Method and system for predicting service life of closed multi-cell steel structure

Abstract

The invention provides a life prediction method and system for a closed multi-cell steel structure, and relates to the technical field of structural finite element analysis, and the method comprises the steps: taking the closed multi-cell steel structure as a prototype, determining a scale reduction proportion, and building a scale reduction structure of the closed multi-cell steel structure; performing a laboratory accelerated environment test and a mechanical test on the scale structure in an equivalent service environment of the closed multi-cell steel structure, obtaining mechanical response test data of the scale structure, and determining test targets of the scale structure at different moments; establishing a scaling structure simulation model by taking the scaled plate material data as input, and obtaining a transfer coefficient; the method comprises the following steps of: establishing a full-scale structure simulation model of a closed multi-cell steel structure by taking original plate material data as input; and the full-scale structure simulation model is used for outputting the crack propagation size and the remaining life of the target welding structure at different moments under the full-scale structure. According to the method, the accuracy of life prediction of the closed multi-cell steel structure is effectively improved.

Description

Technical Field

[0001] The present invention relates to the technical field of structural finite element analysis, and in particular to a life prediction method and system for a closed multi-cell steel structure. Background Art

[0002] Large-scale enclosed multi-cell steel structures have the advantages of strong bearing capacity and fast construction speed. They are increasingly widely used in the fields of construction, bridges, wind power and aerospace support systems. Welding is the most important connection method for steel structures. Large-scale enclosed multi-cell steel structures have a large number of welds and most of them are hidden, making it difficult to detect cracks, making it impossible to detect cracks in time, thus posing a huge safety hazard.

[0003] Closed multi-cell steel structures are usually used in ships, underwater structures, bridges, storage tanks or offshore platforms. Due to the harsh environment, the corrosion damage of the structure is accelerated and the fatigue life is significantly reduced. Life prediction is a key factor in ensuring its long-term reliability, safety and functionality. The life prediction method of large-scale closed multi-cell steel structures can better extend the service life of the structure, improve economic benefits and safety, and ultimately enhance the reliability and performance of the steel structure.

[0004] However, the test sites and equipment of traditional life prediction methods usually cannot provide sufficient loading capacity to simulate actual working conditions. Loads that match actual conditions cannot be applied during the test, which limits the accurate measurement of the mechanical response of the structure under actual service conditions. For full-scale experiments on large steel structures, the test equipment and sites are extremely demanding, resulting in huge costs and difficulty in conducting large-scale fatigue tests and repeatable tests. Existing simulation methods are prone to deviations when accurately simulating crack propagation, resulting in low efficiency in life prediction and inability to guarantee accuracy. Summary of the invention

[0005] In order to solve the technical problems that the test sites and equipment of traditional life prediction methods in the prior art are usually unable to provide sufficient loading capacity to simulate actual working conditions, and loads consistent with actual conditions cannot be applied during the test, which limits the accurate measurement of the mechanical response of the structure under the actual service environment, and for full-scale experiments on large steel structures, the test equipment and sites have extremely high requirements, resulting in huge costs and difficulty in conducting large-scale fatigue tests and repeatability tests, and the existing simulation methods are prone to deviations when accurately simulating crack propagation, resulting in low efficiency of life prediction and inability to ensure accuracy, the present invention provides a life prediction method and system for a closed multi-cell steel structure.

[0006] The technical solution provided by the embodiment of the present invention is as follows:

[0007] First aspect

[0008] An embodiment of the present invention provides a life prediction method for a closed multi-cell steel structure, comprising:

[0009] S1: Taking the enclosed multi-cell steel structure as the prototype, the scaling ratio of the enclosed multi-cell steel structure is determined based on the stiffness equivalence principle;

[0010] S2: using the scaled plate to establish a scaled structure of the closed multi-cell steel structure according to the scaled ratio, wherein the scaled plate is a thin plate material obtained by scaling the original plate of the closed multi-cell steel structure according to the scaled ratio;

