A potential energy-based structural self-rotation shock-resistant layer for seismic isolation of nuclear power plants

Abstract

The present invention belongs to the field of earthquake and impact safety of nuclear power plants, and specifically discloses a new type of nuclear power plant with a potential energy-based self-rotating shock-resistant interlayer seismic isolation, including a nuclear island lower structure, a nuclear island upper structure, an interlayer seismic isolation layer, an excitation device and nuclear equipment, wherein the interlayer seismic isolation layer is connected between the nuclear island lower structure and the nuclear island upper structure, and includes a seismic isolation support, a roller track, a roller shaft, a roller, a spring pull rod, a braking device, an impact sensor, an air hole and a friction plate; the excitation device is distributed in a circular array on the inner wall of the nuclear island upper structure, and multiple layers are arranged at equal intervals above and below, and include a bottom plate, a side plate, a pre-tensioned spring, an impact mass block and a release control system. The present invention changes the traditional structure that adopts a resistance method to prevent aircraft impact damage to an energy conversion method to prevent aircraft impact damage, and at the same time utilizes rotation to deflect the impact direction represented by an aircraft, thereby reducing the transmission of impact energy to the structure.

Description

Technical Field

[0001] The invention relates to the field of earthquake and impact safety of nuclear power plants, in particular to a new type of nuclear power plant with potential energy-based structural self-rotation and impact-resistant interlayer seismic isolation. Background Art

[0002] Nuclear power generation is one of the clean, efficient and environmentally friendly energy sources, and is also a key development direction for my country's green energy. my country's 2021 "Government Work Report" mentioned "actively and orderly developing nuclear power on the premise of ensuring safety." "Ensuring safety" is the premise of "actively and orderly", mainly because nuclear power plant accidents can cause serious and long-term environmental pollution, major economic losses, and even serious social problems. Obviously, nuclear power plant safety is a key issue in nuclear power generation.

[0003] The safety of nuclear power plants has always been the focus of the development of the nuclear power plant industry. Therefore, the earthquake safety of nuclear power plants has always been the focus of research at home and abroad. Due to the complexity and uncertainty of earthquakes, it is difficult for current science and technology to accurately predict the time, location, magnitude and spectral characteristics of earthquakes. Japanese scholar Kawata Akira pointed out that even with the latest plate tectonic theory, it is impossible to obtain the seismic information necessary for building structure design. Academician Xie Lili also pointed out that many areas where strong earthquakes are not thought to be possible have experienced "unexpected earthquakes". For example, the 5.12 Wenchuan earthquake (M8.0) and the 3.11 Japan earthquake (M9.0) exceeded the design value. At the same time, the emergence of new potential earthquake faults will also affect the seismic safety of nuclear power plants. For example, Unit 1 of the Hamaoka Nuclear Power Plant in Japan was threatened by the potential threat of the Tokai Fault, and the design earthquake was increased from 0.45g to 1.0g. Due to the discovery of the new Hos-Gri fault, the design earthquake of the Diablo Canyon Nuclear Power Plant of PG&E in California, USA, was increased from 0.4g to 0.75g. At the same time, in the past decade, nuclear accidents related to earthquakes in Japan include: On August 16, 2005, the Onagawa Nuclear Power Plant suffered an earthquake exceeding the design S1 level, which shut down the reactor for 23 months; On March 25, 2007, the Yokogawa Nuclear Power Plant suffered an earthquake exceeding the design S1 level, which shut down the reactor for 14 months; In the same year, the Kariwa Nuclear Power Plant suffered an earthquake exceeding the design S2 level, causing water containing trace radioactive substances to leak and shut down the reactor for 24 months; On March 11, 2011, the Fukushima Nuclear Power Plant suffered the 9.0 magnitude 3.11 Japan earthquake, causing a magnitude 7 nuclear accident. On August 23, 2011, a 5.8 magnitude earthquake occurred on the east coast of the United States, causing 12 nuclear power plants near Virginia to feel the tremor, causing the shutdown of two nuclear reactors near the epicenter. Among them, the acceleration of the horizontal and vertical vibrations of the North Anna Nuclear Power Plant exceeded the design values. Although no nuclear accident occurred, cracks appeared in the walls inside the plant and the radioactive waste storage tanks also slipped. There is still a large gap between the seismic safety of traditional nuclear power plant structures and actual needs.

