Method and system for determining ultimate bearing capacity of an offshore jacket platform

Abstract

The present invention provides a method and system for determining the ultimate bearing capacity of an offshore jacket-type platform, which relates to the field of offshore engineering technology. The specific steps include: collecting the environmental parameters, structural parameters, and load parameters of the platform; generating corresponding environmental impact indices, material impact indices, and load indices based on dimensionless processing; performing fusion and correlation analysis on these three indices to obtain a comprehensive bearing capacity evaluation index; and determining the ultimate bearing capacity of the offshore jacket-type platform by combining the bearing capacity evaluation index and the safety factor of the material. Through dimensionless processing and correlation analysis, the present invention fuses the environmental impact index, material impact index, and load index, which can more accurately reflect the actual bearing capacity of the platform under complex marine conditions, thereby reducing the design risk. In addition, the determination of the final bearing capacity by combining the safety factor of the material improves the safety and reliability of the platform, helps to reduce the maintenance cost and extend the service life.

Description

Technical Field

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

[0002] In the process of ocean resource development, as a key infrastructure, the safety and bearing capacity assessment of offshore jacket platforms are of crucial importance. 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 ocean currents in the marine environment, as well as the variability of these factors over time, resulting in insufficient prediction of potential limit conditions during design. In addition, existing methods often use simplified material property models, which cannot fully reflect the true performance of materials under different environmental conditions. For example, how the strength and toughness of materials change under extreme temperatures or high corrosion environments, which may lead to sudden failures at critical moments.

[0003] Furthermore, when many existing technologies conduct ultimate bearing capacity assessment, they lack a comprehensive analysis of load changes, especially the consideration of dynamic loads is insufficient. The changes in wave action, wind loads, and ocean current forces in the marine environment are important factors affecting the safety of the platform, 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 stage. Therefore, there is an urgent need for a more systematic and comprehensive assessment method to overcome these technical deficiencies and ensure the safety and reliability of offshore jacket platforms during actual operation.

[0004] The above information disclosed in the background art section is only used to enhance the understanding of the background of the present disclosure, and therefore it may include information that does not constitute the prior art known to those of ordinary skill in the art. Summary of the Invention

[0005] The purpose of the present invention is to provide a method and system for determining the ultimate bearing capacity of an offshore jacket platform to solve the problems raised in the above background art.

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

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

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

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

[0010] Step 3: Integrate the environmental impact index, material impact index, and load index, and conduct a correlation analysis to obtain the bearing capacity evaluation index of the integrated offshore jacket platform.

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

[0012] Furthermore, based on the real-time monitoring of the ocean weather station, obtain the wave height on the ocean surface near the offshore jacket platform to be measured, denoted as H, with the unit of m; obtain the wind speed above the jacket, denoted as V, with the unit of m / s; obtain the sea current velocity below the offshore jacket platform to be measured, denoted as U, with the unit of m / s; obtain the water temperature, denoted as T, with the unit of °C.

[0013] Furthermore, the strength data is the ratio of the mass of steel bars to the mass of concrete used in the structure of the jacket platform. The stiffness data includes the average elastic modulus and average Poisson's ratio of the steel and concrete used in the jacket platform.

[0014] The specific logic for collecting strength data is as follows:

[0015] Obtain the total mass of concrete and the total mass of steel bars used in constructing the jacket platform, and generate the ratio of the mass of steel bars to the mass of concrete used in the structure of the jacket platform. The formula is as follows:

[0016]

[0017] where ρ is the strength data of the jacket platform, M g is the total mass of steel bars used in the jacket platform, and M h is the total mass of concrete used in the jacket platform.

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

[0019]

[0020] Among them, σ is the average elastic modulus of the steel and concrete used in the jacket-type platform, EM g is the average elastic modulus of the steel types used in the jacket-type platform, EM h is the average elastic modulus of the concrete types used in the jacket-type platform;

[0021]

[0022] Among them, τ is the average Poisson's ratio of the steel and concrete used in the jacket-type platform, PR g is the average Poisson's ratio of the steel types used in the jacket-type platform, PR h is the average Poisson's ratio of the concrete types used in the jacket-type platform;

[0023] The specific logic for collecting the yield strength of the jacket is as follows: Determine the materials used for the jacket, fabricate tensile specimens according to standards, install the specimens on both sides of a hydraulic testing machine and clamp them tightly, slowly apply a tensile force, and record the corresponding strain. Calculate the stress using the following formula:

[0024]

[0025] Among them, ε is the stress, F is the 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. Record the stress value at this time, denoted as ε y ε y is the yield strength of the jacket;

[0027] The specific logic for collecting the ultimate strength of the jacket is as follows: On the basis of the yield strength test, continue to apply a tensile force until the specimen fractures, and record the maximum stress value at the moment of fracture:

[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 the static loads borne by the jacket from the design drawings, including self-weight, equipment, pipelines, and accumulated water. Add up all the static loads to obtain the total static load of the jacket, denoted as F static; The dynamic load refers to the instantaneous variable load caused by waves and wind speed. The dynamic load borne by the jacket is monitored in real time using sensors and denoted as F dynamic .