[0011] S3: Conduct physical tests on scaled plates and scaled structures in an equivalent service environment of a closed multi-cell steel structure, obtain mechanical response test data of the scaled structure under a preset load, and determine the test targets of the scaled structure at different times, where the test targets include the crack extension size of the target welded structure and the remaining life of the target welded structure;

[0012] S4: Using the scaled plate material data as input data, a scaled structure simulation model of the scaled structure is established with the goal of achieving the mechanical response test data, and the transfer coefficients between the closed multi-cell steel structure material parameters and each test target in the scaled structure simulation model are obtained, wherein the transfer relationship includes the crack growth coefficient and the remaining life variation coefficient;

[0013] S5: Using the original plate material data as input data, a full-scale structural simulation model of the closed multi-cell steel structure is established according to the transfer coefficient;

[0014] S6: Use the full-scale structure simulation model to output the crack extension size and remaining life of the target welded structure at different times under the full-scale structure.

[0015] Second aspect

[0016] An embodiment of the present invention provides a life prediction system for a closed multi-cell steel structure, comprising:

[0017] processor;

[0018] A memory having computer-readable instructions stored therein, which, when executed by a processor, implements the life prediction method for a closed multi-cell steel structure according to the first aspect.

[0019] The third aspect

[0020] An embodiment of the present invention provides a computer-readable storage medium, on which a computer program is stored. When the program is executed by a processor, the life prediction method of the closed multi-cell steel structure as described in the first aspect is implemented.

[0021] The beneficial effects brought about by the technical solution provided by the embodiment of the present invention include at least:

[0022] In the present invention, by establishing a scaled-down structure, the demand for test sites and equipment is effectively reduced, the experimental cost is reduced, and effective mechanical response tests can still be performed under limited loading capacity and test conditions, providing a realistic and feasible way for life prediction of large structures. The simulation results are verified and corrected by mechanical response test data, and crack propagation can be accurately simulated, which improves the accuracy of the simulation results. In physical experiments, the effects of static loads and fatigue loads are comprehensively considered to make the life prediction more in line with actual use conditions. According to the transfer coefficient between the material parameters of the closed multi-cell steel structure and each test target, the test results of the scaled-down model are effectively transferred to the full-scale structural model, avoiding prediction errors caused by differences in structural size or loading conditions, improving the accuracy and reliability of the prediction, and being able to better reflect the crack propagation size and remaining life of the closed multi-cell steel structure under actual service conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0024] Figure 1 A schematic flow chart of a life prediction method for a closed multi-cell steel structure provided by an embodiment of the present invention;

[0025] Figure 2 A schematic diagram of a closed multi-cell steel structure provided in an embodiment of the present invention;

[0026] Figure 3 A schematic structural diagram of a life prediction system for a closed multi-cell steel structure provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0027] The technical solution of the present invention is described below in conjunction with the accompanying drawings.

[0028] In the embodiments of the present invention, words such as "exemplarily" and "for example" are used to indicate examples, illustrations or explanations. Any embodiment or design described as "example" in the present invention should not be interpreted as being more preferred or more advantageous than other embodiments or designs. Specifically, the use of the word "example" is intended to present the concept in a specific way. In addition, in the embodiments of the present invention, the meaning expressed by "and / or" can be both, or it can be either of the two.

[0029] In order to make the technical problems, technical solutions and advantages to be solved by the present invention more clear, a detailed description will be given below with reference to the accompanying drawings and specific embodiments.

[0030] Reference Manual Attached Figure 1 , showing a flow chart of a life prediction method for a closed multi-cell steel structure provided in an embodiment of the present invention.

[0031] An embodiment of the present invention provides a life prediction method for a closed multi-cell steel structure, comprising:

[0032] S1: Taking the enclosed multi-cell steel structure as the prototype, the scaling ratio of the enclosed multi-cell steel structure is determined based on the stiffness equivalence principle.

[0033] Among them, the preset ratio refers to the reduction ratio determined according to the experimental conditions (such as site, equipment loading capacity, etc.), which is used to construct a reduced model corresponding to the actual size. The closed multi-cell steel structure refers to a steel load-bearing structure composed of multiple compartments or confined spaces. The scaled structure is a model reduced according to the preset ratio, and has geometric and mechanical properties similar to the actual structure.

