Safety assessment method and device for ring crane in nuclear island plant

Abstract

The invention discloses a safety assessment method and device for a ring crane in a nuclear island plant, and the method comprises the following steps: obtaining the structural form of a containment vessel in the nuclear island plant, the structural form comprising a double-layer containment vessel and a single-layer containment vessel; when external impact occurs, if the containment vessel is a double-layer containment vessel, performing first vibration safety analysis on the ring crane in the nuclear island plant, and determining the safety of the ring crane according to a first vibration safety analysis result; and if the containment is a single-layer containment, performing second vibration safety analysis and dynamic response analysis on the ring crane, and comprehensively determining the safety of the ring crane according to a second vibration safety analysis result and a dynamic response analysis result. According to the method and the device, a standard process for analyzing the safety of the ring crane when the external impact occurs is given, so that a complex problem analysis process is standardized, the safety evaluation efficiency of the ring crane can be improved through the method and the device, and the analysis accuracy is ensured.

Description

Technical Field

[0001] The invention relates to the technical field of external event protection design of nuclear power plants, and in particular to a safety assessment method and device for a ring hoist in a nuclear island plant building. Background Art

[0002] The ring crane in the containment of a nuclear power plant is an important component of the nuclear power plant. It is installed on the containment through the bracket on the inner wall of the containment. Since the ring crane is directly connected to the containment, the large deformation of the containment under the impact of an aircraft will directly cause the ring crane to produce coordinated deformation. The ring crane runs directly above the nuclear island reactor. If the ring crane falls, it will cause extremely serious consequences. According to the design manual of the ring crane, the deformation index allowed during the acceptance of the ring crane is only a few millimeters. The impact condition of a large commercial aircraft belongs to a super-design basis event. When performing the impact calculation of a commercial aircraft, the containment is allowed to enter the nonlinear stage, which may cause the structural damage of the ring crane or the failure of the connection with the containment. The stress deformation of the ring crane under the impact of an aircraft and its safety performance need to be analyzed specifically. At present, the relevant research on aircraft impact nuclear power structures has been gradually improved, but the evaluation research on the response of equipment in nuclear power plants under the impact of aircraft is basically in a blank stage. The ring crane is a heavy equipment that spans the entire nuclear island plant. Its safety performance under various working conditions has been highly valued. Some related studies have systematically studied the safety of the ring crane under earthquake conditions and calibrated the calculation and analysis methods of the ring crane under earthquake conditions. However, the characteristics of aircraft impact loads are significantly different from earthquake loads. What kind of failure mode will the ring crane have under aircraft impact, and what kind of analysis model can be used to obtain accurate evaluation results, no relevant research has been carried out so far.

[0003] The existing patent CN110110357A discloses a commercial large aircraft impact event analysis and evaluation method for nuclear power plants, which includes the following steps: determine the evaluation object in combination with the specific design of the nuclear power plant; determine the aircraft impact condition; perform impact analysis and evaluation on the evaluation object according to different impact effect evaluation methods; determine the damage range caused by different impact effects; determine the failure of the system or equipment; perform impact consequence evaluation to determine whether all impact conditions can meet the overall acceptance criteria, if so, the evaluation is completed; if not, identify the design weaknesses, take necessary design enhancement measures, and re-analyze and evaluate. The patent does not propose how to conduct a safety assessment of the ring crane when the nuclear power plant is subjected to an external impact.

[0004] The existing literature compares the vibration of single-layer and double-layer containment nuclear island buildings under aircraft impact. In this literature, a refined finite element model of a reactor building with single-layer and double-layer containment is established, and the coupling method defined in NEI07-13 is used to compare the median acceleration time history and the peak value of the acceleration response spectrum at each main floor position of the single-layer and double-layer containment buildings under three impact conditions. Finally, based on the comparison results, the feasibility of optimizing the double-layer containment building to a single-layer containment building is evaluated from the perspective of vibration response. This literature also does not propose how to conduct a safety assessment of the ring hoist when a nuclear power plant is subjected to external impact.

[0005] In summary, neither of the above two documents proposes how to conduct a safety assessment of the ring crane when a nuclear power plant is subjected to an external impact. Summary of the invention

[0006] Based on the above technical problems, the present invention proposes a safety assessment method and device for a ring crane in a nuclear island plant.

[0007] To achieve the above object, the present invention proposes a safety assessment method for a ring crane in a nuclear island plant.

[0008] A safety assessment method for a ring crane in a nuclear island plant building, comprising:

[0009] Obtain the structural form of the containment in the nuclear island plant, which includes double-layer containment and single-layer containment;

[0010] In the event of an external impact, if the containment is a double-layer containment, the first vibration safety analysis is performed on the ring hoist in the nuclear island plant, and the safety of the ring hoist is determined based on the results of the first vibration safety analysis;

[0011] If the containment is a single-layer containment, a second vibration safety analysis and a dynamic response analysis are performed on the ring crane, and the safety of the ring crane is determined based on the results of the second vibration safety analysis and the dynamic response analysis.

[0012] Furthermore, a first vibration safety analysis is performed on the ring hoist in the nuclear island plant, and the safety of the ring hoist is determined according to the result of the first vibration safety analysis, including:

[0013] Conduct numerical simulation calculations on the process of the containment shell being subjected to external impact;

[0014] Obtaining the impact acceleration time history curve at the wheel from the numerical simulation calculation results, and converting the impact acceleration time history curve into an impact acceleration spectrum;

[0015] Determine whether the preset seismic response spectrum can envelop the impact acceleration spectrum;

[0016] If the preset seismic response spectrum can envelop the impact acceleration spectrum, it is determined that the ring hanger is safe in the event of an external impact;

[0017] If the preset seismic response spectrum cannot envelop the impact acceleration spectrum, a spectrum analysis is performed on the ring hanger according to the impact acceleration spectrum, and the safety of the ring hanger in the event of an external impact is determined based on the spectrum analysis results.

[0018] Furthermore, the safety of the ring crane in the event of an external impact is determined based on the spectrum analysis results, including:

[0019] If the spectrum analysis result of the ring hanger is that the stress level of the ring hanger components is in the plastic stage, then the time history analysis of the ring hanger is performed according to the acceleration time history curve at the wheel;

[0020] Determine whether the time history analysis results meet the preset first-category acceptance conditions;

[0021] If the time history analysis results meet the preset first-category acceptance conditions, it is determined that the ring crane is safe in the event of an external impact;

[0022] If the time history analysis results do not meet the preset first-category acceptance conditions, it is determined that the ring crane will fall when an external impact occurs.

[0023] Further, a spectrum analysis is performed on the ring crane according to the impact acceleration spectrum, and the safety of the ring crane when an external impact occurs is determined based on the spectrum analysis result, which also includes:

[0024] If the result of spectrum analysis on the ring hanger is that the stress levels of the ring hanger components are all in the elastic deformation stage, it is determined that the ring hanger is safe in the event of an external impact.

[0025] Furthermore, the time history analysis results include the deformation of the bridge main beam along the bridge main beam direction, the maximum deflection of the bridge main beam, the displacement time history curve at the bridge main beam, the displacement time history curve at the end beam, and the displacement time history curve at the maintenance frame. The preset first-class acceptance conditions include:

[0026] The deformation ΔL of the bridge girder along the bridge girder direction satisfies ΔL≤L / 100, where L is the length of the bridge girder.

[0027] And the maximum deflection h of the bridge girder satisfies h≤L / 200, where L is the length of the bridge girder.

[0028] The displacement change in the displacement time history curve at the main beam of the bridge is within the range of ±0.05L, and the displacement change in the displacement time history curve at the end beam is within the range of ±0.05L. 端 Within the range, the displacement change in the displacement time history curve at the maintenance frame is within ±0.05L 检 In the range, L 端 is the length of the end beam, L 检 is the length of the maintenance rack.

[0029] Furthermore, a second vibration safety analysis is performed on the ring crane, including:

[0030] Conduct numerical simulation calculations on the process of the containment shell being subjected to external impact;

[0031] Obtaining the impact acceleration time history curve and the impact displacement time history curve at the wheel from the numerical simulation calculation results, and converting the impact acceleration time history curve and the impact displacement time history curve into an impact acceleration spectrum and an impact displacement spectrum respectively;

[0032] Determine the cutoff frequency corresponding to the maximum displacement in the impact displacement time history curve in the impact displacement spectrum;

[0033] The acceleration spectrum greater than the cut-off frequency is intercepted, and the intercepted acceleration spectrum is used to perform a second vibration safety analysis on the ring crane.