[0031] Furthermore, an environmental impact index is generated according to the following formula:

[0032]

[0033] where ENV is the environmental impact index, H is the wave height, V is the wind speed, U is the ocean current speed, is an exponential growth function representing the impact of water temperature on the environment, (T - 25) represents the difference between the current temperature and the ideal water temperature of 25 °C, γ and ω are preset proportionality coefficients with γ > ω > 0, and C1 is the first constant correction exponent;

[0034] A material impact index is generated according to the following formula:

[0035]

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

[0037] A load index is generated according to the following 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 a preset proportionality coefficient.

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

[0041]

[0042] where QS is the bearing capacity evaluation index, ENV is the environmental impact index, b is its preset proportionality coefficient, MAT is the material impact index, a is its preset proportionality coefficient, LOA is the load index, c is its preset proportionality coefficient, and b > a > c > 0, and C3 is the third constant correction exponent.

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

[0044]

[0045] Where ULT is the ultimate bearing capacity of the offshore jacket platform to be measured, QS is the bearing capacity evaluation index of the offshore jacket platform to be measured, and SF is the safety factor;

[0046] The calculation formula of SF is:

[0047]

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

[0049] The present invention also provides an ultimate bearing capacity determination system for an offshore jacket platform. The ultimate bearing capacity determination system for an offshore jacket platform is used to execute the above-mentioned ultimate bearing capacity determination method for an offshore jacket platform, and includes:

[0050] A data acquisition module, which is used to collect environmental parameters, structural parameters and load parameters of the offshore jacket platform by exploring, measuring and analyzing the site. The environmental parameters are wave height, sea current velocity, wind speed and temperature, the structural parameters are strength data, stiffness data, yield strength and ultimate strength, and the load parameters are static load and dynamic load;

[0051] A data analysis module, which generates an environmental impact index for the offshore jacket platform based on the dimensionless wave height, sea current velocity, wind speed and temperature, generates a material impact index for the offshore jacket platform based on the dimensionless strength data, stiffness data, yield strength and ultimate strength, and generates a load index for the offshore jacket platform based on the dimensionless static load and dynamic load;

[0052] An index fusion module, which is used to fuse the environmental impact index, the material impact index and the load index, perform correlation analysis, and obtain the bearing capacity evaluation index of the fused offshore jacket platform;

[0053] An ultimate bearing capacity determination module, which determines the ultimate bearing capacity of the offshore jacket platform according to the bearing capacity evaluation index of the fused offshore jacket platform and the safety factor of the material used for the jacket.

[0054] Compared with the prior art, the beneficial effects of the present invention are:

[0055] By systematically collecting and analyzing environmental parameters, structural parameters, and load parameters, the present invention proposes a new method for comprehensively evaluating the ultimate bearing capacity of offshore jacket platforms. Through dimensionless processing and correlation analysis, this method integrates the environmental impact index, material impact index, and load index, and can more accurately reflect the actual bearing capacity of the platform under complex marine conditions, thereby reducing design risks. In addition, by combining the safety factor of the material to determine the ultimate bearing capacity, the safety and reliability of the platform are improved, which helps to reduce maintenance costs and extend the service life. The implementation of this method will provide strong technical support for the design and construction in the field of ocean engineering and promote the sustainable development of marine resources. BRIEF DESCRIPTION OF THE DRAWINGS

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

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

[0058] To make the objectives, technical solutions, and advantages of the present invention clearer and more understandable, the present invention will be 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 have the ordinary meanings understood by those of ordinary skill in the field to which the present invention belongs. The "first", "second", and similar terms used in the present invention do not indicate any order, quantity, or importance, but are only used to distinguish different components. The terms such as "including" or "comprising" mean that the elements or objects appearing before this term cover the elements or objects listed after this term and their equivalents, without excluding other elements or objects. The terms such as "connected" or "coupled" are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. The terms such as "upper", "lower", "left", "right", etc. are only used to represent relative positional relationships, and when the absolute position of the object being described changes, the relative positional relationship may also change accordingly.

[0060] Embodiment:

[0061] Please refer to Figure 1 , the present invention provides a technical solution:

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

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

[0064] In this embodiment, based on the real-time monitoring of the marine weather station, obtain the wave height on the ocean surface near the offshore jacket platform to be measured, denoted as H, with the unit of m; obtain the wind speed above the jacket, denoted as V, with the unit of m / s; obtain the sea current velocity below the offshore jacket platform to be measured, denoted as U, with the unit of m / s; obtain the water temperature, denoted as T, with the unit of °C.

