the pressure and temperature of the accident inside the nuclear island and maintain good airtightness and accident containment capabilities. That is, in extreme environments such as strong winds, earthquakes, explosions, and nuclear accidents, it must ensure the safety of nuclear power plant personnel and the surrounding public, and ensure that the surrounding environment is not polluted by nuclear leakage that exceeds the allowable standard.

[0003] According to the structural system, the nuclear island containment can be divided into three types: reinforced concrete structure, prestressed concrete structure and steel structure. In order to reduce costs and construction difficulties, concrete containment was adopted and gradually developed. At present, the most commonly used in existing nuclear power plants is the prestressed concrete single-layer shell with steel lining. Although the nuclear power plant containment adopts the structural reliability analysis method, that is, it takes into account the uncertainty factors in the design, such as material properties, load changes, etc. Through this method, engineers can evaluate the reliability of the containment within the design life and ensure its performance under various uncertain conditions. However, due to its application of load-resistance confrontation model and method, it is based on single failure performance and cannot avoid the failure of a single failure mode causing serious accident consequences of nuclear power plants.

[0004] At present, nuclear island containment at home and abroad are designed using the load-resistance confrontation model. The load-resistance confrontation model is a basic physical model in structural engineering and civil engineering, which is used to describe the interaction and relationship between the structure under the action of external loads and the structural resistance. Plotting the load S and the resistance R and their probability distribution in the same coordinate system, the state equation G=RS can intuitively determine whether the structure is failed. When the resistance R is greater than the load S, the structure is in a safe state, that is, it can work normally; when the resistance R is less than the load S, the structure is in a failed state, that is, the structure cannot work normally; when the resistance R is equal to the load S, the structure is in a safety limit state, that is, in the limit working state, that is, the above area is called the interference zone of load S and resistance R. Since the factors affecting the load S and resistance R are random, that is, the main influencing factors of the generalized load S are the external load, the geometric shape and size of the structure, the physical properties of the material, etc.; the main influencing factors of the generalized resistance R are the mechanical properties of the material, the process method and the use environment, etc. That is, both load S and resistance R are random variables in a probability distribution state. The generalized load S is the load that causes failure, and the generalized resistance R is the ability to resist failure. Obviously, the load-resistance confrontation model is based on a single state equation and does not have the ability to reflect the structure's recovery to other equilibrium safety states.

[0005] The contradiction between the single steady state of the load-resistance confrontation model and the study of multiple stable states of complex systems is becoming increasingly prominent. Based on the fact that there are multiple stable equilibrium states in the ecosystem, Berkes and Falk proposed that the system can have multiple equilibrium states, that is, external disturbances cause the system to transform from one equilibrium state to another equilibrium state. Based on this, ecological resilience was proposed. The word resilience comes from the Latin word Re-silio (Re = back, go back; Silio = to leap, jump), which means the action of jumping back. In the mid-19th century, resilience was successfully applied to the field of mechanical engineering to describe the ability of mechanical structures to return to their original state after external forces acted on them, and gradually developed into the theory of engineering resilience. In view of the fact that engineering resilience only has a single steady state, which is inconsistent with the fact that the ecosystem has multiple stable states, Holling studied the recovery capacity of the ecosystem in 1973, that is, the ecosystem evolves from one equilibrium state to another under the action of external disturbances, and developed ecological resilience into engineering resilience. In 1998, Berkes applied ecological resilience to study human social phenomena and found that ecological resilience only reflects the equilibrium state and cannot reflect the complexity of social evolution. Based on this, in 2004, Walker and other scholars described the dynamic process of change, adaptation and transformation of society under pressure and constraints, and proposed evolutionary resilience. The third United Nations Conference on Disaster Reduction in 2015 defined resilience as: the ability of a system, community or society exposed to hazards to resist, absorb, adapt to disaster impacts and recover from disasters in a timely and effective manner by protecting and restoring important basic structures and functions. Obviously, evolutionary resilience has become a development trend in the study of the safety performance of complex systems. Summary of the invention

[0006] Aiming at the problem that the nuclear island containment application load-resistance confrontation model is prone to cause accidents due to single failure performance, the present invention provides a tough containment structure with an expansion membrane.