[0034] Furthermore, the dynamic response analysis includes a first dynamic response analysis and a second dynamic response analysis. The first dynamic response analysis of the ring crane includes:

[0035] Conduct numerical simulation calculations on the process of the containment shell being subjected to external impact;

[0036] The first displacement time history curve of the ring beam when the external impact object hits the bridge main beam in a direction parallel to the bridge main beam is obtained from the numerical simulation calculation results;

[0037] Determine the deformation of the bridge main beam along the bridge main beam direction according to the first displacement time history curve of the ring beam;

[0038] Determine whether the deformation ΔL of the bridge frame main beam along the bridge frame main beam direction meets the preset second type acceptance conditions Wherein, L is the length of the bridge main beam, a is the peak acceleration of the impact position of the containment along the impact direction;

[0039] If the deformation of the bridge main beam along the bridge main beam direction meets the preset second type of acceptance conditions, the first dynamic response analysis result is that the bridge main beam will not be unstable as a whole and thus will not cause a falling accident;

[0040] If the deformation of the bridge frame main beam along the bridge frame main beam direction does not meet the preset second type of acceptance conditions, the result corresponding to the first dynamic response analysis is that the bridge frame main beam will become unstable as a whole and cause a falling accident.

[0041] Further, the deformation amount of the bridge frame main beam along the bridge frame main beam direction is determined according to the first displacement time history curve of the ring beam, including:

[0042] Obtain the maximum displacement of the ring beam at the impact position of the external impactor and the distance between the horizontal wheel and the ring beam from the first displacement time history curve of the ring beam;

[0043] According to the maximum displacement of the impact position of the external impactor and the distance between the horizontal wheel and the ring beam, the deformation of the bridge frame main beam along the bridge frame main beam direction is determined by Formula 1. Formula 1, ΔL=d-Δd, where d is the maximum displacement of the impact position of the external impactor, and Δd is the distance between the horizontal wheel and the ring beam.

[0044] Furthermore, the second dynamic response analysis of the ring crane is carried out, including:

[0045] The second displacement time history curve of the ring beam when the external impact object hits the bridge main beam in a direction perpendicular to the bridge main beam is obtained from the numerical simulation calculation results;

[0046] According to the second displacement time history curve of the ring beam, the maximum displacement of the ring beam along the impact direction parallel to the external impact object is obtained;

[0047] Determine whether the maximum displacement of the ring beam parallel to the impact direction of the external impactor meets the preset third-category acceptance conditions Where x is the maximum displacement of the ring beam parallel to the impact direction of the external impactor, H is the distance between the main beams of the bridge, and a x is the peak acceleration of the ring beam along the impact direction, g is the gravitational acceleration;

[0048] If the maximum displacement of the ring beam parallel to the impact direction of the external impactor meets the preset third-category acceptance condition, the second dynamic response analysis result is that the bridge main beam will not overturn and cause a fall accident;

[0049] If the maximum displacement of the ring beam along the impact direction parallel to the external impactor does not meet the preset third-category acceptance condition, the second dynamic response analysis result will be that the main beam of the bridge will overturn and cause a fall accident.

[0050] Further, including:

[0051] If the first dynamic response analysis result is that the main beam of the bridge frame will not lose stability as a whole and cause a falling accident, and the second dynamic response analysis result is that the main beam of the bridge frame will not overturn and cause a falling accident, then the dynamic response analysis result is that the ring crane will not fall in the event of an external impact.

[0052] Further, the safety of the ring crane is determined according to the second vibration safety analysis result and the dynamic response analysis result, including:

[0053] If the second vibration safety analysis result and the dynamic response analysis result both indicate that the ring crane will not fall, it is determined that the ring crane is safe in the event of an external impact.

[0054] To achieve the above-mentioned purpose, the present invention proposes a safety assessment device for a ring crane in a nuclear island plant.

[0055] A safety assessment device for a ring crane in a nuclear island plant, comprising:

[0056] An acquisition module is used to acquire the structural form of the containment in the nuclear island plant, which includes a double-layer containment and a single-layer containment;

[0057] The first analysis module is used for, when an external impact occurs, if the containment is a double-layer containment, performing a first vibration safety analysis on the ring hoist in the nuclear island plant, and determining the safety of the ring hoist according to the first vibration safety analysis result;

[0058] The second analysis module is used to perform a second vibration safety analysis and a dynamic response analysis on the ring crane if the containment shell is a single-layer containment shell, and determine the safety of the ring crane according to the second vibration safety analysis results and the dynamic response analysis results.

[0059] Furthermore, the first analysis module is used to:

[0060] Conduct numerical simulation calculations on the process of the containment shell being subjected to external impact;

[0061] Obtaining the impact acceleration time history curve at the wheel from the numerical simulation calculation results, and converting the impact acceleration time history curve into an impact acceleration spectrum;

[0062] Determine whether the preset seismic response spectrum can envelop the impact acceleration spectrum;

[0063] If the preset seismic response spectrum can envelop the impact acceleration spectrum, it is determined that the ring hanger is safe in the event of an external impact;

[0064] If the preset seismic response spectrum cannot envelop the impact acceleration spectrum, a spectrum analysis is performed on the ring hanger according to the impact acceleration spectrum, and the safety of the ring hanger in the event of an external impact is determined based on the spectrum analysis results.

[0065] Furthermore, the safety of the ring crane in the event of an external impact is determined based on the spectrum analysis results, including:

[0066] If the spectrum analysis result of the ring hanger is that the stress level of the ring hanger components is in the plastic stage, then the time history analysis of the ring hanger is performed according to the acceleration time history curve at the wheel;

[0067] Determine whether the time history analysis results meet the preset first-category acceptance conditions;

[0068] If the time history analysis results meet the preset first-category acceptance conditions, it is determined that the ring crane is safe in the event of an external impact;

[0069] If the time history analysis results do not meet the preset first-category acceptance conditions, it is determined that the ring crane will fall when an external impact occurs.

[0070] Further, a spectrum analysis is performed on the ring crane according to the impact acceleration spectrum, and the safety of the ring crane when an external impact occurs is determined based on the spectrum analysis result, which also includes:

[0071] If the result of spectrum analysis on the ring hanger is that the stress levels of the ring hanger components are all in the elastic deformation stage, it is determined that the ring hanger is safe in the event of an external impact.

[0072] Furthermore, the time history analysis results include the deformation of the bridge main beam along the bridge main beam direction, the maximum deflection of the bridge main beam, the displacement time history curve at the bridge main beam, the displacement time history curve at the end beam, and the displacement time history curve at the maintenance frame. The preset first-class acceptance conditions include:

[0073] The deformation ΔL of the bridge girder along the bridge girder direction satisfies ΔL≤L / 100, where L is the length of the bridge girder.

[0074] And the maximum deflection h of the bridge girder satisfies h≤L / 200, where L is the length of the bridge girder.

[0075] The displacement change in the displacement time history curve at the main beam of the bridge is within the range of ±0.05L, and the displacement change in the displacement time history curve at the end beam is within the range of ±0.05L. 端 Within the range, the displacement change in the displacement time history curve at the maintenance frame is within ±0.05L 检 In the range, L 端 is the length of the end beam, L 检 is the length of the maintenance rack.

[0076] Furthermore, a second vibration safety analysis is performed on the ring crane, including:

[0077] Conduct numerical simulation calculations on the process of the containment shell being subjected to external impact;

[0078] Obtaining the impact acceleration time history curve and the impact displacement time history curve at the wheel from the numerical simulation calculation results, and converting the impact acceleration time history curve and the impact displacement time history curve into an impact acceleration spectrum and an impact displacement spectrum respectively;

[0079] Determine the cutoff frequency corresponding to the maximum displacement in the impact displacement time history curve in the impact displacement spectrum;

[0080] The acceleration spectrum greater than the cut-off frequency is intercepted, and the intercepted acceleration spectrum is used to perform a second vibration safety analysis on the ring crane.