[0004] Passive seismic isolation and damping technology of structures meets the technical requirements of passive safety of third-generation nuclear power plants and is the development direction of seismic safety of nuclear power plant structures. Base isolated structure (BIS) has the advantages of high technical maturity, convenient use, effective isolation of seismic energy input to the upper structure of the nuclear island, reduction of structural seismic response, and reduction of structural seismic damage. It has been successfully applied to civil, transportation, bridge and other fields. However, due to the safety issues of nuclear equipment faced by base isolated nuclear power plants, the nuclear industry maintains a cautious attitude towards BIS NPPs. However, due to the key issues faced by BIS nuclear power plants: ① BIS structure is sensitive to sliding, pulse near-field and long-period earthquakes, and there is a risk of structural seismic failure under such earthquakes; ② The seismic displacement of the isolation bearing is large, which increases the risk of fracture of the connecting pipeline between the isolation part and the non-isolation part, and there is a hidden danger of failure of nuclear safety function; ③ BIS structure amplifies the seismic response of long-period structure and fluid sloshing mode, and increases the risk of seismic damage to key nuclear equipment, such as pressure vessels and piping systems; Therefore, the nuclear industry has adopted a cautious attitude towards BIS nuclear power plants. Obviously, studying the key issues facing BIS nuclear power plants has important research value.

[0005] In response to the problems existing in BIS nuclear power plants, domestic and foreign scholars have conducted a lot of research and achieved fruitful research results. Foreign scholars such as Italy's Forni, South Korea's Yoo and the United States' Whittaker, as well as my country's academicians Xie Lili, Zhou Fulin, Kong Xianjing and Lin Gao have advocated and applied seismic isolation technology to improve the seismic safety of nuclear power plants, and strived to solve the key problems that restrict base-isolated nuclear power plants. The landmark achievements are: ① In view of the sensitivity of base-isolated structures to sliding-type, pulse-type near-field, and long-period earthquake motions, Academician Xie Lili proposed to reduce the adverse effects of such earthquakes on base-isolated nuclear power plants through super-benchmark earthquake design; ② In view of the large relative displacement of the isolation layer, which increases the risk of fracture of the connecting pipes between the isolation part and the non-isolation part of the nuclear power plant, Forni proposed to use technical measures such as large deformation expansion nodes to alleviate the adverse effects of this factor. However, there is still a lack of in-depth research on problem ③. Xia Zufeng, Hou Gangling and others explored III +Based on the structural characteristics of the next-generation nuclear power reactor, the air intake of the passive safety function system of the nuclear power plant is applied. While maintaining the other parts of the structure unchanged, only the fixed connection between the nuclear island upper structure and the nuclear island lower structure of the air intake is replaced with a seismic isolation bearing. It can also be considered that the seismic isolation bearing of the BIS structure is moved upward from the foundation to the air intake at the top of the structure, forming a layered seismic isolation structure. At this time, the connecting pipe is located below the seismic isolation bearing, eliminating problem ②; the lower structure of the nuclear island belongs to the traditional non-seismic isolation structure, avoiding problem ③. At the same time, the structural optimization method is applied to better avoid the seismic failure of the structure. Since the structure meets the basic requirements of nuclear safety technology, has the advantages of clear shock absorption mechanism, simple and feasible implementation, etc., it has good application prospects.

[0006] Since the series of terrorist attacks on the World Trade Center in New York, USA on September 11, 2001, after the 9.11 incident, the U.S. Nuclear Regulatory Commission (NRC), China and the International Atomic Energy Agency have all regarded impact explosions as basic prevention and control events for nuclear power plant safety. The vibration characteristics of explosions can be described by three elements: amplitude, spectrum and duration. By comparing the three elements with and without a seismic isolation system, the impact of the explosion shock wave on the seismic isolation structure can be obtained. Whether in the vertical direction or the horizontal direction, the velocity peak-to-peak value of the experimental results with the seismic isolation system under the same amount of explosives is smaller than the velocity peak-to-peak value of the non-seismic isolation system; with the increase of the loading amount, the seismic isolation effect tends to be significant; the vibration peak-to-peak value in the horizontal direction is about 2 times larger than the peak-to-peak value in the vertical direction, and the seismic isolation structure has a similar vibration reduction effect in these two directions. Due to the different constraint stiffness in the horizontal and vertical directions, the vibration frequency in the vertical direction is high and the vibration amplitude in the horizontal direction is large. Whether it is vertical vibration or horizontal vibration, its main frequency is within 100HZ; vertical vibration has two main frequency areas, between 20-45HZ and between 55-75HZ, and the energy distribution of these two parts of frequency is equivalent. The main frequency of horizontal vibration is concentrated around 30HZ and presents a single-peak structure, indicating that horizontal vibration is mainly caused by low frequency, while vertical vibration has two main frequency areas. Whether in the vertical direction or the horizontal direction, the seismic isolation and vibration reduction system significantly reduces the amplitude of low-frequency vibration, which has a significant effect on structural shock absorption. However, under the action of direct impact load, the seismic isolation structure will produce large deformation or displacement, leading to accidents in nuclear power plants.

