Method and system for determining ultimate bearing capacity of ocean jacket type platform

Abstract

The invention provides a method and system for determining ultimate bearing capacity of an ocean jacket type platform, and relates to the technical field of ocean engineering.The method comprises the specific steps that environmental parameters, structural parameters and load parameters of the platform are collected; based on dimensionless processing, generating a corresponding environmental influence index, a material influence index and a load index; carrying out fusion and correlation analysis on the three indexes to obtain a comprehensive bearing capacity evaluation index; and determining the ultimate bearing capacity of the ocean jacket type platform by combining the bearing capacity evaluation index and the safety coefficient of the material. According to the method, the environment influence index, the material influence index and the load index are fused through dimensionless processing and correlation analysis, the actual bearing capacity of the platform under the complex ocean condition can be reflected more accurately, and therefore the design risk is reduced. Besides, the final bearing capacity is determined by combining the safety coefficient of the material, so that the safety and reliability of the platform are improved, the maintenance cost is reduced, and the service life is prolonged.

Description

Technical Field

[0001] The present invention relates to the field of marine engineering technology, and in particular to a method and system for determining the ultimate bearing capacity of an offshore jacket platform. Background Art

[0002] In the process of marine resource development, the safety and bearing capacity assessment of offshore jacket platforms as key infrastructure is crucial. Existing bearing capacity assessment methods are mostly based on traditional design standards and empirical formulas, usually focusing on static loads and ignoring the complexity of dynamic environmental factors. This assessment method often fails to effectively consider the interaction of factors such as waves, wind speed, and currents in the marine environment, as well as the variability of these factors over time, resulting in insufficient prediction of potential extreme conditions during design. In addition, existing methods often use simplified material performance models that fail to fully reflect the true performance of materials under different environmental conditions, such as how the strength and toughness of materials change under extreme temperatures or highly corrosive environments, which may lead to sudden failure at critical moments.

[0003] In addition, many existing technologies lack a comprehensive analysis of load changes when conducting ultimate bearing capacity assessments, especially insufficient consideration of dynamic loads. Wave action, wind loads, and changes in current forces in the marine environment are important factors affecting platform safety, but the complexity and uncertainty of these dynamic factors are often simplified or ignored. This calls into question the reliability of the assessment results, resulting in the inability to accurately predict the actual bearing capacity and safety of the platform during the design phase. Therefore, a more systematic and comprehensive assessment method is urgently needed to overcome these technical deficiencies and ensure the safety and reliability of offshore jacket platforms in actual operations.

[0004] The above information disclosed in this Background section is only for enhancement of understanding of the background of the present disclosure and therefore it may contain information that does not constitute the prior art that is already known to one of ordinary skill in the art. Summary of the invention

[0005] The object of the present invention is to provide a method and system for determining the ultimate bearing capacity of an offshore jacket platform, so as to solve the problems raised in the above-mentioned background technology.

[0006] To achieve the above object, the present invention provides the following technical solutions:

[0007] A method for determining the ultimate bearing capacity of an offshore jacket platform, comprising the following specific steps:

[0008] Step 1: Collect environmental parameters, structural parameters and load parameters of the offshore jacket platform by conducting on-site exploration, measurement and analysis. The environmental parameters include wave height, current speed, wind speed and temperature. The structural parameters include strength data, stiffness data, yield strength and ultimate strength. The load parameters include static load and dynamic load.

[0009] Step 2: Generate the environmental impact index of the offshore jacket platform based on the dimensionless processed wave height, current speed, wind speed and temperature; generate the material impact index of the offshore jacket platform based on the dimensionless processed strength data, stiffness data, yield strength and ultimate strength; and generate the load index of the offshore jacket platform based on the dimensionless processed static load and dynamic load;

[0010] Step 3: The environmental impact index, material impact index and load index are integrated and correlation analysis is performed to obtain the integrated bearing capacity assessment index of the offshore jacket platform;

[0011] Step 4: Determine the ultimate bearing capacity of the offshore jacket platform based on the bearing capacity assessment index of the integrated offshore jacket platform and the safety factor of the material used in the jacket.