[0081] Furthermore, the dynamic response analysis includes a first dynamic response analysis and a second dynamic response analysis. The first dynamic response analysis of the ring crane includes:

[0082] Conduct numerical simulation calculations on the process of the containment shell being subjected to external impact;

[0083] The first displacement time history curve of the ring beam when the external impact object hits the bridge main beam in a direction parallel to the bridge main beam is obtained from the numerical simulation calculation results;

[0084] Determine the deformation of the bridge main beam along the bridge main beam direction according to the first displacement time history curve of the ring beam;

[0085] Determine whether the deformation ΔL of the bridge frame main beam along the bridge frame main beam direction meets the preset second type acceptance conditions Wherein, L is the length of the bridge main beam, a is the peak acceleration of the impact position of the containment along the impact direction;

[0086] If the deformation of the bridge main beam along the bridge main beam direction meets the preset second type of acceptance conditions, the first dynamic response analysis result is that the bridge main beam will not be unstable as a whole and thus will not cause a falling accident;

[0087] If the deformation of the bridge frame main beam along the bridge frame main beam direction does not meet the preset second type of acceptance conditions, the result corresponding to the first dynamic response analysis is that the bridge frame main beam will become unstable as a whole and cause a falling accident.

[0088] Further, the deformation amount of the bridge frame main beam along the bridge frame main beam direction is determined according to the first displacement time history curve of the ring beam, including:

[0089] Obtain the maximum displacement of the ring beam at the impact position of the external impactor and the distance between the horizontal wheel and the ring beam from the first displacement time history curve of the ring beam;

[0090] According to the maximum displacement of the impact position of the external impactor and the distance between the horizontal wheel and the ring beam, the deformation of the bridge frame main beam along the bridge frame main beam direction is determined by Formula 1. Formula 1, ΔL=d-Δd, where d is the maximum displacement of the impact position of the external impactor, and Δd is the distance between the horizontal wheel and the ring beam.

[0091] Furthermore, the second dynamic response analysis of the ring crane is carried out, including:

[0092] The second displacement time history curve of the ring beam when the external impact object hits the bridge main beam in a direction perpendicular to the bridge main beam is obtained from the numerical simulation calculation results;

[0093] According to the second displacement time history curve of the ring beam, the maximum displacement of the ring beam along the impact direction parallel to the external impact object is obtained;

[0094] Determine whether the maximum displacement of the ring beam parallel to the impact direction of the external impactor meets the preset third-category acceptance conditions Where x is the maximum displacement of the ring beam parallel to the impact direction of the external impactor, H is the distance between the main beams of the bridge, and ax is the peak acceleration of the ring beam along the impact direction, g is the gravitational acceleration;

[0095] If the maximum displacement of the ring beam parallel to the impact direction of the external impactor meets the preset third-category acceptance condition, the second dynamic response analysis result is that the bridge main beam will not overturn and cause a fall accident;

[0096] If the maximum displacement of the ring beam along the impact direction parallel to the external impactor does not meet the preset third-category acceptance condition, the second dynamic response analysis result will be that the main beam of the bridge will overturn and cause a fall accident.

[0097] Further, including:

[0098] If the first dynamic response analysis result is that the main beam of the bridge frame will not lose stability as a whole and cause a falling accident, and the second dynamic response analysis result is that the main beam of the bridge frame will not overturn and cause a falling accident, then the dynamic response analysis result is that the ring crane will not fall in the event of an external impact.

[0099] Further, the safety of the ring crane is determined according to the second vibration safety analysis result and the dynamic response analysis result, including:

[0100] If the second vibration safety analysis result and the dynamic response analysis result both indicate that the ring crane will not fall, it is determined that the ring crane is safe in the event of an external impact.

[0101] Based on the above technical solution, the present invention has at least the following beneficial effects:

[0102] 1. The present invention is based on the containment structure of the reactor building of a nuclear power plant and the transmission path of the impact when the containment is subjected to an external impact. Differentiated evaluation strategies are adopted for single-layer containment and double-layer containment. For the case where the reactor building has a double-layer containment, a vibration safety analysis of the ring hanger is carried out; for the case of a single-layer containment, a dynamic response analysis and a vibration safety analysis are carried out on the ring hanger respectively. The present invention provides a safety analysis process of the ring hanger under external impact to standardize the complex analysis process.

[0103] 2. When the present invention performs dynamic response analysis on the ring crane, the displacement time-history curves of the ring beam under different impact directions are extracted respectively according to the different external impact directions. The safety of the ring crane is comprehensively judged by judging whether the deformation of the bridge frame main beam along the main beam direction and the maximum displacement of the ring beam parallel to the impact direction meet multiple preset acceptance conditions. This method decouples the coupling problem and can ensure the accuracy of the analysis while improving the efficiency of the ring crane safety assessment.

[0104] 3. When analyzing the safety of the ring hanger in the single-layer containment, the present invention considers the dynamic response characteristics of the ring hanger during the impact process, and proposes to use the frequency corresponding to the macroscopic maximum displacement of the containment as the cutoff frequency to disassemble the acceleration spectrum, and then conduct vibration safety analysis and dynamic response analysis of the ring hanger respectively. This method and device can reduce the uncertainty and complexity in the analysis process, and designers can more intuitively understand the state of the ring hanger under external impact, thereby improving the accuracy and efficiency of the analysis. BRIEF DESCRIPTION OF THE DRAWINGS

[0105] The accompanying drawings constituting a part of the present invention are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the accompanying drawings:

[0106] Figure 1 A flow chart of a safety assessment method for a ring crane in a nuclear island plant building according to an embodiment of the present invention;

[0107] Figure 2 A schematic diagram of a path for the impact effect to be transmitted to the ring crane when a commercial aircraft hits a double-layer containment shell in one embodiment of the present invention;

[0108] Figure 3 A flow chart for conducting the first vibration safety analysis on the ring hoist in the nuclear island plant and determining the safety of the ring hoist based on the results of the first vibration safety analysis;

[0109] Figure 4 The overall structural diagram of the ring crane is shown in FIG.

[0110] Figure 5 for Figure 4 A magnified image of area A;

[0111] Figure 6 A schematic diagram of an impact acceleration spectrum of a specific embodiment of the present invention;

[0112] Figure 7 A schematic diagram of an impact acceleration spectrum of another specific embodiment of the present invention;

[0113] Figure 8 It is a schematic diagram of a displacement time-course variation curve that changes steadily in one embodiment of the present invention;

[0114] Fig. 9 This is a schematic diagram of the impact transmission when a commercial aircraft hits a single-layer containment shell;

[0115] Fig.10 Flow chart for the second vibration safety analysis of the ring crane when the aircraft hits the single-layer containment;

[0116] Fig.11A schematic diagram of an impact acceleration spectrum and an impact displacement spectrum of an embodiment of the present invention;

[0117] Fig.12 Schematic diagram of comparison of acceleration time history curves of a ring beam before and after filtering in one embodiment of the present invention;

[0118] Fig.13 A flow chart of performing a first dynamic response analysis on a ring crane in one embodiment of the present invention;

[0119] Fig.14 It is a schematic diagram of an external impact object impacting in a direction parallel to the main beam of the bridge frame;

[0120] Fig.15 A flow chart of performing a second dynamic response analysis on a ring crane in one embodiment of the present invention;

[0121] Fig.16 It is a schematic diagram of an external impact object impacting in a direction perpendicular to the main beam of the bridge frame;

[0122] Fig.17 The present invention is a schematic diagram of a safety assessment device for a ring crane in a nuclear island plant according to an embodiment of the present invention.

[0123] The above drawings include the following reference numerals:

[0124] 1. Bridge main beam; 2. Wheel; 3. Ring beam; 4. Horizontal wheel; 5. Double-layer containment outer shell; 6. Double-layer containment inner shell; 7. External impactor; 8. Ring crane; 9. Single-layer containment outer shell. DETAILED DESCRIPTION

[0125] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0126] The present invention is further described in detail below in conjunction with specific embodiments. These embodiments should not be construed as limiting the scope of protection claimed by the present invention.