[0007] The isolation bearing of the general story isolation structure has a small stiffness, resulting in poor ability to resist aircraft impact and cannot meet the basic safety requirements for preventing aircraft impact accidents in nuclear power plants. At the same time, there is a new type of nuclear power plant structure with story isolation - rotation anti - impact. Relying on the eccentricity existing when the aircraft impacts the upper structure of the nuclear island, the impact energy is converted into the rotational kinetic energy of the upper structure of the nuclear island. However, due to the randomness of the aircraft impact, when the eccentricity existing when the aircraft impacts the upper structure of the nuclear island is small, the efficiency of the structure converting the impact energy into the rotational kinetic energy of the upper structure of the nuclear island is low. Summary of the Invention

[0008] The purpose of the present invention is to provide a new type of nuclear power plant with story isolation of structure self - rotation anti - impact based on potential energy to solve the problems raised in the above - mentioned background technology.

[0009] To achieve the above purpose, the present invention provides the following technical solution: A new type of nuclear power plant with story isolation of structure self - rotation anti - impact based on potential energy, including a lower structure of the nuclear island, an upper structure of the nuclear island, a story isolation layer, an excitation device, and nuclear equipment. The nuclear equipment is installed in the lower structure of the nuclear island. The story isolation layer is connected between the lower structure of the nuclear island and the upper structure of the nuclear island, and it includes an isolation bearing, a roller track, a roller shaft, rollers, a spring pull rod, a braking device, an impact sensor, air holes, and friction plates. The excitation devices are distributed in an annular array on the inner wall of the upper structure of the nuclear island and are arranged in multiple layers at equal intervals up and down. It includes a bottom plate, side plates, pre - tensioned springs, impact mass blocks, and a release control system.

[0010] Further, the side plates and the bottom plate of the excitation device enclose a "C" - shaped structure. One side plate is vertically arranged on each side of each bottom plate, and the bottom plate is fixedly connected to the inner wall of the upper structure of the nuclear island. The side plates are vertically arranged and perpendicular to the inner wall of the upper structure of the nuclear island.

[0011] Further, a plurality of impact mass blocks are provided and are symmetrically distributed on the opposite faces of the two side plates on each bottom plate. The two impact mass blocks facing each other on the two side plates are connected by pre - tensioned springs. A release control system is respectively installed at the positions corresponding to each impact mass block on the side wall of the side plate, and each impact mass block is fixedly connected to the side plate under the control of the release control system. The release control system is composed of an upper impact sensor, an adsorption groove, and an electromagnet. The upper impact sensors are distributed on the outer sides of the two side plates, the electromagnets are symmetrically arranged on the opposite faces of the two side plates, and an adsorption groove for the electromagnet to embed is opened on the side of the impact mass block facing the side plate.

[0012] Furthermore, the seismic isolation bearings are evenly spaced between the lower structure of the nuclear island and the upper structure of the nuclear island, and their cross-section is an "I"-shaped structure, and their upper and lower surfaces are respectively fixedly connected to the opposite surfaces of the lower structure of the nuclear island and the upper structure of the nuclear island, and spring pull rods are arranged on both sides of each of the seismic isolation bearings, one end of the spring pull rods is hinged to the top surface of the lower structure of the nuclear island, and the other end is hinged to the bottom surface of the upper structure of the nuclear island.

[0013] Furthermore, the friction plates are evenly spaced and distributed on both sides of the interlayer seismic isolation layer. The upper end of the friction plate is fixedly connected to the upper structure of the nuclear island, and the lower end thereof is overlapped with the lower structure of the nuclear island.

[0014] Furthermore, the roller shaft is fixedly connected to the upper surface of each seismic isolation support, and the roller sleeve is arranged on the roller shaft and can rotate around the roller shaft.