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

[0066] The specific logic for collecting the strength data is as follows:

[0067] Obtain the total mass of concrete and the total mass of steel bars used in constructing the jacket platform, and generate the ratio of the mass of steel bars to the mass of concrete used in the structure of the jacket platform. The formula is as follows:

[0068]

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

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

[0071]

[0072] Among them, 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 types used in the jacket platform, EM h is the average elastic modulus of the concrete types used in the jacket platform;

[0073]

[0074] Among them, τ is the average Poisson's ratio of the 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 types used in jacket platforms;

[0075] The specific logic for collecting the yield strength of the jacket is as follows: Determine the material used for the jacket, fabricate tensile specimens according to standards, install the specimens on both sides of a hydraulic testing machine and clamp them tightly, slowly apply a tensile force, and record the corresponding strain. Calculate the stress using the following formula:

[0076]

[0077] where ε is the stress, F is the 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. Record the stress value at this time, denoted as ε y , ε y is the yield strength of the jacket;

[0079] The specific logic for collecting the ultimate strength of the jacket is as follows: On the basis of the yield strength test, continue to apply a tensile force until the specimen fractures, and record the maximum stress value at the moment of fracture:

[0080]

[0081] where 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 the static loads borne by the jacket from the design drawings, including self-weight, equipment, pipelines, and accumulated water. Add up all the static loads to get the total static load of the jacket, denoted as F static ; Dynamic loads refer to the instantaneous variable loads caused by waves and wind speeds. Use sensors to monitor the dynamic loads borne by the jacket in real time, denoted as F dynamic .

[0083] Step 1 systematically collected the environmental parameters, structural parameters, and load parameters of the offshore jacket platform through comprehensive on-site exploration, measurement, and analysis. This comprehensive data collection method can ensure an accurate understanding of the actual operating environment of the platform, avoiding the uncertainties brought by simple assumptions. Compared with the existing technologies, this step provides a more detailed information basis, greatly enhancing the scientificity and accuracy of the subsequent evaluation process. Compared with the commonly used empirical methods and simplified models in the existing technologies, Step 1 emphasizes the authenticity and diversity of data, and can effectively reflect the impact of the complex marine environment on the platform's bearing capacity. This methodological transformation enables the design stage to not only rely on theoretical formulas but also combine actual data for evaluation, thereby reducing design risks and enhancing the safety and reliability of the platform. After adopting Step 1, the entire scheme is more solid based on data, which helps with subsequent dimensionless processing and the generation of the bearing capacity evaluation index. This step ensures that the correlation analysis between different parameters can be carried out under real environmental conditions, thus promoting the accurate calculation of the ultimate ultimate bearing capacity.

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

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

[0086]

[0087] where ENV is the environmental impact index, H is the wave height, V is the wind speed, U is the sea current velocity, It is an exponential growth function representing the impact of water temperature on the environment. (T - 25) represents the difference between the current temperature and the ideal water temperature of 25 degrees Celsius. γ and ω are preset proportionality 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 waters, the dynamic action of waves usually causes extremely significant loads, so its weight is relatively large. C1 is the first constant correction exponent; Higher waves will increase the dynamic load of the platform. Therefore, when H increases, the environmental impact index ENV increases; The increase in wind speed will cause an increase in wind load, and the increase in sea current speed may lead to greater hydrodynamic loads, especially the additional loads caused by the relative movement between the platform and the fluid. Therefore, when V and U increase, the environmental impact index ENV increases; High temperature may cause material softening and reduce the yield strength, thereby reducing the ultimate bearing capacity. Low temperature environment may cause material embrittlement and increase the risk of fracture; That is to say, H, V, and U are positively correlated with the environmental impact index ENV.

[0088] The formula for generating the material impact index is as follows:

[0089]

[0090] Among them, MAT is the material impact 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 proportionality 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 limits in actual applications. C2 is the second constant correction exponent;

[0091] The formula for generating the load index is as follows:

[0092] LOA = μ * (F static + F dynamic )

[0093] Among them, LOA is the load index, F static is the static load, F dynamic is the dynamic load, and μ is a preset proportionality coefficient.

[0094] Step 3: Integrate the environmental impact index, material impact index, and load index, conduct a correlation analysis, and obtain the bearing capacity evaluation index of the integrated jacket platform for the ocean.

[0095] In this embodiment, the environmental impact index, material impact index, and load index are fused to perform a correlation analysis to obtain the bearing capacity evaluation index of the offshore jacket platform after fusion, specifically as follows:

[0096]

[0097] Among them, QS is the bearing capacity evaluation 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. This is 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 impacts. 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 evaluation index QS decreases; when LOA increases, it means that the load borne by the platform becomes greater, and the bearing capacity evaluation index QS decreases; when MAT increases, it means that the performance of the construction material is better, and the bearing capacity evaluation index QS increases; that is to say, MAT is positively correlated with QS, and ENV and LOA are negatively correlated with QS.