[0034] It should be noted that those skilled in the art can set the size of the preset ratio according to actual needs, and the present invention is not limited thereto.

[0035] Specifically, evaluate the space size of the existing test site and the maximum loading capacity of the equipment to ensure that the scaled model can operate within the loading range of the equipment and meet the site conditions; select the corresponding scale ratio based on the similarity between the mechanical properties of the scaled structure and the full-scale structure to ensure the validity and representativeness of the experimental data; on this basis, through the trade-off between the test equipment capabilities, site conditions and cost budget, select the scale ratio (such as 1:10) that can achieve the test objectives from the above ratios.

[0036] In a possible implementation, the scaling ratio of the enclosed multi-cell steel structure to the scaled structure is specifically 10:1.

[0037] It should be noted that the scaling ratio determination based on the stiffness equivalence principle can optimize the design of the closed multi-cell steel structure, improve its mechanical properties and safety, and ensure the stability and reliability of the structure at different sizes.

[0038] S2: Using a scaled plate, a scaled structure of the closed multi-cell steel structure is established according to a scaled ratio, wherein the scaled plate is a thin plate material obtained by scaling an original plate of the closed multi-cell steel structure according to the scaled ratio.

[0039] In a possible implementation, the scaled plate closed multi-cell steel structure material includes a scaled closed multi-cell steel structure base material and a scaled closed multi-cell steel structure weld material.

[0040] Among them, the parent material of the closed multi-cell steel structure refers to the original material part of the steel structure that has not been welded, which is usually used to bear the main stress of the structure; the weld material of the closed multi-cell steel structure is the welding material used to connect different parent material parts, which usually has similar mechanical properties to the parent material, but needs to have good weldability and high fatigue resistance.

[0041] Specifically, by considering the parent material and weld material separately, the overall performance and local fatigue behavior of the structure can be evaluated more accurately, making the prediction of crack propagation and remaining life more accurate, which helps to improve the safety and service life of steel structures.

[0042] It should be noted that constructing a scaled-down structure can be tested under limited experimental sites and equipment loading capacity, reducing experimental costs while maintaining mechanical similarity to the full-scale structure, ensuring the validity and representativeness of the experimental data, verifying the design scheme in the early stage of the experiment, improving the accuracy of the simulation model, and reducing the risk and difficulty of full-scale experiments.

[0043] S3: Conduct physical tests on scaled plates and scaled structures in an equivalent service environment of a closed multi-cell steel structure, obtain the mechanical response test data of the scaled structure under a preset load, and determine the test targets of the scaled structure at different times, where the test targets include the crack extension size of the target welded structure and the remaining life of the target welded structure.

[0044] Among them, the service environment of the closed multi-cell steel structure refers to the environmental conditions in which the steel structure is actually used. In the present invention, it refers to the offshore environment, including factors such as temperature, humidity, corrosion and load. The preset load is a static or dynamic load artificially applied in the experiment to simulate the stress conditions in actual use. The crack extension size refers to the change of the size of the crack in the welded structure with time or load. The remaining life refers to the time or load cycle that the steel structure can still be safely used under the current conditions.

[0045] In one possible implementation, the physical test includes a tensile test, an extension test, and a fracture toughness test.

[0046] Among them, the tensile test is to apply tensile force to the specimen to measure its strength, elongation, breaking point and other characteristics during the stretching process. The extension test is used to evaluate the behavior of crack extension in the material, usually by observing the crack extension rate through cyclic loading. The fracture toughness test measures the material's ability to resist crack extension, reflecting the material's toughness and fracture resistance.

[0047] It should be noted that the combination of tensile tests, extension tests and fracture toughness tests can comprehensively evaluate the mechanical properties of steel structure materials under different load and stress states, provide more accurate material property data, help predict the crack propagation behavior and remaining life of materials in practical applications, and improve the scientificity and reliability of structural design and maintenance.