[0007] The flexible containment structure with expansion membrane of the present invention comprises a containment cylinder 1, a dome 2, a steel containment 3, a gas relief valve 4, a prestressed spring 5, a cooling water tank 6, an expansion membrane 7 and a water relief valve 8;

[0008] The steel containment shell 3 is attached to the inner wall of the containment shell cylinder 1 and forms a roof structure at the top opening of the containment shell cylinder 1; the dome 2 is slidably connected to the top opening of the containment shell cylinder 1, and the expansion membrane 7 is fixedly connected to the top opening of the containment shell cylinder 1 and stacked on the top of the dome 2;

[0009] The annular cavity formed by the dome 2 and the containment shell 1 in the sliding connection section serves as a cooling water tank 6, which is replenished with water from the outside as needed; an annular cavity 9 is formed below the cooling water tank 6 and between the outer wall of the steel containment shell 3 and the containment shell 1;

[0010] A plurality of longitudinally retractable prestressed springs 5 ​​are arranged along the circumferential direction between the bottom end of the dome 2 and the top end of the containment shell 1;

[0011] A gas relief valve 4 is provided on the side wall of the steel containment shell 3 at the connection between the dome 2 and the containment shell cylinder 1. The gas relief valve 4 serves as a passage for gas flow in the containment shell and is used for atmospheric balance between the inside of the containment shell and the annular cavity 9.

[0012] A drain valve 8 is provided between the cooling water tank 6 and the annular cavity 9, for draining the water in the cooling water tank 6 into the annular cavity 9;

[0013] Under normal conditions, the water discharge valve 8 is closed, the prestressed spring 5 is in a compressed state, and the annular cavity 9 is empty; the air discharge valve 4 is closed, and the interior of the steel containment shell 3 is not connected to the annular cavity 9; the expansion membrane 7 is attached to the top of the dome 2;

[0014] When the pressure in the steel containment 3 increases, the air relief valve 4 opens, and the accident high-pressure gas in the containment enters the annular cavity 9 and the space 2 between the steel containment 3 and the dome 2 connected thereto through the air relief valve 4. The prestressed spring 5 releases the prestress, and together lifts the dome 2 to make it slide upward along the side wall of the containment cylinder 1; the water in the cooling water tank 6 enters the space 3 between the expansion membrane 7 and the dome 2, and the expansion membrane 7 is stretched open; the capacity of the containment increases, and the pressure decreases, reaching the expansion state;

[0015] Then, the air release valve 4 is closed, the water release valve 8 is opened, and the water in the cooling water tank 6 is released into the annular cavity 9 and the space 2. The cooling water and the hot air meet and condense in the space 2. The steel containment shell 3 serves as a heat transfer surface. The steam condenses on the inner and outer surfaces to release heat, thereby reducing the temperature and pressure and achieving a cooling layer flow state.

[0016] After the temperature and pressure are lowered, the prestressed spring 5 contracts, the dome 2 descends, and the expansion membrane 7 recovers, entering a recovery state.

[0017] Preferably, the top of the containment shell 1 has an outwardly convex sliding section, which includes a bottom ring 1-1, a sliding side wall 1-2 and a limit ring 1-3. The bottom ring 1-1 is connected between the top of the side wall of the containment shell 1 and the bottom of the sliding side wall 1-2. The upper inner wall of the sliding side wall 1-2 is provided with a limit ring 1-3.

[0018] The outer side wall of the bottom end of the dome 2 has an upper side ring 2-1 and a lower side ring 2-2;

[0019] In the normal state, the upper ring 2-1 is aligned and spliced ​​with the limit ring 1-3 to form a whole ring, and the lower ring 2-2 slides up and down along the sliding side wall 1-2. In the normal state, when the dome 2 is at the lower limit position, the annular cavity surrounded by the lower ring 2-2, the sliding side wall 1-2 and the upper side aligned and spliced ​​upper ring 2-1 and the limit ring 1-3 serves as a cooling water tank 6;

[0020] A prestressed spring 5 is arranged between the lower surface of the lower side ring 2 - 2 of the dome 2 and the upper surface of the bottom ring 1 - 1 of the containment shell 1 .