[0015] Furthermore, six rollers are arranged on the top of each of the seismic isolation supports and are arranged in a 2*3 pattern.

[0016] Furthermore, two roller tracks are provided and distributed on the inner and outer sides of the bottom surface of the nuclear island upper structure. The rollers are engaged with the corresponding roller tracks so that the nuclear island upper structure can rotate on the rollers along the roller tracks.

[0017] Furthermore, braking devices and impact sensors are provided on both sides of the roller. When not impacted, the braking device restricts the roller so that it cannot rotate. When the upper structure of the nuclear island is impacted, the impact sensor senses and triggers the release of the braking device, allowing the roller to rotate around the roller axis.

[0018] Furthermore, the air holes are arranged between the friction plates to meet the exhaust pressure requirement.

[0019] Compared with the prior art, the present invention has the following beneficial effects:

[0020] 1. The present invention changes the traditional structure's resistance method to prevent aircraft impact damage to an energy conversion method, that is, by rotating the upper layer isolation structure, the impact energy is converted into rotational kinetic energy.

[0021] 2. When the structure is hit by an aircraft, the upper structure of the nuclear island rotates to deflect the impact of the aircraft and reduce the transfer of impact energy to the structure.

[0022] 3. Add an excitation device to allow the upper structure of the nuclear island to produce an initial rotation when the structure is impacted, increase the initial eccentricity when the aircraft hits, and enhance the effect of the structure in converting impact energy into rotational kinetic energy and deflecting the direction of the aircraft impact.

[0023] 4. When the upper structure of the nuclear island rotates, the lower structure of the nuclear island is stationary. The displacement difference between the upper structure of the nuclear island and the lower structure of the nuclear island is used to reduce shock through the friction plate, and the rotational kinetic energy is converted into frictional heat energy for release.

[0024] In summary, the present invention utilizes an excitation device to convert the elastic potential energy stored in the pre-tensioned spring into the rotational kinetic energy of the upper structure of the nuclear island, thereby deflecting the movement direction of impact objects such as aircraft through the rotational movement process of the circular planar structure by applying the centrifugal force and the characteristics of linear motion, thereby reducing the transmission of energy to the upper structure of the nuclear island; at the same time, the eccentric impact of the impact object on the upper structure of the nuclear island will further drive the structure to rotate, and ultimately the direction of movement will deviate from the nuclear island, and with the help of the eccentricity formed after the deflection of the movement direction of the impact object, the impact transmitted to the upper structure of the nuclear island is converted into rotational kinetic energy, thereby reducing the interlayer seismic bearing. While bearing the shear force, it further reduces the impact energy transferred to the structure; the relative movement between the upper structure of the nuclear island and the lower structure of the nuclear island generated during the rotation is used to convert the rotational kinetic energy into frictional heat energy through the friction plate, and finally, the impact energy of the aircraft is converted into frictional heat energy; at the same time, the braking system is used to stop the movement of the upper structure of the nuclear island, and the braking system is combined with the spring pull rod to avoid the rolling of the roller and the relative displacement of the upper structure of the nuclear island, thereby ensuring the shock-absorbing effect of the interlayer seismic isolation structure. Therefore, when subjected to wind loads or earthquakes, the shock-absorbing characteristics of the interlayer seismic isolation structure will not be affected. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a structural cross-sectional view of the present invention.

[0026] Figure 2 It is a schematic diagram of pore distribution of the present invention;

[0027] Figure 3 For the present invention Figure 1 AA section view;

[0028] Figure 4 For the present invention Figure 1 BB cross-section diagram;

[0029] Figure 5 is a cross-sectional view of the seismic isolation support of the present invention;

[0030] Figure 6 For the present invention Figure 5 CC profile of ;

[0031] Figure 7 It is a detailed diagram of position E in the braking state of the present invention;

[0032] Figure 8 It is a detailed diagram of position E in the motion state of the present invention;

[0033] Fig. 9 For the present invention Figure 4 Refinement diagram at F in the middle;

[0034] Fig.10 is a three-dimensional diagram of the excitation device of the present invention;

[0035] Fig.11 A top view of the excitation device of the present invention;

[0036] Fig.12 Schematic diagram of the release control system of the present invention Figure 1 ;

[0037] Fig.13 Schematic diagram of the release control system of the present invention Figure 2 .