[0012] Furthermore, based on the real-time monitoring of the marine meteorological station, the wave height of the ocean surface near the marine jacket platform to be tested is obtained, denoted by H, in meters; the wind speed above the jacket is obtained, denoted by V, in meters / s; the ocean current speed below the marine jacket platform to be tested is obtained, denoted by U, in meters / s; and the water temperature is obtained, denoted by T, in degrees Celsius.

[0013] Further, the strength data is the ratio of the mass of steel bars and the mass of concrete used in the jacket-type platform structure, and the stiffness data includes the average elastic modulus and average Poisson's ratio of the steel and concrete used in the jacket-type platform;

[0014] The specific logic for collecting intensity data is:

[0015] Obtain the total concrete mass and total steel mass used to construct the jacket platform, and generate the ratio of the steel mass to the concrete mass used in the jacket platform structure, based on the formula:

[0016]

[0017] Among them, ρ is the strength data of the jacket platform, M g is the total steel mass used in the jacket platform, M h Total concrete mass used for the jacket type platform;

[0018] The specific logic for collecting the stiffness data of the jacket platform is as follows:

[0019]

[0020] Where σ is the average elastic modulus of the steel and concrete used in the jacket platform, EM g is the average elastic modulus of the steel used in the jacket platform, EM h The average elastic modulus of the concrete type used in the jacket type platform;

[0021]

[0022] Where τ is the average Poisson's ratio of steel and concrete used in the jacket platform, PR g is the average Poisson’s ratio of the steel types used in the jacket platform, PR h The average Poisson's ratio of the concrete type used for the jacket type platform;

[0023] The specific logic for collecting the yield strength of the jacket is as follows: determine the material used for the jacket, make a tensile test specimen according to the standard, install the test specimen on both sides of the hydraulic testing machine, clamp it, slowly apply tensile force, and record the corresponding strain, and calculate the stress using the following formula:

[0024]

[0025] Where ε is stress, F is applied force, and A0 is the original cross-sectional area of ​​the specimen;

[0026] When the stress reaches the yield point of the material, the material begins to undergo obvious plastic deformation. The stress value at this time is recorded and recorded as ε y , ε y It is the yield strength of the jacket;

[0027] The specific logic for collecting the ultimate strength of the jacket is as follows: based on the yield strength test, the tensile force is continued to be applied until the sample breaks, and the maximum stress value at the moment of breaking is recorded:

[0028]

[0029] Among them, ε u is the ultimate strength of the jacket, F max is the maximum applied force at fracture, and A0 is the original cross-sectional area of ​​the specimen.

[0030] Obtain all static loads borne by the jacket through the design drawings, including deadweight, equipment, pipelines and accumulated water. Add all static loads to obtain the total static load of the jacket, denoted as F static; Dynamic load refers to the instantaneous load caused by waves and wind speed. Sensors are used to monitor the dynamic load borne by the jacket in real time, denoted as F dynamic .

[0031] Furthermore, the formula for generating the environmental impact index is:

[0032]

[0033] Among them, ENV is the environmental impact index, H is the wave height, V is the wind speed, and U is the current speed. is an exponential growth function, which indicates the influence of water temperature on the environment. (T-25) indicates the difference between the current temperature and the ideal water temperature of 25 degrees Celsius. γ and ω are preset proportional coefficients, and γ>ω>0. C1 is the first constant correction exponent.

[0034] The material impact index is generated based on the formula:

[0035]

[0036] Among them, MAT is the material influence index, ρ is the strength data of the jacket platform, σ is the average elastic modulus of the steel and concrete used in the jacket platform, τ is the average Poisson's ratio of the steel and concrete used in the jacket platform, ε u is the ultimate strength of the jacket, α and β are preset proportional coefficients, and β>α>0, and C2 is the second constant correction index;

[0037] The generated load index is based on the formula:

[0038] LOA=μ*(F static +F dynamic )

[0039] Where LOA is the load index, F static is the static load, F dynamic is the dynamic load, and μ is the preset proportional coefficient.