[0021] Preferably, the capacity expansion membrane 7 comprises a support layer 7-1, a sealing layer 7-2 and a radiation shielding layer 7-3; the support layer 7-1, the sealing layer 7-2 and the radiation shielding layer 7-3 are stacked in sequence.

[0022] Preferably, the steel containment shell 3 and the containment shell cylinder 1 are fixedly connected by welding.

[0023] Beneficial effects of the present invention:

[0024] The present invention adds a special membrane structure on the basis of the above-mentioned expandable containment with variable height of toughness, which is referred to as an expansion membrane in the present invention. The membrane has a multilayer structure, including a radiation shielding layer, a sealing layer and a supporting layer. The radiation shielding layer is used to block the penetration of radioactive particles, the sealing layer is used to ensure the sealing performance of the membrane, and the supporting layer is used to improve the mechanical strength and stability of the membrane. Therefore, the membrane structure selects materials with high density and radiation shielding ability as the main material, such as lead, tungsten or polymer lead. These materials can effectively block the penetration of radioactive particles and reduce the possibility of leakage. At the same time, considering that radioactive substances may be corrosive, the material of the membrane needs to have good corrosion resistance and be able to maintain stability and functionality under long-term contact with radioactive substances. The expansion membrane wraps the entire containment dome. When the containment is working normally, the expansion membrane is close to the outer surface of the dome, and the water tank part is folded and stacked on the top of the cooling water tank. When an accident occurs, the expansion membrane is opened to contain radioactive gases or used as a temporary water tank.

[0025] The present invention changes the traditional method of connecting the containment shell cylinder to give the containment shell an ecological resilience function. By using the prestressed spring and the accident pressure, the height of the containment shell is resiliently changed, and the volume of the containment shell is expanded in the accident state, thereby reducing the internal pressure of the containment shell. At the same time, the expansion membrane is expanded to prevent the leakage of radioactive substances. If the internal temperature of the containment shell exceeds the safety threshold when an accident occurs, the cooling water tank connected to the containment shell expansion membrane can be used to fill the outer surface of the containment shell with cooling water, forming a cooling layer to accelerate the cooling process. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1is a structural schematic diagram of a tough containment structure with an expansion membrane according to the present invention, which is in a normal working state 1;

[0027] Figure 2 is a schematic structural diagram of a tough containment structure with an expansion membrane according to the present invention, which is in an expansion state 2;

[0028] Figure 3 is a schematic structural diagram of a tough containment structure with an expansion membrane according to the present invention, which is in a cooling layer flow state 3;

[0029] Figure 4 is a schematic structural diagram of a tough containment structure with an expansion membrane according to the present invention, which is in a recovery state 4;

[0030] Figure 5 yes Figure 1 A partial enlarged view of

[0031] Figure 6 It is a schematic diagram of the structure of the expansion membrane. DETAILED DESCRIPTION

[0032] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0033] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments may be combined with each other.

[0034] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments, but they are not intended to limit the present invention.

[0035] Specific implementation method 1: The following is combined Figures 1 to 6 The present embodiment is described. The present embodiment describes a tough containment structure with an expansion membrane, comprising a containment cylinder 1, a dome 2, a steel containment 3, a gas relief valve 4, a prestressed spring 5, a cooling water tank 6, an expansion membrane 7 and a water relief valve 8;

[0036] The steel containment shell 3 is attached to the inner wall of the containment shell cylinder 1 and forms a roof structure at the top opening of the containment shell cylinder 1; the dome 2 is slidably connected to the top opening of the containment shell cylinder 1, and the expansion membrane 7 is fixedly connected to the top opening of the containment shell cylinder 1 and stacked on the top of the dome 2;