[0038] In the figure: 1. Lower structure of nuclear island; 2. Upper structure of nuclear island; 3. Interlayer seismic isolation layer; 301. Seismic isolation support; 302. Roller track; 303. Roller shaft; 304. Roller; 305. Spring pull rod; 306. Braking device; 307. Impact sensor; 308. Air hole; 309. Friction plate; 4. Excitation device; 401. Bottom plate; 402. Side plate; 403. Pre-tension spring; 404. Impact mass block; 405. Release control system; 4051. Upper impact sensor; 4052. Adsorption trough; 4053. Electromagnet; 5. Nuclear equipment. DETAILED DESCRIPTION

[0039] 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.

[0040] In the description of the present invention, it should be noted that the terms "vertical", "up", "down", "horizontal", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0041] In the description of the present invention, it should also be noted that, unless otherwise clearly specified and defined, the terms "set", "installed", "connected", and "coupled" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0042] Please refer to Figure 1-13 , the present invention provides a technical solution: a novel nuclear power plant with a structure self-rotating anti-shock layer isolation based on potential energy, including a lower structure 1 of the nuclear island, an upper structure 2 of the nuclear island, a layer isolation layer 3, an excitation device 4, and nuclear equipment 5. The nuclear equipment 5 is installed inside the lower structure 1 of the nuclear island. The layer isolation layer 3 is connected between the lower structure 1 of the nuclear island and the upper structure 2 of the nuclear island, and it includes a seismic isolation bearing 301, a roller track 302, a roller shaft 303, rollers 304, a spring tie rod 305, a braking device 306, a shock sensor 307, air holes 308, and friction plates 309. The excitation device 4 is distributed in an annular array on the inner wall of the upper structure 2 of the nuclear island, and multiple layers are arranged at equal intervals up and down. It includes a bottom plate 401, side plates 402, a pre-tensioned spring 403, a shock mass 404, and a release control system 405.

[0043] As Figure 10-13 shown, the side plates 402 and the bottom plate 401 of the excitation device 4 enclose a "C"-shaped structure. A side plate 402 is vertically arranged on each side of each bottom plate 401. The bottom plate 401 is fixedly connected to the inner wall of the upper structure 2 of the nuclear island. The side plates 402 are vertically arranged and perpendicular to the inner wall of the upper structure 2 of the nuclear island.

[0044] Furthermore, a plurality of shock masses 404 are provided and symmetrically distributed on the opposite surfaces of the two side plates 402 on each bottom plate 401. The two shock masses 404 facing each other on the two side plates 402 are connected by a pre-tensioned spring 403. A release control system 405 is installed at the corresponding position of each shock mass 404 on the side wall of the side plate 402, and each shock mass 404 is fixedly connected to the side plate 402 under the control of the release control system 405. The release control system 405 is composed of an upper shock sensor 4051, an adsorption groove 4052, and an electromagnet 4053. The upper shock sensors 4051 are distributed on the outer surfaces of the two side plates 402. The electromagnets 4053 are symmetrically arranged on the opposite surfaces of the two side plates 402. An adsorption groove 4052 for the electromagnet 4053 to be embedded is provided on the side of the shock mass 404 facing the side plate 402. The on-off of the circuit of the electromagnet 4053 is uniformly controlled by a controller.

[0045] When the upper structure 2 of the nuclear island is subjected to a large impact, the upper impact sensor 4051 sends a signal according to the direction of the impact, so that the electromagnet 4053 corresponding to the impact mass block 404 on one side is powered off and released from the side plate 402, as follows: when the impact is biased in the clockwise direction, the upper impact sensor 4051 sends a signal, triggering the controller to power off the electromagnet 4053 on the left side, releasing the constraint of the impact mass block 404 on the left side, and under the traction of the pre-tensioned spring 403, the impact mass block 404 hits the impact mass block 404 on the other side in the clockwise direction; multiple excitation devices 4 work together to form a clockwise direction. The force couple in the counterclockwise direction drives the nuclear island upper structure 2 to generate an initial clockwise rotation along the roller track 302; when the impact is biased in the counterclockwise direction or in the normal direction, the upper impact sensor 405 sends a signal, triggering the controller to cut off the power to the right electromagnet 4053, thereby releasing the constraint of the right impact mass block 404. Under the traction of the pre-tensioned spring 403, the impact mass block 404 hits the impact mass block 404 on the other side in the counterclockwise direction. The multiple excitation devices 4 work together to form a counterclockwise force couple, driving the nuclear island upper structure 2 to generate an initial counterclockwise rotation along the roller track 302.