[0040] Furthermore, the environmental impact index, material impact index and load index are integrated and correlation analysis is performed to obtain the integrated bearing capacity assessment index of the offshore jacket platform, which is specifically:

[0041]

[0042] Among them, QS is the bearing capacity assessment index, ENV is the environmental impact index, b is its preset proportional coefficient, MAT is the material impact index, a is its preset proportional coefficient, LOA is the load index, c is its preset proportional coefficient, and b>a>c>0, C3 is the third constant correction index.

[0043] Furthermore, the formula for determining the ultimate bearing capacity of the offshore jacket platform is as follows:

[0044]

[0045] Among them, ULT is the ultimate bearing capacity of the offshore jacket platform to be tested, QS is the bearing capacity assessment index of the offshore jacket platform to be tested, and SF is the safety factor;

[0046] The calculation formula of SF is:

[0047]

[0048] Here ε is the maximum stress measured by finite element analysis, and ε y is the yield strength.

[0049] The present invention further provides a system for determining the ultimate bearing capacity of an offshore jacket type platform, wherein the system for determining the ultimate bearing capacity of an offshore jacket type platform is used to execute the above-mentioned method for determining the ultimate bearing capacity of an offshore jacket type platform, and comprises:

[0050] A data acquisition module is used to collect environmental parameters, structural parameters and load parameters of the offshore jacket platform by conducting on-site exploration, measurement and analysis. The environmental parameters include wave height, current speed, wind speed and temperature. The structural parameters include strength data, stiffness data, yield strength and ultimate strength. The load parameters include static load and dynamic load.

[0051] The data analysis module generates the environmental impact index of the offshore jacket platform based on the dimensionless processed wave height, current speed, wind speed and temperature, generates the material impact index of the offshore jacket platform based on the dimensionless processed strength data, stiffness data, yield strength and ultimate strength, and generates the load index of the offshore jacket platform based on the dimensionless processed static load and dynamic load;

[0052] Index fusion module, used to fuse the environmental impact index, material impact index and load index, conduct correlation analysis, and obtain the fused bearing capacity assessment index of the offshore jacket platform;

[0053] The ultimate bearing capacity determination module determines the ultimate bearing capacity of the offshore jacket platform based on the integrated bearing capacity assessment index of the offshore jacket platform and the safety factor of the material used in the jacket.

[0054] Compared with the prior art, the present invention has the following beneficial effects:

[0055] The present invention proposes a new method for comprehensively evaluating the ultimate bearing capacity of an offshore jacket platform by systematically collecting and analyzing environmental parameters, structural parameters, and load parameters. This method integrates the environmental impact index, material impact index, and load index through dimensionless processing and correlation analysis, and can more accurately reflect the actual bearing capacity of the platform under complex marine conditions, thereby reducing design risks. In addition, the final bearing capacity is determined in combination with the material's safety factor, which improves the safety and reliability of the platform, helps reduce maintenance costs, and prolongs its service life. The implementation of this method will provide strong technical support for the design and construction of marine engineering and promote the sustainable development of marine resources. BRIEF DESCRIPTION OF THE DRAWINGS

[0056] Figure 1 It is a schematic diagram of the overall method flow of the present invention;

[0057] Figure 2 It is a schematic diagram of the overall system module of the present invention. DETAILED DESCRIPTION

[0058] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with specific embodiments.

[0059] It should be noted that, unless otherwise defined, the technical terms or scientific terms used in the present invention should be understood by people with ordinary skills in the field to which the present invention belongs. The words "first", "second" and similar words used in the present invention do not indicate any order, quantity or importance, but are only used to distinguish different components. "Include" or "comprise" and similar words mean that the elements or objects appearing before the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects. "Connect" or "connected" and similar words are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0060] Example:

[0061] See also Figure 1 , the present invention provides a technical solution:

[0062] A method for determining the ultimate bearing capacity of an offshore jacket platform, comprising the following specific steps:

[0063] Step 1: Collect environmental parameters, structural parameters and load parameters of the offshore jacket platform by conducting on-site exploration, measurement and analysis. The environmental parameters include wave height, current speed, wind speed and temperature. The structural parameters include strength data, stiffness data, yield strength and ultimate strength. The load parameters include static load and dynamic load.