[0037] The annular cavity formed by the dome 2 and the containment shell 1 in the sliding connection section serves as a cooling water tank 6, which is replenished with water from the outside as needed; an annular cavity 9 is formed below the cooling water tank 6 and between the outer wall of the steel containment shell 3 and the containment shell 1;

[0038] A plurality of longitudinally retractable prestressed springs 5 ​​are arranged along the circumferential direction between the bottom end of the dome 2 and the top end of the containment shell 1;

[0039] A gas relief valve 4 is provided on the side wall of the steel containment shell 3 at the connection between the dome 2 and the containment shell cylinder 1. The gas relief valve 4 serves as a passage for gas flow in the containment shell and is used for atmospheric balance between the inside of the containment shell and the annular cavity 9.

[0040] A drain valve 8 is provided between the cooling water tank 6 and the annular cavity 9, for draining the water in the cooling water tank 6 into the annular cavity 9;

[0041] Under normal conditions, the water discharge valve 8 is closed, the prestressed spring 5 is in a compressed state, and the annular cavity 9 is empty; the air discharge valve 4 is closed, and the interior of the steel containment 3 is not connected to the annular cavity 9; the expansion membrane 7 is attached to the top of the dome 2, see Figure 1 As shown;

[0042] When the pressure in the steel containment 3 increases, the gas relief valve 4 opens, and the accident high-pressure gas in the containment enters the annular cavity 9 and the space 2 between the steel containment 3 and the dome 2 connected thereto through the gas relief valve 4. The prestressed spring 5 releases the prestress, and together lifts the dome 2 to make it slide upward along the side wall of the containment cylinder 1. Figure 2 As shown; the water in the cooling water tank 6 enters the space 3 between the expansion membrane 7 and the dome 2, and the expansion membrane 7 is expanded; the containment capacity increases, the pressure decreases, and reaches the expansion state, see Figure 3 As shown;

[0043] Then, close the air release valve 4, open the water release valve 8, and release the water in the cooling water tank 6 to the annular cavity 9 and the space 2. The cooling water and the hot air meet and condense in the space 2. The steel containment shell 3 serves as a heat transfer surface. The steam condenses on the inner and outer surfaces to release heat, achieving temperature and pressure reduction and reaching a cooling layer flow state. Figure 4 As shown;

[0044] After the temperature and pressure are lowered, the prestressed spring 5 contracts, the dome 2 descends, and the expansion membrane 7 recovers, entering a recovery state.

[0045] Space 1: inside the containment;

[0046] Space 2: between the steel containment 3 and the dome 2;

[0047] Space 3: between the expansion membrane 7 and the dome 2.

[0048] State 1: Figure 1 Normal state shown;

[0049] State 2: Figure 2 The dome is shown in an elevated state;

[0050] State 3: Figure 3 The expansion status shown;

[0051] State 4: Figure 4 The recovery status is shown.

[0052] See also Figure 5 As shown, the top of the containment shell 1 has an outwardly convex sliding section, which includes a bottom ring 1-1, a sliding side wall 1-2 and a limiting ring 1-3. The bottom ring 1-1 is connected between the top of the side wall of the containment shell 1 and the bottom of the sliding side wall 1-2, and the upper inner wall of the sliding side wall 1-2 is provided with a limiting ring 1-3;

[0053] The outer side wall of the bottom end of the dome 2 has an upper side ring 2-1 and a lower side ring 2-2;

[0054] In the normal state, the upper ring 2-1 is aligned and spliced ​​with the limit ring 1-3 to form a whole ring, and the lower ring 2-2 slides up and down along the sliding side wall 1-2. In the normal state, when the dome 2 is at the lower limit position, the annular cavity surrounded by the lower ring 2-2, the sliding side wall 1-2 and the upper side aligned and spliced ​​upper ring 2-1 and the limit ring 1-3 serves as a cooling water tank 6;

[0055] A prestressed spring 5 is arranged between the lower surface of the lower side ring 2 - 2 of the dome 2 and the upper surface of the bottom ring 1 - 1 of the containment shell 1 .