[0048] In a possible implementation manner, the preset load includes a static load and a fatigue load.

[0049] Among them, static load refers to the constant, time-invariant load acting on the structure, such as gravity or fixed pressure, and fatigue load refers to the load applied repeatedly or cyclically, which may induce fatigue damage to the material over time, leading to crack propagation or fracture.

[0050] It should be noted that static loads can help evaluate the bearing capacity of a structure under constant stress, while fatigue loads can simulate the effects of cyclic stress on materials and welds in actual working conditions. By considering these two types of loads at the same time, the strength, fatigue life and crack propagation behavior of steel structures can be predicted more comprehensively, thereby improving the accuracy of structural design and life prediction.

[0051] In a possible implementation, the structural test includes a static test and a prefabricated crack fatigue test.

[0052] Among them, the static test is to apply a constant static load to the structure to evaluate its deformation, stiffness and bearing capacity under fixed stress. The prefabricated crack fatigue test is to introduce cracks into the structure in advance and apply fatigue loads cyclically to observe the crack expansion behavior, thereby evaluating the fatigue performance and fracture risk of the material under long-term loading conditions.

[0053] Specifically, tensile tests were carried out on the scaled-down structure using thin plate base materials and weld materials. Since the cracks were all located in the weld area, metal fatigue crack propagation tests were mainly carried out on the weld materials. At the same time, static tests and fatigue tests on prefabricated cracks were carried out on the scaled-down structure. Among them, the static tests and fatigue tests on prefabricated cracks measured the mechanical response data of the scaled-down structure under static and fatigue loads by arranging force, displacement and strain sensors.

[0054] It should be noted that by conducting physical tests in a service environment and obtaining the true mechanical response data of the scaled structure, it is possible to more accurately simulate the actual use conditions, thereby dynamically monitoring and evaluating the crack propagation and remaining life of the welded structure, thereby improving the reliability of life prediction, helping to identify potential structural problems in advance, and ensuring structural safety.

[0055] S4: Using the scaled plate material data as input data, a scaled structure simulation model of the scaled structure is established with the goal of achieving the mechanical response test data, and the transfer coefficients between the closed multi-cell steel structure material parameters and each test target in the scaled structure simulation model are obtained, wherein the transfer relationship includes the crack propagation coefficient and the remaining life variation coefficient.

[0056] Among them, the scaled-down structure simulation model is a computer model constructed based on the scaled-down structure and test data, which is used to simulate the mechanical behavior of the real structure under different load conditions. The transfer coefficient is a coefficient that describes the relationship between the material parameters in the simulation model and the test targets (such as crack extension size and remaining life). The crack extension coefficient reflects the relationship between the crack extension rate and the load or stress. The remaining life variation coefficient is used to predict the change in the remaining life of the structure under different conditions.

[0057] In a possible implementation manner, the mechanical response test data includes mechanical response test data under static load and mechanical response test data under fatigue load.

[0058] It should be noted that by combining the mechanical response test data under static and fatigue loads, the performance of the structure under different load conditions can be comprehensively evaluated. The static load data can verify the bearing capacity of the structure, while the fatigue load data can predict the long-term durability and crack propagation of the structure, helping to optimize the structural design and improve the accuracy of life prediction.

[0059] In a possible implementation, the mechanical response under a static load includes an overall deformation of the scaled structure, an overall stiffness value of the scaled structure, and a local stress value of the scaled structure.

[0060] Among them, the overall deformation refers to the overall deformation degree of the scaled structure under the action of static load, which reflects the flexibility or rigidity of the structure. The overall stiffness value is a measure of the ability of the structure to resist deformation when subjected to force. The greater the stiffness, the less likely the structure is to deform. The local stress value refers to the stress borne by certain specific areas of the structure, which is usually used to analyze the stress concentration phenomenon of the structure.

[0061] It should be noted that by evaluating the overall deformation, stiffness and local stress values, the mechanical behavior of the scaled structure under static load can be fully understood, which helps to identify possible structural weaknesses, optimize the design, improve the bearing capacity and safety of the structure, and ensure the reliability and stability of the structure in practical applications.