[0046] The nuclear island upper structure 2 can be rotated relative to the nuclear island lower structure 1 by means of the excitation device 4, thereby achieving the purpose of improving the shock resistance of the nuclear power plant using interlayer seismic isolation technology by converting energy and reducing the transmission of impact energy to the structure.

[0047] like Figure 5 and Fig. 9 As shown, the seismic isolation bearings 301 are evenly spaced between the lower structure 1 of the nuclear island and the upper structure 2 of the nuclear island, and their cross-sections are in an "I"-shaped structure, and their upper and lower surfaces are respectively fixedly connected to the opposite surfaces of the lower structure 1 of the nuclear island and the upper structure 2 of the nuclear island, and spring pull rods 305 are arranged on both sides of each of the seismic isolation bearings 301, one end of the spring pull rods 305 is hinged to the top surface of the lower structure 1 of the nuclear island, and the other end is hinged to the bottom surface of the upper structure 2 of the nuclear island. The spring pull rod 305 is in a pre-tensioned state under normal conditions, tightening the nuclear island upper structure 2 and the nuclear island lower structure 1; when not impacted, since the horizontal stiffness of the spring of the spring pull rod 305 is much smaller than the vertical stiffness, the nuclear island upper structure 2 can have a larger displacement in the horizontal plane relative to the nuclear island lower structure 1 to meet the deformation requirements of the seismic isolation bearing 301; when impacted, the spring of the spring pull rod 305 is disconnected from the rod member to release the force on the structure, and the spring contraction will not affect the rotation of the nuclear island upper structure 2.

[0048] like Figure 4 , Figure 5 , Fig. 9As shown, the friction plates 309 are evenly spaced on both sides of the interlayer seismic isolation layer 3, the upper end of the friction plates 309 is fixedly connected to the nuclear island upper structure 2, and the lower end thereof is overlapped with the nuclear island lower structure 1. When the nuclear island upper structure 2 rotates, the lower part of the friction plates 309 and the nuclear island lower structure 1 are relatively displaced, thereby converting the rotational kinetic energy of the nuclear island upper structure 2 into frictional heat energy.

[0049] like Figure 6 As shown, the roller shaft 303 is fixedly connected to the upper surface of each seismic isolation support 301 , and the roller 304 is sleeved on the roller shaft 303 and can rotate around the roller shaft 303 .

[0050] Furthermore, six rollers 304 are arranged on the top of each of the seismic isolation supports 301 and are arranged in a 2*3 pattern.

[0051] like Figure 4 As shown, two roller tracks 302 are provided and are distributed on the inner and outer sides of the bottom surface of the nuclear island upper structure 2, and the rollers 304 and the corresponding roller tracks 302 are interlocked; Figure 5-7 As shown, the rollers 304 are in contact with the roller tracks 302 , so that the nuclear island superstructure 2 can rotate along the roller tracks 302 via the rollers 304 .

[0052] like Figure 7-8 As shown, braking devices 306 and impact sensors 307 are provided on both sides of the roller 304. When not impacted, the braking device 306 restricts the roller 304 so that it cannot rotate. When the nuclear island upper structure 2 is impacted, the impact sensor 307 senses and triggers the release of the braking device 306, so that the roller 304 can rotate around the roller axis 303. The braking device 306 is a brake, which is uniformly controlled by the controller.

[0053] like Figure 7 As shown, the air holes 308 are arranged between the friction plates 309 to meet the exhaust pressure requirement.

[0054] Specific:

[0055] Under normal conditions, the upper part of the isolation support is rigidly connected to the isolation support through the brake device, roller track and spring pull rod. The spring pull rod is arranged on both sides of the isolation support, and the lower part is hingedly connected to the upper surface of the lower structure of the nuclear island, and the upper part is hingedly connected to the lower surface of the upper structure of the nuclear island. At this time, the spring pull rod is in a pre-tensioned state, which can ensure that the inter-layer isolation layer part and the upper structure of the nuclear island are in a tightly connected state, and prevent the vertical tensile damage of the structure. The roller transmits the pressure of the upper structure of the nuclear island to the lower structure of the nuclear island through the roller track and the isolation support to prevent the structure from being damaged by compression; the brake device is arranged on the upper surface of the isolation support and is located on both sides of the roller to prevent the roller and the upper structure of the nuclear island from relative movement; and the brake device cooperates with the roller track to transmit the shear force of the upper structure of the nuclear island to the isolation support to prevent damage caused by wind load; the structural bending damage and overturning damage are achieved through the combined action of the tension of the spring pull rod and the pressure transmitted by the roller.