[0064] In this embodiment, based on the real-time monitoring of the marine meteorological station, the wave height of the ocean surface near the marine jacket type platform to be tested is obtained, which is recorded as H and the unit is m; the wind speed above the jacket is obtained, which is recorded as V and the unit is m / s; the ocean current speed below the marine jacket type platform to be tested is obtained, which is recorded as U and the unit is m / s; and the water temperature is obtained, which is recorded as t and the unit is ° C.

[0065] The strength data is the ratio of the mass of steel bars and the mass of concrete used in the jacket-type platform structure, and the stiffness data includes the average elastic modulus and average Poisson's ratio of the steel and concrete used in the jacket-type platform;

[0066] The specific logic for collecting intensity data is:

[0067] Obtain the total concrete mass and total steel mass used to construct the jacket platform, and generate the ratio of the steel mass to the concrete mass used in the jacket platform structure, based on the formula:

[0068]

[0069] Among them, ρ is the strength data of the jacket platform, M g is the total steel mass used in the jacket platform, M h Total concrete mass used for the jacket type platform;

[0070] The specific logic for collecting the stiffness data of the jacket platform is as follows:

[0071]

[0072] Where σ is the average elastic modulus of the steel and concrete used in the jacket platform, EM g is the average elastic modulus of the steel used in the jacket platform, EM h The average elastic modulus of the concrete type used in the jacket type platform;

[0073]

[0074] Where τ is the average Poisson's ratio of steel and concrete used in the jacket platform, PR g is the average Poisson’s ratio of the steel types used in the jacket platform, PR hThe average Poisson's ratio of the concrete type used for the jacket type platform;

[0075] The specific logic for collecting the yield strength of the jacket is as follows: determine the material used for the jacket, make a tensile test specimen according to the standard, install the test specimen on both sides of the hydraulic testing machine, clamp it, slowly apply tensile force, and record the corresponding strain, and calculate the stress using the following formula:

[0076]

[0077] Where ε is stress, F is applied force, and A0 is the original cross-sectional area of ​​the specimen;

[0078] When the stress reaches the yield point of the material, the material begins to undergo obvious plastic deformation. The stress value at this time is recorded and recorded as ε y , ε y It is the yield strength of the jacket;

[0079] The specific logic for collecting the ultimate strength of the jacket is as follows: based on the yield strength test, the tensile force is continued to be applied until the sample breaks, and the maximum stress value at the moment of breaking is recorded:

[0080]

[0081] Among them, ε u is the ultimate strength of the jacket, F max is the maximum applied force at fracture, and A0 is the original cross-sectional area of ​​the specimen.

[0082] Obtain all static loads borne by the jacket through the design drawings, including deadweight, equipment, pipelines and accumulated water. Add all static loads to obtain the total static load of the jacket, denoted as F static ; Dynamic load refers to the instantaneous load caused by waves and wind speed. Sensors are used to monitor the dynamic load borne by the jacket in real time, denoted as F dynamic .

[0083] Step 1 systematically collects environmental parameters, structural parameters and load parameters of the offshore jacket platform through comprehensive exploration, measurement and analysis of the site. This comprehensive data collection method can ensure the accurate grasp of the actual operating environment of the platform and avoid the uncertainty caused by simple assumptions. Compared with the existing technology, this step provides a more detailed information basis, which greatly enhances the scientificity and accuracy of the subsequent evaluation process. Compared with the empirical method and simplified model commonly used in the existing technology, step 1 emphasizes the authenticity and diversity of the data, and can effectively reflect the impact of the complex marine environment on the platform's bearing capacity. This methodological shift makes the design stage not only rely on theoretical formulas, but also combine actual data for evaluation, thereby reducing design risks and improving the safety and reliability of the platform. After adopting step 1, the entire solution is more solid on the basis of data, which is conducive to the subsequent dimensionless processing and the generation of bearing capacity evaluation index. This step ensures that the correlation analysis between different parameters can be carried out under real environmental conditions, thereby facilitating the accurate calculation of the ultimate ultimate bearing capacity.