[0127] Example

[0128] The ring crane of the nuclear island building is an important equipment located directly above the reactor. If a falling accident occurs, it will directly affect the reactor. When subjected to external impact, in addition to ensuring the functionality of the nuclear island building, it is also necessary to analyze the dynamic response of the ring crane to ensure that the ring crane does not fall. The present invention proposes a safety assessment method and device for the ring crane in the nuclear island building, and selects different assessment methods according to whether the reactor building of the nuclear power plant has a containment shell specially used to resist external impact objects. Specifically, the present invention proposes that for the case where the reactor building has two layers of containment shells, since the impact effect is not directly transmitted to the ring crane, it is sufficient to carry out a vibration safety analysis of the ring crane; for the case where the reactor building has only one layer of containment shell, the impact effect will be directly transmitted to the ring crane through the containment shell, and the ring crane needs to carry out dynamic response analysis and vibration safety analysis respectively.

[0129] To achieve the above object, the present invention proposes a safety assessment method for a ring crane in a nuclear island plant.

[0130] like Figure 1 A flow chart of a safety assessment method for a ring hoist in a nuclear island plant building according to an embodiment of the present invention is shown in FIG. 1 , and the flow chart includes the following steps:

[0131] S1, obtain the structural form of the containment in the nuclear island building.

[0132] The structural forms of the containment shell include a double-layer containment shell and a single-layer containment shell.

[0133] S2, when an external impact occurs, if the containment is a double-layer containment, a first vibration safety analysis is performed on the ring hoist in the nuclear island plant, and the safety of the ring hoist is determined based on the results of the first vibration safety analysis.

[0134] Figure 2The arrows around the middle containment shell indicate the path of the impact transmitted to the ring hanger when a commercial aircraft hits the double-layer containment. 5 represents the outer shell of the double-layer containment, 6 represents the inner shell of the double-layer containment, 7 represents the external impact object, and 8 represents the ring hanger. When the aircraft impacts the double-layer containment, the outer shell of the double-layer containment 5 directly resists the impact of the large commercial aircraft 7. Since the ring hanger 8 is fixed to the inner shell of the double-layer containment 6 through the bracket located in the inner containment, it will not be directly affected by the aircraft impact. However, the vibration effect of the aircraft impacting the outer shell of the double-layer containment 5 will be transmitted along the shell to the floor of the nuclear island plant, and then transmitted to the ring hanger 8 through the inner shell of the double-layer containment 6 connected to the floor, that is, the effect can be transmitted to the ring hanger through the path of shell → floor → shell. Considering that the aircraft impact is a high-frequency, instantaneous and violent impact load, the response near the direct impact position of the aircraft impact is relatively violent, and nonlinear analysis is required. However, the structural vibration response caused by the impact load will decay with the increase of the transmission distance. When the aircraft hits the double containment shell, the force transmission path to the ring hanger is long, so the safety analysis of the ring hanger can be carried out by decoupling the first vibration safety analysis. Figure 3 As shown, a first vibration safety analysis is performed on the ring hoist in the nuclear island plant, and the safety of the ring hoist is determined according to the result of the first vibration safety analysis, including the following sub-steps:

[0135] S201, performing numerical simulation calculation on the process of the containment being subjected to external impact.

[0136] S202, obtaining an impact acceleration time history curve at the wheel from the numerical simulation calculation result, and converting the impact acceleration time history curve into an impact acceleration spectrum.

[0137] like Figure 4 The overall structure diagram of the ring crane is shown in Figure 4 The main beam 1 of the bridge can be seen in the figure. Figure 5 for Figure 4 The enlarged view of area A in the middle Figure 5 Wheel 2, ring beam 3 and horizontal wheel 4 can be seen in the figure. There are four wheels in the ring beam, and the wheels are located below the main beam of the bridge frame. In this step, the impact acceleration time history curves in three directions at the four wheels are extracted, and then the impact acceleration time history curves are converted into impact acceleration spectra using the time history conversion spectrum method.

[0138] S203, determining whether the preset seismic response spectrum can envelop the impact acceleration spectrum.

[0139] S204: If the preset seismic response spectrum can envelop the impact acceleration spectrum, it is determined that the ring hanger is safe when an external impact occurs.

[0140] like Figure 6FIG. 1 shows a schematic diagram of an impact acceleration spectrum of a specific embodiment of the present invention, wherein L1 is a preset earthquake response spectrum and L2 is an impact acceleration spectrum. Figure 6 It can be seen that the preset seismic response spectrum can completely envelop the impact acceleration spectrum, which means that the effect of the aircraft impact on the ring crane is smaller than that of the earthquake. In this embodiment, the ring crane is safe when an external impact occurs.

[0141] S205: If the preset seismic response spectrum cannot envelop the impact acceleration spectrum, a spectrum analysis is performed on the ring hanger according to the impact acceleration spectrum, and the safety of the ring hanger when an external impact occurs is determined based on the spectrum analysis result.

[0142] like Figure 7 FIG. 2 shows a schematic diagram of an impact acceleration spectrum of another specific embodiment of the present invention, wherein L1 is a preset earthquake response spectrum and L2 is an impact acceleration spectrum. Figure 7 It can be seen that the preset seismic response spectrum cannot envelop the impact acceleration spectrum. It is necessary to perform a spectral analysis on the ring hanger according to the impact acceleration spectrum, and determine the safety of the ring hanger in the event of an external impact based on the spectral analysis results. If the result of the spectral analysis of the ring hanger is that the stress levels of the ring hanger components are all in the elastic deformation stage, that is, the effective stress of all the components of the ring hanger is less than the yield stress of the component material, it is determined that the ring hanger is safe in the event of an external impact. If the result of the spectral analysis of the ring hanger is that the stress levels of the ring hanger components are all in the plastic stage, and the effective stress of all the components of the ring hanger is greater than the yield stress of the component material, then further perform a time history analysis on the ring hanger to determine the safety of the ring hanger. Specifically, the process includes the following sub-steps:

[0143] S2051: If the spectrum analysis result of the ring hanger is that the stress levels of the ring hanger components are all in the plastic stage, then a time history analysis of the ring hanger is performed according to the acceleration time history curve at the wheel.

[0144] S2052, determining whether the time history analysis result meets the preset first type acceptance condition.

[0145] The ring beam is located below the ring crane wheel. The time history analysis results include the deformation of the bridge frame main beam along the bridge frame main beam direction, the maximum deflection of the bridge frame main beam, the displacement time history curve at the bridge frame main beam, the displacement time history curve at the end beam, and the displacement time history curve at the maintenance frame.

[0146] The preset first category acceptance conditions include: (1) the deformation ΔL of the bridge frame main beam along the bridge frame main beam direction satisfies ΔL≤L / 100, where L is the length of the bridge frame main beam, indicating that the ring-type suspension bridge frame main beam will not be compressed and unstable, thereby causing a falling accident; (2) the maximum deflection h of the bridge frame main beam satisfies h≤L / 200, where L is the length of the bridge frame main beam, indicating that the ring-type suspension bridge frame main beam will not be unstable, thereby causing a falling accident; (3) the displacement change in the displacement time-history curve at the bridge frame main beam is within the range of ±0.05L, and the displacement change in the displacement time-history curve at the end beam is within the range of ±0.05L 端 Within the range, the displacement change in the displacement time history curve at the maintenance frame is within ±0.05L 检 In the range of 端 is the length of the end beam, L 检 is the length of the maintenance rack. Figure 8 Two displacement time-history curves at the main beam of the bridge are shown in the figure. From the displacement time-history curve B, it can be seen that the displacement at the main beam of the bridge is constantly increasing, and the displacement change gradually exceeds the preset range of change; the displacement time-history curve C changes smoothly, and there is no trend of increasing displacement, and the displacement change is within the preset range of change.

[0147] S2053, if the time history analysis results meet the preset first-category acceptance conditions, it is determined that the ring crane is safe in the event of an external impact.

[0148] If the time history analysis result satisfies all conditions of the first type of acceptance conditions in step S2053, it is determined that the ring hanger is safe when an external impact occurs.

[0149] S2054: If the time history analysis result does not meet the preset first-category acceptance condition, it is determined that the ring crane will fall when an external impact occurs.

[0150] S3, if the containment shell is a single-layer containment shell, a second vibration safety analysis and a dynamic response analysis are performed on the ring crane, and the safety of the ring crane is determined according to the second vibration safety analysis results and the dynamic response analysis results.