[0056] Under the action of earthquake, the brake device is still in working state, preventing the roller and the upper structure of the nuclear island from moving relative to each other, ensuring that the roller transmits the pressure and horizontal shear force to the seismic isolation bearing; the spring pull rod transmits the seismic tension between the upper structure and the lower structure; the spring pull rod and the roller-seismic isolation bearing work together to prevent the structural bending failure and overturning failure; under the action of the horizontal shear force of the earthquake, the seismic isolation bearing needs to undergo a large shear deformation to play a shock-absorbing role. At this time, the spring pull rod is hinged with the upper surface of the lower structure of the nuclear island and the lower surface of the upper structure of the nuclear island to form a horizontal mechanism structure, avoiding large shear deformation of the seismic isolation bearing, but does not affect the transmission of tension through the spring pull rod. According to the dynamic characteristics of the upper structure of the nuclear island, the mass and stiffness of the pre-tension spring and the impact mass block in the excitation device are adjusted so that the excitation device will not affect the dynamic characteristics of the upper structure of the nuclear island.

[0057] Under the impact load, the impact sensor determines that when the impact load is small or acts on the lower structure of the nuclear island, the brake system and the spring pull rod are in working state, and the resistance method is adopted to prevent impact damage; when the impact load acting on the upper structure of the nuclear island is large, the brake device is closed and the spring pull rod is disconnected. The brake device and the spring pull rod will not hinder the rotation of the upper structure of the nuclear island, so that the upper structure of the nuclear island can rotate. At the same time, the upper impact sensor sends a signal according to the impact direction of the structure, so that the pre-tension spring is released from the side plate of the excitation device. When the impact direction is biased to the clockwise direction, the upper impact sensor on the left sends a signal to trigger the release of the pre-tension spring, driving the left impact mass block to hit the right impact mass block; when the impact direction is biased to the counterclockwise direction or along the normal direction, the upper impact sensor on the right sends a signal to trigger the release of the pre-tension spring, driving the right impact mass block to hit the left impact mass block. The excitation device is evenly arranged along the entire circle of the circular cross-section of the upper structure of the nuclear island. Multiple excitation devices work together to form a clockwise or counterclockwise force couple, driving the upper structure of the nuclear island to form an initial clockwise or counterclockwise rotation along the roller track. The upper structure of the nuclear island has a circular plane feature. When the upper structure of the nuclear island rotates, centrifugal force will be generated, and the linear motion characteristics of the object will be applied to deflect the direction of the impact object to a certain extent, reducing the transmission of impact energy to the structure. Part of the impact energy transmitted to the structure will be converted into rotational kinetic energy, further reducing the damage to the structure. During the rotational motion, the roller rotates around the roller axis at a fixed point. The roller under the circular upper structure of the nuclear island moves in the same direction around the roller axis, so that the impact energy acting on the upper structure of the nuclear island is converted into rotational kinetic energy. The roller track is arranged between the upper surface of the isolation support and the lower surface of the lower structure of the nuclear island to prevent the running rotation from deviating from the circular predetermined trajectory. In the state of rotational motion, relative movement between the upper structure of the nuclear island and the lower structure of the nuclear island will occur. Upper and lower friction plates are arranged on both sides of the isolation support. The upper part of the friction plate is fixed on the side of the upper structure of the nuclear island, and the lower part is overlapped on the side of the lower structure of the nuclear island. When the upper structure of the nuclear island rotates, the friction plate uses the displacement difference between the upper structure of the nuclear island and the lower structure of the nuclear island to convert the rotational kinetic energy of the upper structure of the nuclear island into friction energy.

[0058] This technical solution ensures the realization and operation of this new type of nuclear power plant under normal conditions, earthquake effects, and impact effects, achieving the expected goals.

[0059] It is worth noting that the entire device is controlled by a main control button. Since the device matched with the control button is a common device and belongs to the existing mature technology, its electrical connection relationship and specific circuit structure will not be described in detail here.