[0084] Step 2: Generate the environmental impact index of the offshore jacket platform based on the dimensionless processed wave height, current speed, wind speed and temperature; generate the material impact index of the offshore jacket platform based on the dimensionless processed strength data, stiffness data, yield strength and ultimate strength; and generate the load index of the offshore jacket platform based on the dimensionless processed static load and dynamic load;

[0085] In this embodiment, the formula for generating the environmental impact index is:

[0086]

[0087] Among them, ENV is the environmental impact index, H is the wave height, V is the wind speed, and U is the current speed. is an exponential growth function, which indicates the influence of water temperature on the environment. (T-25) indicates the difference between the current temperature and the most ideal water temperature of 25 degrees Celsius. γ and ω are preset proportional coefficients, and γ>ω>0. This is because in the marine environment, wave height often has the greatest impact on the platform structure, especially in deep water areas. The load caused by the dynamic action of waves is usually very significant, so its weight is relatively large. C1 is the first constant correction index. Higher waves will increase the dynamic load of the platform. Therefore, when H increases, the environmental impact index ENV increases. An increase in wind speed will cause an increase in wind load. An increase in current speed may lead to greater hydrodynamic loads, especially the additional loads caused by the relative motion between the platform and the fluid. Therefore, when V and U increase, the environmental impact index ENV increases. High temperature may cause material softening, reduce yield strength, and thus reduce the ultimate bearing capacity. Low temperature environment may cause material brittleness and increase the risk of fracture. That is, H, V, and U are positively correlated with the environmental impact index ENV.

[0088] The material impact index is generated based on the formula:

[0089]

[0090] Among them, MAT is the material influence index, ρ is the strength data of the jacket platform, σ is the average elastic modulus of the steel and concrete used in the jacket platform, τ is the average Poisson's ratio of the steel and concrete used in the jacket platform, ε u is the ultimate strength of the jacket, α and β are preset proportional coefficients, and β>α>0. This is because the ultimate strength is directly related to the bearing capacity and safety of the structure under extreme load conditions, and determines whether the jacket can safely withstand various stresses and load ultimate strengths in actual applications. C2 is the second constant correction index;

[0091] The generated load index is based on the formula:

[0092] LOA=μ*(F static +F dynamic )

[0093] Where LOA is the load index, F static is the static load, F dynamic is the dynamic load, and μ is the preset proportional coefficient.

[0094] Step 3: The environmental impact index, material impact index and load index are integrated and correlation analysis is performed to obtain the integrated bearing capacity assessment index of the offshore jacket platform;

[0095] In this embodiment, the environmental impact index, material impact index and load index are integrated to perform correlation analysis to obtain the integrated bearing capacity assessment index of the offshore jacket platform, which is specifically:

[0096]

[0097] Among them, QS is the bearing capacity assessment index, ENV is the environmental impact index, b is its preset proportional coefficient, MAT is the material impact index, a is its preset proportional coefficient, LOA is the load index, c is its preset proportional coefficient, and b>a>c>0, because the marine environmental conditions have a direct impact on the ultimate bearing capacity of the platform, especially under extreme weather conditions. The uncertainty and variability of environmental factors may lead to unexpected load balancing and impact, and C3 is the third constant correction index; when ENV increases, it means that the impact of the environment on the platform becomes greater, and the bearing capacity assessment index QS decreases; when LOA increases, it means that the load borne by the platform becomes greater, and the bearing capacity assessment index QS decreases; when MAT increases, it means that the performance of the construction material is better, and the bearing capacity assessment index QS increases; that is, MAT is positively correlated with QS, and ENV, LOA and QS are negatively correlated.