[0151] like Fig. 9 The figure shows a schematic diagram of the state when a commercial aircraft hits a single-layer containment shell, wherein the arrow direction indicates the transmission path of the aircraft impact effect, 9 indicates the single-layer containment shell, 8 indicates the ring hanger, and 7 indicates the external impactor. Fig.10 As shown, the second vibration safety analysis of the ring crane includes the following sub-steps:

[0152] S301, performing numerical simulation calculation on the process of the containment being subjected to external impact.

[0153] S302, obtaining an impact acceleration time history curve and an impact displacement time history curve at the wheel from the numerical simulation calculation results, and converting the impact acceleration time history curve and the impact displacement time history curve into an impact acceleration spectrum and an impact displacement spectrum respectively.

[0154] Similar to the double-layer containment shell, when obtaining the impact acceleration time-history curve and the impact displacement time-history curve at the wheel, the impact acceleration time-history curves and the impact displacement time-history curves in three directions at the four wheels under the main beam of the bridge are extracted.

[0155] S303, determining a cutoff frequency corresponding to the maximum displacement in the impact displacement time history curve in the impact displacement spectrum.

[0156] S304, intercepting the acceleration spectrum greater than the cut-off frequency, and using the intercepted acceleration spectrum to perform a second vibration safety analysis on the ring crane.

[0157] like Fig.11 The impact acceleration spectrum and impact displacement spectrum of an embodiment of the present invention are shown in the figure, wherein the ordinate corresponding to the point M on the displacement spectrum is the maximum displacement in the impact displacement time history curve, that is, the macroscopic maximum displacement of the containment shell, and the corresponding abscissa is the cutoff frequency. The acceleration spectrum greater than the cutoff frequency in the impact acceleration spectrum is intercepted, and the intercepted acceleration spectrum is used to perform a second vibration safety analysis on the ring hanger. The process of the second vibration safety analysis is basically the same as the process of the first vibration safety analysis mentioned above, and will not be repeated here. It should be noted that in the process of performing the vibration safety analysis, if the spectrum analysis results show that the stress level of some components of the ring hanger has entered the plastic stage, it is necessary to extract the acceleration time history curve of the ring beam, and filter the acceleration time history curve at the critical frequency to filter the waveforms less than the critical frequency, and then perform a time history analysis of the ring hanger. Fig.12 2 shows the acceleration time history curve D of the ring beam extracted during the vibration safety analysis of the containment and the acceleration time history curve E after filtering.

[0158] After the above steps S301 to S304, the second vibration safety analysis is performed on the ring hanger, and the corresponding analysis results are obtained. The ring hanger will be subjected to a dynamic response analysis below. When the second vibration safety analysis result and the dynamic response analysis result both indicate that the ring hanger will not fall, it can be determined that the ring hanger is safe in the event of an external impact.

[0159] like Fig.13 As shown, the dynamic response analysis includes a first dynamic response analysis and a second dynamic response analysis. The first dynamic response analysis of the ring crane includes the following steps:

[0160] S310, performing numerical simulation calculation on a process in which the containment shell is subjected to external impact.

[0161] S311, obtaining, from the numerical simulation calculation results, a first displacement time history curve of the ring beam when an external impactor impacts along a direction parallel to the bridge main beam.

[0162] like Fig.14 The schematic diagram shows the impact of an external impact object in a direction parallel to the bridge main beam. Fig.14 9 represents the single-layer containment shell, and 7 represents the external impactor.

[0163] S312, determining the deformation of the bridge frame main beam along the bridge frame main beam direction according to the first displacement time history curve of the ring beam.

[0164] Furthermore, the deformation of the bridge frame main beam along the bridge frame main beam direction is determined according to the first displacement time history curve of the ring beam, including: first, obtaining the maximum displacement of the ring beam at the impact position of the external impactor and the distance between the horizontal wheel and the ring beam from the first displacement time history curve of the ring beam. Subsequently, according to the maximum displacement at the impact position of the external impactor and the distance between the horizontal wheel and the ring beam, the deformation of the bridge frame main beam along the bridge frame main beam direction is determined by formula 1, formula 1, ΔL = d-Δd, where d is the maximum displacement at the impact position of the external impactor, and Δd is the distance between the horizontal wheel and the ring beam.

[0165] S313, judging whether the deformation amount ΔL of the bridge frame main beam along the bridge frame main beam direction meets the preset second type acceptance condition.

[0166] The preset second type of acceptance conditions are: Wherein, L is the length of the bridge main beam, and a is the peak acceleration of the containment impact position along the impact direction.

[0167] S314, if the deformation of the bridge frame main beam along the bridge frame main beam direction meets the preset second type acceptance condition, the first dynamic response analysis result is that the bridge frame main beam will not be unstable as a whole and thus cause a falling accident.

[0168] S315, if the deformation of the bridge frame main beam along the bridge frame main beam direction does not meet the preset second type acceptance condition, the result corresponding to the first dynamic response analysis is that the bridge frame main beam will become unstable as a whole and cause a falling accident.

[0169] like Fig.15 As shown, the second dynamic response analysis of the ring crane includes the following steps:

[0170] S320, obtaining, from the numerical simulation calculation results, a second displacement time history curve of the ring beam when an external impactor impacts the bridge frame main beam in a direction perpendicular to the bridge frame main beam.

[0171] like Fig.16 This is a schematic diagram of an external impactor impacting the bridge in a direction perpendicular to the main beam.

[0172] S321, obtaining a maximum displacement of the ring beam along an impact direction parallel to the external impactor according to a second displacement time history curve of the ring beam.

[0173] S322, determining whether the maximum displacement of the ring beam along the impact direction parallel to the external impact object meets the preset third category acceptance condition.

[0174] The preset third type of acceptance conditions are: Where x is the maximum displacement of the ring beam parallel to the impact direction of the external impactor, H is the distance between the main beams of the bridge, and a x is the peak acceleration of the ring beam along the impact direction, and g is the gravitational acceleration.

[0175] S323, if the maximum displacement of the ring beam along the impact direction parallel to the external impact object meets the preset third-category acceptance condition, the second dynamic response analysis result is that the bridge main beam will not overturn and cause a falling accident.

[0176] S324, if the maximum displacement of the ring beam along the impact direction parallel to the external impact object does not meet the preset third-category acceptance condition, the second dynamic response analysis result is that the bridge main beam will overturn and cause a fall accident.

[0177] The corresponding analysis results are obtained based on the above-mentioned processes of the first dynamic response analysis and the second dynamic response analysis. If the result of the first dynamic response analysis is that the main beam of the bridge frame will not lose stability as a whole and cause a falling accident, and the result of the second dynamic response analysis is that the main beam of the bridge frame will not overturn and cause a falling accident, then the dynamic response analysis result is that the ring crane will not fall in the event of an external impact.

[0178] To achieve the above-mentioned purpose, the present invention proposes a safety assessment device for a ring crane in a nuclear island plant.

[0179] like Fig.17 1 shows a schematic diagram of a safety assessment device for a ring hoist in a nuclear island plant, comprising: an acquisition module 171, a first analysis module 172 and a second analysis module 173. The functions of each module will be described in detail below.

[0180] The acquisition module 171 is used to acquire the structural form of the containment in the nuclear island plant, which includes a double-layer containment and a single-layer containment.

[0181] The first analysis module 172 is used to perform a first vibration safety analysis on the ring hoist in the nuclear island building when an external impact occurs, if the containment shell is a double-layer containment shell, and determine the safety of the ring hoist according to the first vibration safety analysis result.

[0182] Furthermore, the first analysis module 172 is used to:

[0183] The process of the containment being subjected to external impact is numerically simulated.

[0184] The impact acceleration time history curve at the wheel is obtained from the numerical simulation calculation results, and the impact acceleration time history curve is converted into an impact acceleration spectrum.

[0185] Determine whether the preset seismic response spectrum can envelop the impact acceleration spectrum.

[0186] If the preset seismic response spectrum can envelop the impact acceleration spectrum, it is determined that the ring hanger is safe when an external impact occurs.

[0187] If the preset seismic response spectrum cannot envelop the impact acceleration spectrum, a spectrum analysis is performed on the ring hanger according to the impact acceleration spectrum, and the safety of the ring hanger in the event of an external impact is determined based on the spectrum analysis results.