[0062] In a possible implementation manner, the mechanical response under fatigue load includes the initiation time of the fatigue crack and the extension size of the fatigue crack.

[0063] Among them, the moment of fatigue crack generation refers to the specific point in time when cracks begin to appear in the material or structure under the action of fatigue load, which is an important indicator for evaluating the fatigue performance of the material. The expansion size of the fatigue crack refers to the size of the expansion of the crack that has already occurred under continuous fatigue load as the cyclic load is applied, which is crucial for evaluating the life and safety of the material.

[0064] In actual operation, initial defects are prefabricated in the welds at the bottom of the second and fourth supporting points, and the fatigue load is loaded in a step-by-step manner. The load levels are set to 1P, 2P and 3P respectively, and the generation of fatigue cracks during loading is monitored in real time. The test results show that when the fatigue peak loads are 1P and 2P, no fatigue cracks are generated in the defects; when the load reaches 3P, fatigue cracks begin to appear at the weld defects at the bottom of the second supporting point. These results are basically consistent with the experimental phenomena, verifying the accuracy of the scaled simulation model under fatigue conditions. On the whole, the test and simulation model complement each other and effectively evaluate the fatigue performance and crack propagation characteristics of the scaled structure.

[0065] It should be noted that by establishing a simulation model and obtaining the transfer coefficient, the mechanical behavior of the scaled structure under different load conditions can be simulated and predicted more efficiently and accurately. The introduction of the transfer coefficient enables the simulation results to more accurately reflect the dynamic changes of crack propagation and remaining life, which helps to improve the accuracy of structural life prediction and reduce test costs and time.

[0066] S5: Using the original plate material data as input data, a full-scale structural simulation model of the closed multi-cell steel structure is established based on the transfer coefficient.

[0067] It should be noted that by establishing a full-scale structural simulation model through the transfer coefficient, the mechanical behavior of the closed multi-cell steel structure under actual working conditions can be accurately simulated. The simulation model is expanded based on the test and calculation results of the scaled model, ensuring the accuracy of crack propagation and remaining life prediction.

[0068] S6: Use the full-scale structure simulation model to output the crack extension size and remaining life of the target welded structure at different times under the full-scale structure.

[0069] It should be noted that by using the full-scale structural simulation model to output the crack propagation size and remaining life of the welded structure, the fatigue behavior of the structure can be accurately predicted under full-scale conditions, avoiding the errors that may be caused by relying solely on the scaled model, and providing crack propagation and life assessment in a more realistic engineering scenario. This process is efficient and economical, and can provide an accurate basis for engineering decision-making without conducting full-scale physical tests, thereby improving the safety, reliability and maintenance efficiency of the structure and reducing operating costs and risks.

[0070] Reference Manual Attached Figure 2 , showing a schematic diagram of a closed multi-cell steel structure provided in an embodiment of the present invention.

[0071] like Figure 2 The closed multi-cell steel structure is a steel box girder composed of the first support point, the second support point, the third support point, the fourth support point, a bidirectional cross beam, a short beam and a rectangular outer edge. Among them, the 1#~4# area on the upper plate of the double cross beam bears the vertical concentrated force, and the bottom of the rectangular outer edge bears the vertical upward support force provided by the surrounding support surfaces. The bidirectional cross beam, short beam and rectangular outer edge in the core bearing area are all welded steel plates to form components, and the components are connected by bolts to form a complete structure. In addition, stiffening ribs with a certain spacing are arranged inside all components to form a multi-cell steel beam. In order to ensure the safety of the structure in service, it is necessary to examine the expansion and remaining life of the cracks in the weld at the tensile part at the bottom of the fourth support point under the service condition.