[0098] Step 4: Determine the ultimate bearing capacity of the offshore jacket platform based on the combined bearing capacity assessment index of the offshore jacket platform and the safety factor of the material used in the jacket;

[0099] In this embodiment, the formula for determining the ultimate bearing capacity of the offshore jacket platform is as follows:

[0100]

[0101] Among them, ULT is the ultimate bearing capacity of the offshore jacket platform to be tested, QS is the bearing capacity assessment index of the offshore jacket platform to be tested, and SF is the safety factor;

[0102] The calculation formula of SF is:

[0103]

[0104] Here ε is the maximum stress measured by finite element analysis, and ε y is the yield strength.

[0105] Step 4 combines the fused bearing capacity assessment index with the material safety factor to form a comprehensive method for determining the ultimate bearing capacity. This method aims to make the final bearing capacity assessment more reliable and practical through scientific data analysis. Compared with the existing methods that rely solely on empirical formulas or static analysis, this step can comprehensively consider dynamic factors and material properties to provide a more accurate safety assessment. Compared with the existing technology, step 4 introduces the concept of safety factor to make the assessment results more in line with the safety requirements in actual operations. This method not only enhances the multi-dimensional understanding of bearing capacity assessment, but also effectively reduces the potential risks caused by environmental changes or uncertainty in material properties, providing a more comprehensive guarantee for engineering safety. In the overall solution, the implementation of step 4 provides key decision-making basis for each link, ensuring that the comprehensive analysis from environment, materials to loads can be effectively transformed into practical design standards. The addition of this step makes the entire bearing capacity assessment process more systematic and scientific, and improves the overall applicability and industry value of the solution.

[0106] See also Figure 2 The present invention also provides a system for determining the ultimate bearing capacity of an offshore jacket platform, comprising:

[0107] A data acquisition module is used to collect environmental parameters, structural parameters and load parameters of the offshore jacket platform by conducting on-site exploration, measurement and analysis. The environmental parameters include wave height, current speed, wind speed and temperature. The structural parameters include strength data, stiffness data, yield strength and ultimate strength. The load parameters include static load and dynamic load.

[0108] The data analysis module generates the environmental impact index of the offshore jacket platform based on the dimensionless processed wave height, current speed, wind speed and temperature, generates the material impact index of the offshore jacket platform based on the dimensionless processed strength data, stiffness data, yield strength and ultimate strength, and generates the load index of the offshore jacket platform based on the dimensionless processed static load and dynamic load;

[0109] Index fusion module, used to fuse the environmental impact index, material impact index and load index, conduct correlation analysis, and obtain the fused bearing capacity assessment index of the offshore jacket platform;

[0110] The ultimate bearing capacity determination module determines the ultimate bearing capacity of the offshore jacket platform based on the integrated bearing capacity assessment index of the offshore jacket platform and the safety factor of the material used in the jacket.

[0111] The specific values ​​of a, b, c, α, β, γ, μ and ω in the formula are generally determined by technical personnel in this field according to actual conditions. The technical personnel in this field collect multiple groups of sample data, and set corresponding preset proportional coefficients for each group of sample data. The preset proportional coefficients and the collected sample data are substituted into the formula. Through repeated experiments and parameter adjustments, the accuracy of the model output and the rationality of the results are observed, and these factor coefficients are gradually adjusted. The performance and effect of the model under different parameter settings are compared to find the optimal coefficient combination. The calculated factor coefficients are screened and averaged to obtain the values ​​of a, b, c, α, β, γ, μ and ω.

[0112] In addition, the size of the preset factor coefficient is to quantify each parameter to obtain a specific value. In order to facilitate subsequent comparison, the size of the coefficient depends on the amount of sample data and the preset proportional coefficient initially set by technical personnel in this field for each set of sample data. It is not unique as long as it does not affect the proportional relationship between the parameter and the quantized value.