[0188] Furthermore, the safety of the ring crane in the event of an external impact is determined based on the spectrum analysis results, including:

[0189] If the spectrum analysis result of the ring hanger is that the stress levels of the ring hanger components are all in the plastic stage, then a time history analysis of the ring hanger is performed according to the acceleration time history curve at the wheel.

[0190] Determine whether the time history analysis results meet the preset first-class acceptance conditions.

[0191] If the time history analysis results meet the preset first-category acceptance conditions, it is determined that the ring crane is safe in the event of an external impact.

[0192] If the time history analysis results do not meet the preset first-category acceptance conditions, it is determined that the ring crane will fall when an external impact occurs.

[0193] Further, a spectrum analysis is performed on the ring crane according to the impact acceleration spectrum, and the safety of the ring crane when an external impact occurs is determined based on the spectrum analysis result, which also includes:

[0194] If the result of spectrum analysis on the ring hanger is that the stress levels of the ring hanger components are all in the elastic deformation stage, it is determined that the ring hanger is safe in the event of an external impact.

[0195] Furthermore, the time history analysis results include the deformation of the bridge main beam along the bridge main beam direction, the maximum deflection of the bridge main beam, the displacement time history curve at the bridge main beam, the displacement time history curve at the end beam, and the displacement time history curve at the maintenance frame. The preset first-class acceptance conditions include:

[0196] The deformation ΔL of the bridge girder along the bridge girder direction satisfies ΔL≤L / 100, where L is the length of the bridge girder.

[0197] And the maximum deflection h of the bridge girder satisfies h≤L / 200, where L is the length of the bridge girder.

[0198] The displacement change in the displacement time history curve at the main beam of the bridge is within the range of ±0.05L, and the displacement change in the displacement time history curve at the end beam is within the range of ±0.05L. 端 Within the range, the displacement change in the displacement time history curve at the maintenance frame is within ±0.05L 检 In the range, L 端 is the length of the end beam, L 检 is the length of the maintenance rack.

[0199] The second analysis module 173 is used to perform a second vibration safety analysis and a dynamic response analysis on the ring crane if the containment shell is a single-layer containment shell, and determine the safety of the ring crane according to the second vibration safety analysis results and the dynamic response analysis results.

[0200] Furthermore, a second vibration safety analysis is performed on the ring crane, including:

[0201] The process of the containment being subjected to external impact is numerically simulated.

[0202] Obtaining the impact acceleration time history curve and the impact displacement time history curve at the wheel from the numerical simulation calculation results, and converting the impact acceleration time history curve and the impact displacement time history curve into an impact acceleration spectrum and an impact displacement spectrum respectively;

[0203] Determine the cutoff frequency corresponding to the maximum displacement in the impact displacement time history curve in the impact displacement spectrum;

[0204] The acceleration spectrum greater than the cut-off frequency is intercepted, and the intercepted acceleration spectrum is used to perform a second vibration safety analysis on the ring crane.

[0205] Furthermore, the dynamic response analysis includes a first dynamic response analysis and a second dynamic response analysis. The first dynamic response analysis of the ring crane includes:

[0206] The process of the containment being subjected to external impact is numerically simulated.

[0207] The first displacement time history curve of the ring beam when an external impactor hits the bridge main beam in a direction parallel to the bridge main beam is obtained from the numerical simulation calculation results.

[0208] The deformation of the bridge main beam along the bridge main beam direction is determined according to the first displacement time history curve of the ring beam.

[0209] Determine whether the deformation ΔL of the bridge frame main beam along the bridge frame main beam direction meets the preset second type acceptance conditions Wherein, L is the length of the bridge main beam, and a is the peak acceleration of the containment impact position along the impact direction.

[0210] If the deformation of the bridge frame main beam along the bridge frame main beam direction meets the preset second-category acceptance condition, the first dynamic response analysis result is that the bridge frame main beam will not become unstable as a whole and thus cause a falling accident.

[0211] If the deformation of the bridge frame main beam along the bridge frame main beam direction does not meet the preset second type of acceptance conditions, the result corresponding to the first dynamic response analysis is that the bridge frame main beam will become unstable as a whole and cause a falling accident.

[0212] Further, the deformation amount of the bridge frame main beam along the bridge frame main beam direction is determined according to the first displacement time history curve of the ring beam, including:

[0213] The maximum displacement of the ring beam at the impact position of the external impactor and the distance between the horizontal wheel and the ring beam are obtained from the first displacement time history curve of the ring beam.

[0214] According to the maximum displacement of the impact position of the external impactor and the distance between the horizontal wheel and the ring beam, the deformation of the bridge frame main beam along the bridge frame main beam direction is determined by Formula 1. Formula 1, ΔL=d-Δd, where d is the maximum displacement of the impact position of the external impactor, and Δd is the distance between the horizontal wheel and the ring beam.

[0215] Furthermore, the second dynamic response analysis of the ring crane is carried out, including:

[0216] The second displacement time history curve of the ring beam when an external impactor hits the bridge main beam in a direction perpendicular to the bridge main beam is obtained from the numerical simulation calculation results.

[0217] According to the second displacement time history curve of the ring beam, the maximum displacement of the ring beam along the impact direction parallel to the external impactor is obtained.

[0218] Determine whether the maximum displacement of the ring beam parallel to the impact direction of the external impactor meets the preset third-category acceptance conditions Where x is the maximum displacement of the ring beam parallel to the impact direction of the external impactor, H is the distance between the main beams of the bridge, and a x is the peak acceleration of the ring beam along the impact direction, and g is the gravitational acceleration.

[0219] If the maximum displacement of the ring beam along the impact direction parallel to the external impactor meets the preset third-category acceptance condition, the second dynamic response analysis result is that the main beam of the bridge will not overturn and cause a fall accident.

[0220] If the maximum displacement of the ring beam along the impact direction parallel to the external impactor does not meet the preset third-category acceptance condition, the second dynamic response analysis result will be that the main beam of the bridge will overturn and cause a fall accident.

[0221] Further, including:

[0222] If the first dynamic response analysis result is that the main beam of the bridge frame will not lose stability as a whole and cause a falling accident, and the second dynamic response analysis result is that the main beam of the bridge frame will not overturn and cause a falling accident, then the dynamic response analysis result is that the ring crane will not fall in the event of an external impact.

[0223] Further, the safety of the ring crane is determined according to the second vibration safety analysis result and the dynamic response analysis result, including:

[0224] If the second vibration safety analysis result and the dynamic response analysis result both indicate that the ring crane will not fall, it is determined that the ring crane is safe in the event of an external impact.

[0225] It should be understood that a safety assessment device for a ring hoist in a nuclear island building is consistent with the corresponding description of a safety assessment method for a ring hoist in a nuclear island building, so this embodiment will not be repeated.

[0226] In summary, it can be seen from the above description that the above embodiments of the present invention achieve the following technical effects:

[0227] 1. The present invention is based on the containment structure of the reactor building of a nuclear power plant and the transmission path of the impact when the containment is subjected to an external impact. Differentiated evaluation strategies are adopted for single-layer containment and double-layer containment. For the case where the reactor building has a double-layer containment, a vibration safety analysis of the ring hanger is carried out; for the case of a single-layer containment, a dynamic response analysis and a vibration safety analysis are carried out on the ring hanger respectively. The present invention provides a safety analysis process of the ring hanger under external impact to standardize the complex analysis process.

[0228] 2. When the present invention performs dynamic response analysis on the ring crane, the displacement time-history curves of the ring beam under different impact directions are extracted respectively according to the different external impact directions. The safety of the ring crane is comprehensively judged by judging whether the deformation of the bridge frame main beam along the main beam direction and the maximum displacement of the ring beam parallel to the impact direction meet multiple preset acceptance conditions. This method decouples the coupling problem and can ensure the accuracy of the analysis while improving the efficiency of the ring crane safety assessment.

[0229] 3. When analyzing the safety of the ring hanger in the single-layer containment, the present invention considers the dynamic response characteristics of the ring hanger during the impact process, and proposes to use the frequency corresponding to the macroscopic maximum displacement of the containment as the cutoff frequency to disassemble the acceleration spectrum, and then conduct vibration safety analysis and dynamic response analysis of the ring hanger respectively. This method and device can reduce the uncertainty and complexity in the analysis process, and designers can more intuitively understand the state of the ring hanger under external impact, thereby improving the accuracy and efficiency of the analysis.