[0060] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A nuclear power plant with potential energy-based structural self-rotation shock-resistant interlayer seismic isolation, characterized in that: It includes the lower structure of the nuclear island (1), the upper structure of the nuclear island (2), the inter-story isolation layer (3), the excitation device (4) and the nuclear equipment (5). The nuclear equipment (5) is installed inside the lower structure of the nuclear island (1). The inter-story isolation layer (3) is connected between the lower structure of the nuclear island (1) and the upper structure of the nuclear island (2), and it includes isolation bearings (301), roller tracks (302), roller shafts (303), rollers (304), spring tie rods (305), braking devices (306), impact sensors (307), air holes (308) and friction plates (309); The excitation devices (4) are distributed in an annular array on the inner wall of the upper structure of the nuclear island (2), and are arranged in multiple layers at equal intervals up and down. It includes a bottom plate (401), side plates (402), pre-tensioned springs (403), impact mass blocks (404) and a release control system (405); The side plates (402) and the bottom plate (401) of the excitation device (4) enclose a "C"-shaped structure. One side plate (402) is vertically arranged on each side of each bottom plate (401). The bottom plate (401) is fixedly connected to the inner wall of the upper structure of the nuclear island (2), and the side plates (402) are vertically arranged and perpendicular to the inner wall of the upper structure of the nuclear island (2); A plurality of impact mass blocks (404) are provided and are symmetrically distributed on the opposite surfaces of the two side plates (402) on each bottom plate (401). The two impact mass blocks (404) facing each other on the two side plates (402) are connected by pre-tensioned springs (403). A release control system (405) is installed at the corresponding position of each impact mass block (404) on the side wall of the side plate (402), and each impact mass block (404) is fixedly connected to the side plate (402) under the control of the release control system (405); The release control system (405) is composed of an upper impact sensor (4051), an adsorption groove (4052) and an electromagnet (4053). The upper impact sensors (4051) are distributed on the outer surfaces of the two side plates (402). The electromagnets (4053) are symmetrically arranged on the opposite surfaces of the two side plates (402). An adsorption groove (4052) for the electromagnet (4053) to be embedded is formed on one side of the impact mass block (404) facing the side plate (402); The seismic isolation supports (301) are evenly spaced between the lower structure (1) and the upper structure (2) of the nuclear island, and their cross-section is an "I"-shaped structure, and their upper and lower surfaces are respectively fixedly connected to the opposite surfaces of the lower structure (1) and the upper structure (2) of the nuclear island. A spring pull rod (305) is arranged on both sides of each of the seismic isolation supports (301), one end of the spring pull rod (305) is hinged to the top surface of the lower structure (1) of the nuclear island, and the other end is hinged to the bottom surface of the upper structure (2) of the nuclear island; the friction plates (309) are evenly spaced on both sides of the inner and outer sides of the interlayer seismic isolation layer (3), the upper end of the friction plate (309) is fixedly connected to the upper structure (2) of the nuclear island, and the lower end of the friction plate (309) is fixedly connected to the upper structure (2) of the nuclear island. The roller shaft (303) is fixedly connected to the upper surface of each seismic isolation support (301), and the roller (304) is sleeved on the roller shaft (303) and can rotate around the roller shaft (303); brake devices (306) and impact sensors (307) are arranged on both sides of the roller (304). When not impacted, the brake device (306) restricts the roller (304) so ​​that it cannot rotate. When the nuclear island upper structure (2) is impacted, the impact sensor (307) senses and triggers the brake device (306) to release, so that the roller (304) can rotate around the roller shaft (303).

2. A nuclear power plant with potential energy-based structural self-rotation shock-resistant interlayer seismic isolation according to claim 1, characterized in that: Six rollers (304) are arranged on the top of each of the seismic isolation supports (301) in a 2*3 arrangement.

3. A nuclear power plant with potential energy-based structural self-rotation shock-resistant layer isolation according to claim 1, characterized in that: The roller tracks (302) are provided with two and are distributed on the inner and outer sides of the bottom surface of the nuclear island upper structure (2). The rollers (304) and the corresponding roller tracks (302) are mutually engaged, so that the nuclear island upper structure (2) can rotate on the rollers (304) along the roller tracks (302).

4. A nuclear power plant with potential energy-based structural self-rotation shock-resistant layer isolation according to claim 1, characterized in that: The air holes (308) are arranged between the friction plates (309) to meet the exhaust pressure requirement.

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