[0113] The above formulas are all dimensionless and numerical calculations. The formula is a formula for the most recent real situation obtained by collecting a large amount of data and performing software simulation. The preset parameters in the formula are set by technicians in this field according to actual conditions.

[0114] The above embodiments may be implemented in whole or in part by software, hardware, firmware or any other combination thereof. When implemented by software, the above embodiments may be implemented in whole or in part in the form of a computer program product. Those skilled in the art may appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein may be implemented by electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed by hardware or software methods depends on the specific application and design constraints of the technical solution.

[0115] 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, and 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.

[0116] The above description is only a specific implementation manner of the present application, but the protection scope of the present application is not limited thereto. Any technician familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application.

Claims

1. A method for determining the ultimate bearing capacity of an offshore jacket platform, characterized in that: The specific steps include: Step 1: Collect environmental parameters, structural parameters and load parameters of the offshore jacket platform by conducting on-site exploration, measurement and analysis. The environmental parameters include wave height, current speed, wind speed and temperature. The structural parameters include strength data, stiffness data, yield strength and ultimate strength. The load parameters include static load and dynamic load. Step 2: Generate the environmental impact index of the offshore jacket platform based on the dimensionless processed wave height, current speed, wind speed and temperature; generate the material impact index of the offshore jacket platform based on the dimensionless processed strength data, stiffness data, yield strength and ultimate strength; and generate the load index of the offshore jacket platform based on the dimensionless processed static load and dynamic load; Step 3: The environmental impact index, material impact index and load index are integrated and correlation analysis is performed to obtain the integrated bearing capacity assessment index of the offshore jacket platform; Step 4: Determine the ultimate bearing capacity of the offshore jacket platform based on the bearing capacity assessment index of the integrated offshore jacket platform and the safety factor of the material used in the jacket.

2. The method for determining the ultimate bearing capacity of an offshore jacket platform according to claim 1, characterized in that: According to the real-time monitoring of the marine meteorological station, the wave height of the ocean surface near the marine jacket platform to be tested is obtained, which is recorded as H in m; the wind speed above the jacket is obtained, which is recorded as V in m / s; the current speed below the marine jacket platform to be tested is obtained, which is recorded as U in m / s; the water temperature is obtained, which is recorded as T in ℃.

3. The method for determining the ultimate bearing capacity of an offshore jacket platform according to claim 1, characterized in that: The strength data is the ratio of the mass of steel bars and the mass of concrete used in the jacket-type platform structure, and the stiffness data includes the average elastic modulus and average Poisson's ratio of the steel and concrete used in the jacket-type platform; The specific logic for collecting intensity data is: Obtain the total concrete mass and total steel mass used to construct the jacket platform, and generate the ratio of the steel mass to the concrete mass used in the jacket platform structure, based on the formula: Among them, ρ is the strength data of the jacket platform, M g is the total steel mass used in the jacket platform, M h Total concrete mass used for the jacket type platform; The specific logic for collecting the stiffness data of the jacket platform is as follows: Where σ is the average elastic modulus of the steel and concrete used in the jacket platform, EM g is the average elastic modulus of the steel used in the jacket platform, EM h The average elastic modulus of the concrete type used in the jacket type platform; Where τ is the average Poisson's ratio of steel and concrete used in the jacket platform, PR g is the average Poisson’s ratio of the steel types used in the jacket platform, PR h The average Poisson's ratio of the concrete type used for the jacket type platform; The specific logic for collecting the yield strength of the jacket is as follows: determine the material used for the jacket, make a tensile test specimen according to the standard, install the test specimen on both sides of the hydraulic testing machine, clamp it, slowly apply tensile force, and record the corresponding strain, and calculate the stress using the following formula: Where ε is stress, F is applied force, and A0 is the original cross-sectional area of ​​the specimen; When the stress reaches the yield point of the material, the material begins to undergo obvious plastic deformation. The stress value at this time is recorded and recorded as ε y , ε y It is the yield strength of the jacket; The specific logic for collecting the ultimate strength of the jacket is as follows: based on the yield strength test, the tensile force is continued to be applied until the sample breaks, and the maximum stress value at the moment of breaking is recorded: Among them, ε u is the ultimate strength of the jacket, F max is the maximum applied force at fracture, A0 is the original cross-sectional area of ​​the specimen; Obtain all static loads borne by the jacket through the design drawings, including deadweight, equipment, pipelines and accumulated water. Add all static loads to obtain the total static load of the jacket, denoted as F static ; Dynamic load refers to the instantaneous load caused by waves and wind speed. Sensors are used to monitor the dynamic load borne by the jacket in real time, denoted as F dtnamic .