[0072] For example, taking a large steel box girder structure as the prototype, a scale ratio of 1:10 is selected to construct the scaled structure based on the loading capacity of the test site and equipment, and tensile tests are carried out on the thin plate base material and weld material of the scaled structure. Since the cracks are all arranged in the weld area, fatigue crack propagation tests are especially carried out on the weld material metal. The mechanical response of the scaled structure under static and fatigue loads is measured by force, displacement and strain sensors, and important data such as the overall deformation, stiffness and local stress of the scaled structure under static load and fatigue conditions are obtained. A scaled structure simulation model of the scaled structure is established, and static tests on the scaled structure and fatigue tests on prefabricated cracks are carried out to verify the accuracy of the scaled model in static analysis and fatigue analysis, and the transfer coefficients of the material parameters of the closed multi-cell steel structure and each test target are obtained. Based on the transfer coefficients, a full-scale simulation model is constructed, and the crack propagation size and remaining life of the crack in service are obtained through simulation analysis.

[0073] The beneficial effects brought about by the technical solution provided by the embodiment of the present invention include at least:

[0074] In the present invention, by establishing a scaled-down structure, the demand for test sites and equipment is effectively reduced, the experimental cost is reduced, and effective mechanical response tests can still be performed under limited loading capacity and test conditions, providing a realistic and feasible way for life prediction of large structures. The simulation results are verified and corrected by mechanical response test data, and crack propagation can be accurately simulated, which improves the accuracy of the simulation results. In physical experiments, the effects of static loads and fatigue loads are comprehensively considered to make the life prediction more in line with actual use conditions. According to the transfer coefficient between the material parameters of the closed multi-cell steel structure and each test target, the test results of the scaled-down model are effectively transferred to the full-scale structural model, avoiding prediction errors caused by differences in structural size or loading conditions, improving the accuracy and reliability of the prediction, and being able to better reflect the crack propagation size and remaining life of the closed multi-cell steel structure under actual service conditions.

[0075] Reference Manual Attached Figure 3 , showing a schematic structural diagram of a life prediction system for a closed multi-cell steel structure provided by the present invention.

[0076] The present invention further provides a life prediction system 20 for a closed multi-cell steel structure, which is applied to the life prediction method for the closed multi-cell steel structure, and comprises:

[0077] Processor 201.

[0078] The memory 202 stores computer-readable instructions. When the computer-readable instructions are executed by the processor 201, the life prediction method of the closed multi-cell steel structure in the method embodiment is implemented.

[0079] The life prediction system 20 for a closed multi-cell steel structure provided by the present invention can execute the above-mentioned life prediction method for a closed multi-cell steel structure and achieve the same or similar technical effects. To avoid repetition, the present invention will not elaborate on it.

[0080] The beneficial effects brought about by the technical solution provided by the embodiment of the present invention include at least:

[0081] In the present invention, by establishing a scaled-down structure, the demand for test sites and equipment is effectively reduced, the experimental cost is reduced, and effective mechanical response tests can still be performed under limited loading capacity and test conditions, providing a realistic and feasible way for life prediction of large structures. The simulation results are verified and corrected by mechanical response test data, and crack propagation can be accurately simulated, which improves the accuracy of the simulation results. In physical experiments, the effects of static loads and fatigue loads are comprehensively considered to make the life prediction more in line with actual use conditions. According to the transfer coefficient between the material parameters of the closed multi-cell steel structure and each test target, the test results of the scaled-down model are effectively transferred to the full-scale structural model, avoiding prediction errors caused by differences in structural size or loading conditions, improving the accuracy and reliability of the prediction, and being able to better reflect the crack propagation size and remaining life of the closed multi-cell steel structure under actual service conditions.

[0082] It should be understood that the processor in the embodiment of the present invention may be a central processing unit (CPU), and the processor may also be other general-purpose processors, digital signal processors (DSP), application specific integrated circuits (ASIC), field programmable gate arrays (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor may be a microprocessor or the processor may also be any conventional processor, etc.