[0056] See also Figure 6 As shown, the capacity expansion film 7 includes a support layer 7-1, a sealing layer 7-2 and a radiation shielding layer 7-3; the support layer 7-1, the sealing layer 7-2 and the radiation shielding layer 7-3 are stacked in sequence.

[0057] The present invention adds a special membrane structure on the basis of the above-mentioned expandable containment with a variable height of toughness, which is called an expansion membrane in the present invention. The membrane has a multilayer structure, including a support layer 7-1, a sealing layer 7-2 and a radiation shielding layer 7-3. The radiation shielding layer 7-3 is used to block the penetration of radioactive particles, the sealing layer 7-2 is used to ensure the sealing performance of the membrane, and the support layer 7-1 is used to improve the mechanical strength and stability of the membrane. Therefore, the membrane structure selects materials with high density and radiation shielding ability as the main material, such as lead, tungsten or polymer lead. These materials can effectively block the penetration of radioactive particles and reduce the possibility of leakage. At the same time, considering that radioactive substances may be corrosive, the material of the membrane needs to have good corrosion resistance and can maintain stability and functionality in the case of long-term contact with radioactive substances. The expansion membrane wraps the dome 2 of the entire containment. When the containment is working normally, the expansion membrane 7 is close to the outer surface of the dome 2, and the cooling water tank 6 part is folded and stacked on the top of the cooling water tank 9. When an accident occurs, the expansion membrane 7 is opened to contain radioactive gases or used as a temporary water tank.

[0058] Production and installation process:

[0059] The specific implementation scheme of the present invention is basically the same as the traditional containment construction method. First, before the construction begins, it is necessary to select a construction site. After selecting a suitable site, the ground should be cleaned and leveled to ensure the safety and stability of the construction area. Only then can the construction of the nuclear containment be officially started.

[0060] After the construction area is determined, the basic construction work of the nuclear containment begins, which includes digging the foundation pit, pouring the concrete foundation, and setting up underground pipelines and cable channels.

[0061] While the above work is being carried out, the main containment shell and expansion membrane can be prefabricated in a specific factory according to the invention design, and transported to the construction site for assembly after the basic construction work is completed. During the assembly process, the quality and size of the components need to be strictly controlled to ensure that the final containment structure meets the design requirements.

[0062] According to the design requirements, the containment cylinder 1 required for concrete pouring is reasonably installed. After the containment cylinder 1 is installed, a layer of steel lining needs to be placed, assembled and welded layer by layer on the entire inner surface of the cylinder in sequence, so that the containment cylinder 1 and the steel containment 3 become a whole. A prestressed spring 5 is installed at the top of the containment cylinder 1, and the top of the prestressed spring 5 is welded to the reinforced concrete dome 2. The bottom of the steel containment 3 is welded to the containment cylinder 1, so that the steel containment becomes a continuous whole, and a gas relief valve 4 is installed at the elevation of the prestressed spring 5, and a water relief valve 8 is installed at the bottom of the reinforced concrete dome. Only the cylinder part of the steel containment is connected to the reinforced concrete containment cylinder body, and the dome part can be separated from the reinforced concrete dome to form a space 2, realizing the possibility of expansion of the containment. In addition to the bottom end of the reinforced concrete dome 2 being connected to the prestressed spring 5 by welding, the rest of the reinforced concrete dome 2 can move up and down with the expansion and contraction of the spring. During the movement of the reinforced concrete dome 2, the cooling water tank will change, so that the cooling water enters the space 3. Finally, a special expansion membrane 7 is installed on the outer surface of the reinforced concrete containment dome 2. The end of the expansion membrane 7 is firmly connected to the upper end of the containment cylinder 1, and sufficient expansion margin is reserved. When the dome 2 is lifted, cooling water enters the space 3, and the expansion membrane 7 is expanded. After the temperature and pressure are reduced, the expansion membrane 7 is restored. During the entire working project, the containment maintains the strength, air tightness and anti-radioactive material leakage function required by the project. The present invention also adds a new function of expandable toughness.