[0230] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

[0231] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the existence of other identical elements in the process, method, article or device including the elements.

[0232] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as an ordered list of executable instructions for implementing logical functions, which can be embodied in any computer-readable medium for use by an instruction execution system, apparatus or device (such as a computer-based system, a system including a processor or other system that can fetch instructions from an instruction execution system, apparatus or device and execute instructions), or used in combination with these instruction execution systems, apparatuses or devices.

[0233] It should be understood that the various parts of the present invention can be implemented by hardware, software, firmware or a combination thereof. In the above-mentioned embodiments, a plurality of steps or methods can be implemented by software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented by hardware, as in another embodiment, it can be implemented by any one of the following technologies known in the art or their combination: a discrete logic circuit having a logic gate circuit for implementing a logic function for a data signal, a dedicated integrated circuit having a suitable combination of logic gate circuits, a programmable gate array (PGA), a field programmable gate array (FPGA), etc.

[0234] It should be noted that, in the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, unless they are contradictory.

Claims

1. A safety assessment method for a ring crane in a nuclear island plant, characterized in that: include: Obtaining the structural form of the containment in the nuclear island plant, wherein the structural form includes a double-layer containment and a single-layer containment; When an external impact occurs, if the containment shell is a double-layer containment shell, a first vibration safety analysis is performed on the ring hoist in the nuclear island plant, and the safety of the ring hoist is determined according to the result of the first vibration safety analysis; If the containment shell is a single-layer containment shell, a second vibration safety analysis and a dynamic response analysis are performed on the ring crane, and the safety of the ring crane is determined according to the second vibration safety analysis results and the dynamic response analysis results.

2. The method according to claim 1, characterized in that Performing a first vibration safety analysis on the ring hoist in the nuclear island plant, and determining the safety of the ring hoist according to the first vibration safety analysis result, including: Performing numerical simulation calculation on the process of the containment shell being subjected to external impact; Obtaining an impact acceleration time history curve at the wheel from the numerical simulation calculation results, and converting the impact acceleration time history curve into an impact acceleration spectrum; Determining whether a preset seismic response spectrum can envelop the impact acceleration spectrum; If the preset seismic response spectrum can envelop the impact acceleration spectrum, it is determined that the ring hanger is safe when an external impact occurs; If the preset seismic response spectrum cannot envelop the impact acceleration spectrum, a spectrum analysis is performed on the ring hanger according to the impact acceleration spectrum, and the safety of the ring hanger when an external impact occurs is determined based on the spectrum analysis result.

3. The method according to claim 2, characterized in that Determining the safety of the ring crane in the event of an external impact based on the spectrum analysis results includes: If the spectrum analysis result obtained by performing spectrum analysis on the ring hanger is that the stress levels of the ring hanger components are all in the plastic stage, then performing time history analysis on the ring hanger according to the acceleration time history curve at the wheel; Determine whether the time history analysis results meet the preset first-category acceptance conditions; If the time history analysis result meets the preset first type acceptance condition, it is determined that the ring crane is safe when an external impact occurs; If the time history analysis result does not meet the preset first type acceptance condition, it is determined that the ring crane will fall when an external impact occurs.

4. The method according to claim 3, characterized in that: Determining the safety of the ring crane in the event of an external impact based on the spectrum analysis result also includes: If the spectrum analysis performed on the ring hanger shows that the stress levels of the ring hanger components are all in the elastic deformation stage, it is determined that the ring hanger is safe when an external impact occurs.

5. The method according to claim 3, characterized in that: The time history analysis results include the deformation of the bridge frame main beam along the bridge frame main beam direction, the maximum deflection of the bridge frame main beam, the displacement time history curve at the bridge frame main beam, the displacement time history curve at the end beam, and the displacement time history curve at the maintenance frame. The preset first type of acceptance conditions include: The deformation amount ΔL of the bridge main beam along the bridge main beam direction satisfies ΔL≤L / 100, where L is the length of the bridge main beam, The maximum deflection h of the bridge girder satisfies h≤L / 200, where L is the length of the bridge girder. The displacement change in the displacement time history curve at the main beam of the bridge is within the range of ±0.05L, and the displacement change in the displacement time history curve at the end beam is within the range of ±0.05L. 端 Within the range, the displacement change in the displacement time history curve at the maintenance frame is within ±0.05L 检 In the range, L 端 is the length of the end beam, L 检 is the length of the maintenance rack.

6. The method according to claim 1, characterized in that A second vibration safety analysis is performed on the ring crane, including: Performing numerical simulation calculation on the process of the containment shell being subjected to external impact; Obtaining an impact acceleration time history curve and an impact displacement time history curve at the wheel from the numerical simulation calculation results, and converting the impact acceleration time history curve and the impact displacement time history curve into an impact acceleration spectrum and an impact displacement spectrum respectively; Determine a cutoff frequency corresponding to the maximum displacement in the impact displacement time history curve in the impact displacement spectrum; An impact acceleration spectrum greater than the cutoff frequency is intercepted, and the second vibration safety analysis is performed on the ring crane using the intercepted impact acceleration spectrum.

7. The method according to claim 1, characterized in that The dynamic response analysis includes a first dynamic response analysis and a second dynamic response analysis. The first dynamic response analysis is performed on the ring crane, including: Performing numerical simulation calculation on the process of the containment shell being subjected to external impact; The first displacement time history curve of the ring beam when the external impact object hits the bridge main beam in a direction parallel to the bridge main beam is obtained from the numerical simulation calculation results; Determining the deformation amount of the bridge frame main beam along the bridge frame main beam direction according to the first displacement time history curve of the ring beam; Determine whether the deformation ΔL of the bridge frame main beam along the bridge frame main beam direction meets the preset second type acceptance condition Wherein, L is the length of the bridge main beam, a is the peak acceleration of the impact position of the containment along the impact direction; If the deformation of the bridge frame main beam along the bridge frame main beam direction meets the preset second type of acceptance condition, the first dynamic response analysis result is that the bridge frame main beam will not become unstable as a whole and thus cause a falling accident; If the deformation of the bridge frame main beam along the bridge frame main beam direction does not meet the preset second type acceptance condition, the result corresponding to the first dynamic response analysis is that the bridge frame main beam will become unstable as a whole and cause a falling accident.

8. The method according to claim 7, characterized in that Determining the deformation amount of the bridge frame main beam along the bridge frame main beam direction according to the first displacement time history curve of the ring beam includes: Obtaining the maximum displacement of the ring beam at the impact position of the external impactor and the distance between the horizontal wheel and the ring beam from the first displacement time history curve of the ring beam; According to the maximum displacement of the impact position of the external impactor and the distance between the horizontal wheel and the ring beam, the deformation of the bridge frame main beam along the bridge frame main beam direction is determined by formula 1. In the formula 1, ΔL=d-Δd, wherein d is the maximum displacement of the impact position of the external impactor, and Δd is the distance between the horizontal wheel and the ring beam.

9. The method according to claim 7, characterized in that: Performing a second dynamic response analysis on the ring crane includes: Obtaining, from the numerical simulation calculation results, a second displacement time history curve of the ring beam when the external impactor impacts in a direction perpendicular to the bridge main beam; According to the second displacement time history curve of the ring beam, obtaining the maximum displacement of the ring beam along the impact direction parallel to the external impactor; Determine whether the maximum displacement of the ring beam along the impact direction parallel to the external impact object meets the preset third type acceptance condition Where x is the maximum displacement of the ring beam parallel to the impact direction of the external impactor, H is the distance between the main beams of the bridge, and a x is the peak acceleration of the ring beam along the impact direction, g is the gravitational acceleration; If the maximum displacement of the ring beam along the impact direction parallel to the external impact object meets the preset third type acceptance condition, the second dynamic response analysis result is that the bridge main beam will not overturn and thus cause a falling accident; If the maximum displacement of the ring beam along the impact direction parallel to the external impactor does not meet the preset third category acceptance condition, the second dynamic response analysis result is that the bridge main beam will overturn and cause a falling accident.