[0083] It should also be understood that the memory in the embodiments of the present invention may be a volatile memory or a non-volatile memory, or may include both volatile and non-volatile memories. Among them, the non-volatile memory may be a read-only memory (ROM), a programmable read-only memory (PROM), an erasable programmable read-only memory (EPROM), an electrically erasable programmable read-only memory (EEPROM), or a flash memory. The volatile memory may be a random access memory (RAM), which is used as an external cache. By way of example and not limitation, many forms of random access memory (RAM) are available, such as static RAM (SRAM), dynamic random access memory (DRAM), synchronous DRAM (SDRAM), double data rate synchronous dynamic random access memory (DDR SDRAM), enhanced synchronous dynamic random access memory (ESDRAM), synchronous link DRAM (SLDRAM), and direct rambus RAM (DR RAM).

[0084] The above embodiments can be implemented in whole or in part by software, hardware (such as circuits), firmware or any other combination. When implemented by software, the above embodiments can be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions or computer programs. When a computer instruction or computer program is loaded or executed on a computer, a process or function according to an embodiment of the present invention is generated in whole or in part. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. Computer instructions can be stored in a computer-readable storage medium, or transmitted from one computer-readable storage medium to another computer-readable storage medium. For example, computer instructions can be transmitted from one website, computer, server or data center to another website, computer, server or data center by wired (such as infrared, wireless, microwave, etc.). The computer-readable storage medium can be any available medium that can be accessed by a computer or a data storage device such as a server or data center that contains one or more available media sets. The available medium can be a magnetic medium (for example, a floppy disk, a hard disk, a tape), an optical medium (for example, a DVD), or a semiconductor medium. The semiconductor medium can be a solid-state hard disk.

[0085] It should be understood that the term "and / or" in this article is only a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. A and B can be singular or plural. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship, but it may also indicate an "and / or" relationship. Please refer to the context for specific understanding.

[0086] In the present invention, "at least one" means one or more, and "plurality" means two or more. "At least one of the following" or similar expressions refers to any combination of these items, including any combination of single items or plural items. For example, at least one of a, b, or c can mean: a, b, c, ab, ac, bc, or abc, where a, b, and c can be single or multiple.

[0087] It should be understood that in various embodiments of the present invention, the size of the serial numbers of the above-mentioned processes does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present invention.

[0088] Those skilled in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of the present invention.

[0089] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working processes of the above-described equipment, devices and units can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0090] In the several embodiments provided by the present invention, it should be understood that the disclosed devices, apparatuses and methods can be implemented in other ways. For example, the device embodiments described above are only schematic, for example, the division of units is only a logical function division, and there may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another device, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0091] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0092] In addition, each functional unit in each embodiment of the present invention may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit.

[0093] If the function is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art, or the part of the technical solution, can be embodied in the form of a software product. The computer software product is stored in a storage medium, including several instructions for a computer device (which can be a personal computer, server, or network device, etc.) to perform all or part of the steps of the methods of various embodiments of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM), random access memory (RAM), disk or optical disk, etc., various media that can store program codes.

[0094] An embodiment of the present invention provides a computer-readable storage medium having a computer program stored thereon. When the program is executed by a processor, a life prediction method for a closed multi-cell steel structure is implemented as in the method embodiment.

[0095] A computer-readable storage medium provided by the present invention can implement the steps and effects of the life prediction method of a closed multi-cell steel structure of the above method embodiment. To avoid repetition, the present invention will not go into details.

[0096] The beneficial effects brought about by the technical solution provided by the embodiment of the present invention include at least:

[0097] In the present invention, by establishing a scaled-down structure, the demand for test sites and equipment is effectively reduced, the experimental cost is reduced, and effective mechanical response tests can still be performed under limited loading capacity and test conditions, providing a realistic and feasible way for life prediction of large structures. The simulation results are verified and corrected by mechanical response test data, and crack propagation can be accurately simulated, which improves the accuracy of the simulation results. In physical experiments, the effects of static loads and fatigue loads are comprehensively considered to make the life prediction more in line with actual use conditions. According to the transfer coefficient between the material parameters of the closed multi-cell steel structure and each test target, the test results of the scaled-down model are effectively transferred to the full-scale structural model, avoiding prediction errors caused by differences in structural size or loading conditions, improving the accuracy and reliability of the prediction, and being able to better reflect the crack propagation size and remaining life of the closed multi-cell steel structure under actual service conditions.