[0063] Workflow:

[0064] The present invention realizes the toughness function of the containment for special properties such as extremely high safety and disaster material containment by changing the containment cylinder structure and inventing a method of expanding the capacity membrane. When the pressure resistance reaches the expected safety threshold, the accident pressure is reduced by increasing the volume of the containment to achieve the transition from state 1 to state 2. When the temperature reaches the expected safety threshold, a cooling layer is formed on the outer surface of the steel containment 3 by opening the drain valve 8, achieving the transition from state 2 to state 3 to achieve the purpose of cooling. At the same time, the expansion membrane 7 ensures the sealing and accident containment functions of the containment, significantly improves the safety performance of the containment to prevent the leakage of radioactive materials, and opens up new technologies and methods for improving the containment of nuclear power plants and their disaster prevention performance.

[0065] The realization process mainly relies on a new connection method of the containment shell. Under normal working conditions, the prestressed spring 5 at the bottom of the dome 2 is in a compressed state, the dome 2 is close to the steel containment shell 3, and the expansion membrane 7 is close to the dome 2. If an accident occurs, the prestressed spring 5 will release the prestress and act on the containment shell dome 2 together with the accident pressure, so that the dome 2 is lifted, the height of the containment shell is increased, the volume is increased, and the pressure is reduced.

[0066] On the outer surface of the containment dome at the top of the water tank, there is an expansion membrane 7, which is a special membrane structure with three layers, namely, a radiation shielding layer, a sealing layer and a supporting layer. When the containment is working normally, the expansion membrane 7 is in close contact with the outer surface of the dome 2. When an accident occurs, the cooling water will expand the expansion membrane 7 to form a space 3 with the dome 2, which serves as a temporary container for the cooling water and forms a cooling flow layer, thereby increasing the contact area between the containment and the cooling water and accelerating the cooling speed after the containment accident occurs.

[0067] At the beginning of the accident, a large amount of energy is released into the containment, and the space 1 quickly heats up and increases in pressure. Heat conduction occurs on the surface of the steel containment 3, achieving a certain degree of cooling. The air relief valve 4 opens, hot air enters the space 2, and the accident pressure combined with the prestressed spring 5 lifts the dome 2 of the containment, and cooling water enters the space 3, the volume increases, and pressure reduction is achieved. The air relief valve 4 is closed, and the water relief valve 8 is opened, and the cooling water in the space 3 enters the space 2, and heat convection is achieved in the space 2. The steel containment 3 shell serves as a heat transfer surface, and the steam condenses on the inner surface to release heat, achieving the purpose of cooling. As the accident develops, the energy released into the containment gradually decreases, the cooling and decompression are completed, the spring contracts, the dome 2 and the expansion membrane 7 are restored, and the containment completes a working cycle. If the next accident occurs, the containment can still continue to work normally.

[0068] The present invention innovates a new design method based on the traditional containment, giving the containment model with the original single failure performance a new toughness function, so that the tough containment can actively change, adapt and change under the stimulation of pressure and restriction conditions. The expansion membrane cooperates with the expansion of the containment volume to achieve the new functions of cooling and reducing pressure and preventing the leakage of radioactive substances.

[0069] Although the present invention is described herein with reference to specific embodiments, it should be understood that these embodiments are merely examples of the principles and applications of the present invention. It should therefore be understood that many modifications may be made to the exemplary embodiments and that other arrangements may be devised without departing from the spirit and scope of the present invention as defined by the appended claims. It should be understood that the various dependent claims and features described herein may be combined in a manner different from that described in the original claims. It should also be understood that the features described in conjunction with a single embodiment may be used in other described embodiments.