4. The method for determining the ultimate bearing capacity of an offshore jacket platform according to claim 1, characterized in that: The formula for generating the environmental impact index is: Among them, ENV is the environmental impact index, H is the wave height, V is the wind speed, and U is the current speed. is an exponential growth function, which indicates the influence of water temperature on the environment. (T-25) indicates the difference between the current temperature and the ideal water temperature of 25 degrees Celsius. γ and ω are preset proportional coefficients, and γ>ω>0. C1 is the first constant correction exponent. The material impact index is generated based on the formula: Among them, MAT is the material influence index, ρ is the strength data of the jacket platform, σ is the average elastic modulus of the steel and concrete used in the jacket platform, τ is the average Poisson's ratio of the steel and concrete used in the jacket platform, ε u is the ultimate strength of the jacket, α and β are preset proportional coefficients, and β>α>0, and C2 is the second constant correction index; The generated load index is based on the formula: LOA=μ*(F static +F dynamic ) Where LOA is the load index, F static is the static load, F dynamic is the dynamic load, and μ is the preset proportional coefficient.

5. The method for determining the ultimate bearing capacity of an offshore jacket platform according to claim 4, characterized in that: The environmental impact index, material impact index and load index are integrated and correlation analysis is performed to obtain the integrated bearing capacity assessment index of the offshore jacket platform, which is specifically: Among them, QS is the bearing capacity assessment index, ENV is the environmental impact index, b is its preset proportional coefficient, MAT is the material impact index, a is its preset proportional coefficient, LOA is the load index, c is its preset proportional coefficient, and b>a>c>0, C3 is the third constant correction index.

6. The method for determining the ultimate bearing capacity of an offshore jacket platform according to claim 5, characterized in that: The formula for determining the ultimate bearing capacity of the offshore jacket platform is as follows: Among them, ULT is the ultimate bearing capacity of the offshore jacket platform to be tested, QS is the bearing capacity assessment index of the offshore jacket platform to be tested, and SF is the safety factor; The calculation formula of SF is: Here ε is the maximum stress measured by finite element analysis, and ε y is the yield strength.

7. A system for determining the ultimate bearing capacity of an offshore jacket platform, characterized in that: The ultimate bearing capacity determination system of an offshore jacket type platform is used to execute the ultimate bearing capacity determination method of an offshore jacket type platform according to any one of claims 1 to 6, comprising: A data acquisition module is used to collect environmental parameters, structural parameters and load parameters of the offshore jacket platform by conducting on-site exploration, measurement and analysis. The environmental parameters include wave height, current speed, wind speed and temperature. The structural parameters include strength data, stiffness data, yield strength and ultimate strength. The load parameters include static load and dynamic load. The data analysis module generates the environmental impact index of the offshore jacket platform based on the dimensionless processed wave height, current speed, wind speed and temperature, generates the material impact index of the offshore jacket platform based on the dimensionless processed strength data, stiffness data, yield strength and ultimate strength, and generates the load index of the offshore jacket platform based on the dimensionless processed static load and dynamic load; Index fusion module, used to fuse the environmental impact index, material impact index and load index, conduct correlation analysis, and obtain the fused bearing capacity assessment index of the offshore jacket platform; The ultimate bearing capacity determination module determines the ultimate bearing capacity of the offshore jacket platform based on the integrated bearing capacity assessment index of the offshore jacket platform and the safety factor of the material used in the jacket.

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