[0098] The above are only specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art who is familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed by the present invention, which should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

[0099] There are a few points to note:

[0100] (1) The drawings of the embodiments of the present invention only involve structures related to the embodiments of the present invention. Other structures may refer to conventional designs.

[0101] (2) For the sake of clarity, in the drawings used to describe the embodiments of the present invention, the thickness of layers or regions is exaggerated or reduced, that is, these drawings are not drawn according to the actual scale. It is understood that when an element such as a layer, film, region or substrate is referred to as being "on" or "under" another element, the element may be "directly" "on" or "under" the other element or there may be intermediate elements.

[0102] (3) In the absence of conflict, the embodiments of the present invention and the features therein may be combined with each other to obtain new embodiments.

[0103] The above are only specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto. The protection scope of the present invention shall be based on the protection scope of the claims.

Claims

1. A method for predicting the life of a closed multi-cell steel structure, characterized in that: include: S1: Taking the enclosed multi-cell steel structure as a prototype, the scaling ratio of the enclosed multi-cell steel structure is determined based on the stiffness equivalence principle; S2: using a scaled plate to establish a scaled structure of the enclosed multi-cell steel structure according to the scaled ratio, wherein the scaled plate is a thin plate material obtained by scaling an original plate of the enclosed multi-cell steel structure according to the scaled ratio; S3: Performing physical tests on the scaled plate and the scaled structure in an equivalent service environment of a closed multi-cell steel structure, obtaining mechanical response test data of the scaled structure under a preset load, and determining test targets of the scaled structure at different times, wherein the test targets include a crack extension size of a target welded structure and a remaining life of a target welded structure; S4: using the scaled plate material data as input data, establishing a scaled structure simulation model of the scaled structure with the goal of achieving the mechanical response test data, and obtaining the transfer coefficient between the closed multi-cell steel structure material parameters and each test target in the scaled structure simulation model, wherein the transfer relationship includes the crack growth coefficient and the remaining life variation coefficient; S5: using the original plate material data as input data and establishing a full-scale structural simulation model of the closed multi-cell steel structure according to the transfer coefficient; S6: using the full-scale structure simulation model to output the crack extension size and remaining life of the target welded structure at different times under the full-scale structure.

2. The life prediction method of a closed multi-cell steel structure according to claim 1, characterized in that: The scale ratio of the enclosed multi-cell steel structure to the scaled structure is specifically 10:

1.

3. The life prediction method of a closed multi-cell steel structure according to claim 1, characterized in that: The zoom plate includes a zoom structure base material and a zoom structure weld material.

4. The life prediction method of a closed multi-cell steel structure according to claim 1, characterized in that: The physical tests include tensile tests, extension tests and fracture toughness tests.

5. The life prediction method of a closed multi-cell steel structure according to claim 1, characterized in that: The preset load includes a static load and a fatigue load.

6. The life prediction method of a closed multi-cell steel structure according to claim 5, characterized in that: The mechanical response test data include mechanical response test data of the scaled structure under static load and mechanical response test data under fatigue load.

7. The life prediction method of a closed multi-cell steel structure according to claim 6, characterized in that: The mechanical response under the static load includes the overall deformation of the scaled structure, the overall stiffness value of the scaled structure and the local stress value of the scaled structure.

8. The life prediction method of a closed multi-cell steel structure according to claim 6, characterized in that: The mechanical response under the fatigue load includes the generation time of the fatigue crack and the extension size of the fatigue crack.

9. A life prediction system for a closed multi-cell steel structure, characterized in that: include: processor; A memory having computer-readable instructions stored thereon, wherein when the computer-readable instructions are executed by the processor, the life prediction method for a closed multi-cell steel structure according to any one of claims 1 to 8 is implemented.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the program is executed by a processor, the life prediction method of the closed multi-cell steel structure according to any one of claims 1 to 8 is implemented.

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