Claims

1. A tough containment structure with an expansion membrane, characterized in that: It comprises a containment shell (1), a dome (2), a steel containment shell (3), a gas relief valve (4), a prestressed spring (5), a cooling water tank (6), an expansion membrane (7) and a water relief valve (8); The steel containment shell (3) is attached to the inner wall of the containment shell cylinder (1) and forms a roof structure at the top opening of the containment shell cylinder (1); the dome (2) is slidably connected to the top opening of the containment shell cylinder (1), and the expansion membrane (7) is fixedly connected to the top opening of the containment shell cylinder (1) and stacked on the top of the dome (2); The annular cavity formed by the dome (2) and the containment shell (1) in the sliding connection section serves as a cooling water tank (6), and the cooling water tank (6) is replenished with water from the outside as needed; an annular cavity (9) is formed below the cooling water tank (6) and between the outer wall of the steel containment shell (3) and the containment shell (1); A plurality of longitudinally retractable prestressed springs (5) are arranged along the circumferential direction between the bottom end of the dome (2) and the top end of the containment shell (1); A gas relief valve (4) is provided on the side wall of the steel containment shell (3) at the connection between the dome (2) and the containment shell cylinder (1), and the gas relief valve (4) serves as a passage for gas circulation in the containment shell and is used for atmospheric balance between the inside of the containment shell and the annular cavity (9); A drain valve (8) is provided between the cooling water tank (6) and the annular cavity (9) for draining water in the cooling water tank (6) into the annular cavity (9); Under normal conditions, the water discharge valve (8) is closed, the prestressed spring (5) is in a compressed state, and the annular cavity (9) is empty; the air discharge valve (4) is closed, and the interior of the steel containment vessel (3) is not connected to the annular cavity (9); the expansion membrane (7) is attached to the top of the dome (2); When the pressure in the steel containment (3) increases, the air relief valve (4) opens, and the accident high-pressure gas in the containment enters the annular cavity (9) and the space 2 between the steel containment (3) and the dome (2) connected thereto through the air relief valve (4). The prestressed spring (5) releases the prestress, and together they lift the dome (2) to make it slide upward along the side wall of the containment cylinder (1); the water in the cooling water tank (6) enters the space 3 between the expansion membrane (7) and the dome (2), and the expansion membrane (7) is expanded; the capacity of the containment increases, and the pressure decreases, reaching an expansion state; Then, the air release valve (4) is closed, and the water release valve (8) is opened, and the water in the cooling water tank (6) is released into the annular cavity (9) and the space 2. The cooling water and the hot air meet and condense in the space 2. The steel containment shell (3) serves as a heat transfer surface, and the steam condenses on the inner and outer surfaces to release heat, thereby achieving temperature reduction and pressure reduction, and reaching a cooling layer flow state; After the temperature and pressure are reduced, the prestressed spring (5) contracts, the dome (2) descends, and the expansion membrane (7) recovers, entering a recovery state.

2. A tough containment structure with an expansion membrane according to claim 1, characterized in that: The top end of the containment shell (1) is provided with an outwardly convex sliding section, the outwardly convex sliding section comprising a bottom ring (1-1), a sliding side wall (1-2) and a limiting ring (1-3), the bottom ring (1-1) being connected between the top end of the side wall of the containment shell (1) and the bottom end of the sliding side wall (1-2), and the upper inner wall of the sliding side wall (1-2) being provided with a limiting ring (1-3); The outer side wall of the bottom end of the dome (2) has an upper side ring (2-1) and a lower side ring (2-2); In a normal state, the upper ring (2-1) and the limit ring (1-3) are aligned and spliced ​​into a complete ring, and the lower ring (2-2) slides up and down along the sliding side wall (1-2). In a normal state, when the dome (2) is at the lower limit position, the annular cavity surrounded by the lower ring (2-2), the sliding side wall (1-2) and the upper aligned and spliced ​​upper ring (2-1) and the limit ring (1-3) serves as a cooling water tank (6); A prestressed spring (5) is arranged between the lower surface of the lower side ring (2-2) of the dome (2) and the upper surface of the bottom ring (1-1) of the containment shell (1).

3. A tough containment structure with an expansion membrane according to claim 2, characterized in that: The capacity expansion film (7) comprises a support layer (7-1), a sealing layer (7-2) and a radiation shielding layer (7-3); the support layer (7-1), the sealing layer (7-2) and the radiation shielding layer (7-3) are stacked in sequence.

4. A tough containment structure with an expansion membrane according to claim 1, characterized in that: The steel containment shell (3) and the containment shell cylinder (1) are fixedly connected by welding.

Images