10. The method according to claim 7, characterized in that include: If the first dynamic response analysis result is that the bridge frame main beam will not lose stability as a whole and cause a falling accident, and the second dynamic response analysis result is that the bridge frame main beam will not overturn and cause a falling accident, then the dynamic response analysis result is that the ring crane will not fall when an external impact occurs.

11. The method according to any one of claims 1 to 10, characterized in that: Determining the safety of the ring crane according to the second vibration safety analysis result and the dynamic response analysis result includes: If both the second vibration safety analysis result and the dynamic response analysis result indicate that the ring hanger will not fall, it is determined that the ring hanger is safe when an external impact occurs.

12. A safety assessment device for a ring crane in a nuclear island plant, characterized in that: include: An acquisition module is used to acquire the structural form of the containment in the nuclear island plant, wherein the structural form includes a double-layer containment and a single-layer containment; A first analysis module is used for, when an external impact occurs, if the containment shell is a double-layer containment shell, performing a first vibration safety analysis on the ring hoist in the nuclear island plant, and determining the safety of the ring hoist according to the first vibration safety analysis result; The second analysis module is used to perform a second vibration safety analysis and a dynamic response analysis on the ring crane if the containment shell is a single-layer containment shell, and determine the safety of the ring crane according to the second vibration safety analysis results and the dynamic response analysis results.

13. The device according to claim 12, characterized in that The first analysis module is used to: Performing numerical simulation calculation on the process of the containment shell being subjected to external impact; Obtaining an impact acceleration time history curve at the wheel from the numerical simulation calculation results, and converting the impact acceleration time history curve into an impact acceleration spectrum; Determining whether a preset seismic response spectrum can envelop the impact acceleration spectrum; If the preset seismic response spectrum can envelop the impact acceleration spectrum, it is determined that the ring hanger is safe when an external impact occurs; If the preset seismic response spectrum cannot envelop the impact acceleration spectrum, a spectrum analysis is performed on the ring hanger according to the impact acceleration spectrum, and the safety of the ring hanger when an external impact occurs is determined based on the spectrum analysis result.

14. The device according to claim 13, characterized in that Determining the safety of the ring crane in the event of an external impact based on the spectrum analysis results includes: If the spectrum analysis result obtained by performing spectrum analysis on the ring hanger is that the stress levels of the ring hanger components are all in the plastic stage, then performing time history analysis on the ring hanger according to the acceleration time history curve at the wheel; Determine whether the time history analysis results meet the preset first-category acceptance conditions; If the time history analysis result meets the preset first type acceptance condition, it is determined that the ring crane is safe when an external impact occurs; If the time history analysis result does not meet the preset first type acceptance condition, it is determined that the ring crane will fall when an external impact occurs.

15. The device according to claim 14, characterized in that Performing spectrum analysis on the ring hanger according to the impact acceleration spectrum, and determining the safety of the ring hanger when an external impact occurs based on the spectrum analysis result, further comprising: If the spectrum analysis performed on the ring hanger shows that the stress levels of the ring hanger components are all in the elastic deformation stage, it is determined that the ring hanger is safe when an external impact occurs.

16. The device according to claim 14, characterized in that The time history analysis results include the deformation of the bridge frame main beam along the bridge frame main beam direction, the maximum deflection of the bridge frame main beam, the displacement time history curve at the bridge frame main beam, the displacement time history curve at the end beam, and the displacement time history curve at the maintenance frame. The preset first type of acceptance conditions include: The deformation amount ΔL of the bridge main beam along the bridge main beam direction satisfies ΔL≤L / 100, where L is the length of the bridge main beam, The maximum deflection h of the bridge girder satisfies h≤L / 200, where L is the length of the bridge girder. The displacement change in the displacement time history curve at the main beam of the bridge is within the range of ±0.05L, and the displacement change in the displacement time history curve at the end beam is within the range of ±0.05L. 端 Within the range, the displacement change in the displacement time history curve at the maintenance frame is within ±0.05L 检 In the range, L 端 is the length of the end beam, L 检 is the length of the maintenance rack.

17. The device according to claim 12, characterized in that A second vibration safety analysis is performed on the ring crane, including: Performing numerical simulation calculation on the process of the containment shell being subjected to external impact; Obtaining an impact acceleration time history curve and an impact displacement time history curve at the wheel from the numerical simulation calculation results, and converting the impact acceleration time history curve and the impact displacement time history curve into an impact acceleration spectrum and an impact displacement spectrum respectively; Determine a cutoff frequency corresponding to the maximum displacement in the impact displacement time history curve in the impact displacement spectrum; The acceleration spectrum greater than the cut-off frequency is intercepted, and the second vibration safety analysis is performed on the ring crane using the intercepted acceleration spectrum.

18. The device according to claim 12, characterized in that The dynamic response analysis includes a first dynamic response analysis and a second dynamic response analysis. The first dynamic response analysis is performed on the ring crane, including: Performing numerical simulation calculation on the process of the containment shell being subjected to external impact; The first displacement time history curve of the ring beam when the external impact object hits the bridge main beam in a direction parallel to the bridge main beam is obtained from the numerical simulation calculation results; Determining the deformation amount of the bridge frame main beam along the bridge frame main beam direction according to the first displacement time history curve of the ring beam; Determine whether the deformation ΔL of the bridge frame main beam along the bridge frame main beam direction meets the preset second type acceptance condition Wherein, L is the length of the bridge main beam, a is the peak acceleration of the impact position of the containment along the impact direction; If the deformation of the bridge frame main beam along the bridge frame main beam direction meets the preset second type of acceptance condition, the first dynamic response analysis result is that the bridge frame main beam will not become unstable as a whole and thus cause a falling accident; If the deformation of the bridge frame main beam along the bridge frame main beam direction does not meet the preset second type acceptance condition, the result corresponding to the first dynamic response analysis is that the bridge frame main beam will become unstable as a whole and cause a falling accident.

19. The device according to claim 18, characterized in that Determining the deformation amount of the bridge frame main beam along the bridge frame main beam direction according to the first displacement time history curve of the ring beam includes: Obtaining the maximum displacement of the ring beam at the impact position of the external impactor and the distance between the horizontal wheel and the ring beam from the first displacement time history curve of the ring beam; According to the maximum displacement of the impact position of the external impactor and the distance between the horizontal wheel and the ring beam, the deformation of the bridge frame main beam along the bridge frame main beam direction is determined by formula 1. In the formula 1, ΔL=d-Δd, wherein d is the maximum displacement of the impact position of the external impactor, and Δd is the distance between the horizontal wheel and the ring beam.

20. The device according to claim 18, characterized in that Performing a second dynamic response analysis on the ring crane includes: Obtaining, from the numerical simulation calculation results, a second displacement time history curve of the ring beam when the external impactor impacts in a direction perpendicular to the bridge main beam; According to the second displacement time history curve of the ring beam, obtaining the maximum displacement of the ring beam along the impact direction parallel to the external impactor; Determine whether the maximum displacement of the ring beam along the impact direction parallel to the external impact object meets the preset third type acceptance condition Where x is the maximum displacement of the ring beam parallel to the impact direction of the external impactor, H is the distance between the main beams of the bridge, and a x is the peak acceleration of the ring beam along the impact direction, g is the gravitational acceleration; If the maximum displacement of the ring beam along the impact direction parallel to the external impact object meets the preset third type acceptance condition, the second dynamic response analysis result is that the bridge main beam will not overturn and thus cause a falling accident; If the maximum displacement of the ring beam along the impact direction parallel to the external impactor does not meet the preset third category acceptance condition, the second dynamic response analysis result is that the bridge main beam will overturn and cause a falling accident.

21. The device according to claim 18, characterized in that include: If the first dynamic response analysis result is that the bridge frame main beam will not lose stability as a whole and cause a falling accident, and the second dynamic response analysis result is that the bridge frame main beam will not overturn and cause a falling accident, then the dynamic response analysis result is that the ring crane will not fall when an external impact occurs.

22. The device according to any one of claims 12 to 21, characterized in that Determining the safety of the ring crane according to the second vibration safety analysis result and the dynamic response analysis result includes: If both the second vibration safety analysis result and the dynamic response analysis result indicate that the ring hanger will not fall, it is determined that the ring hanger is safe when an external impact occurs.

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