[0098] Step 4: Determine the ultimate bearing capacity of the offshore jacket platform based on the bearing capacity evaluation index of the fused offshore jacket platform and the safety factor of the material used for 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 measured, QS is the bearing capacity evaluation index of the offshore jacket platform to be measured, and SF is the safety factor;

[0102] The calculation formula for SF is:

[0103]

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

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

[0106] Please refer to Figure 2 , the present invention also provides a system for determining the ultimate bearing capacity of an offshore jacket platform, including:

[0107] A data acquisition module for collecting environmental parameters, structural parameters, and load parameters of the offshore jacket platform by conducting exploration, measurement, and analysis on-site. The environmental parameters are wave height, sea current velocity, wind speed, and temperature. The structural parameters are strength data, stiffness data, yield strength, and ultimate strength. The load parameters are static load and dynamic load;

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

[0109] An index fusion module for fusing the environmental impact index, material impact index, and load index, conducting correlation analysis, and obtaining the fused bearing capacity evaluation index of the offshore jacket platform;

[0110] An ultimate bearing capacity determination module for determining the ultimate bearing capacity of the offshore jacket platform based on the fused bearing capacity evaluation index of the offshore jacket platform and the safety factor of the material used for the jacket.

[0111] The specific values of a, b, c, α, β, γ, μ, and ω in the formula are generally determined by those skilled in the art according to the actual situation. Those skilled in the art collect multiple sets of sample data, set corresponding preset proportionality coefficients for each set of sample data, substitute the set preset proportionality coefficients and the collected sample data into the formula, and through repeated experiments and parameter adjustments, observe the accuracy of the model output and the rationality of the results, gradually adjust these factor coefficients, compare the performance and effects of the model under different parameter settings, find the optimal coefficient combination, screen the calculated factor coefficients and take the average value to obtain the values of a, b, c, α, β, γ, μ, and ω.

[0112] In addition, the magnitude of the preset factor coefficient is a specific value obtained by quantifying each parameter. It is for the convenience of subsequent comparison. Regarding the magnitude of the coefficient, it depends on the amount of sample data and the corresponding preset proportionality coefficients initially set by those skilled in the art for each set of sample data, and it is not unique as long as it does not affect the proportional relationship between the parameter and the quantified value.

[0113] The above formulas are all dimensionless and take their numerical calculations. The formula is a formula obtained by collecting a large amount of data for software simulation to approximate the real situation as closely as possible. The preset parameters in the formula are set by those skilled in the art according to the actual situation.

[0114] The above embodiments can be implemented in whole or in part by software, hardware, firmware, or any other combination. When implemented using software, the above embodiments can be implemented in whole or in part in the form of a computer program product. Those skilled in the art can realize that the units and algorithm steps of each example described in conjunction with the embodiments disclosed in this article can be implemented by electronic hardware or a combination of computer software and electronic hardware. Whether these functions are executed 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. The components shown as units may or may not be physical units. They can be located in one place or distributed to multiple network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0116] The above is only the specific implementation manner of this application, but the protection scope of this application is not limited thereto. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed in this application, and all should be covered by the protection scope of this application.

Claims

1. A method for determining the ultimate bearing capacity of an offshore jacket-type platform, characterized in that, The specific steps include: Step 1: By conducting on-site exploration, measurement, and analysis, collect the environmental parameters, structural parameters, and load parameters of the offshore jacket platform. The environmental parameters are wave height, sea current velocity, wind speed, and temperature. The structural parameters are strength data, stiffness data, yield strength, and ultimate strength. The load parameters are static load and dynamic load. Step 2: Based on the dimensionless wave height, sea current velocity, wind speed, and temperature, generate the environmental impact index of the offshore jacket platform. Based on the dimensionless strength data, stiffness data, yield strength, and ultimate strength, generate the material impact index of the offshore jacket platform. Based on the dimensionless static load and dynamic load, generate the load index of the offshore jacket platform. Step 3: Integrate the environmental impact index, material impact index, and load index, and conduct a correlation analysis to obtain the bearing capacity evaluation index of the integrated offshore jacket platform. Step 4: Determine the ultimate bearing capacity of the offshore jacket platform based on the bearing capacity evaluation index of the integrated offshore jacket platform and the safety factor of the material used for the jacket.

2. The method for determining the ultimate bearing capacity of an offshore jacket-type platform according to claim 1, characterized in that: Based on the real-time monitoring of the ocean weather station, obtain the wave height on the ocean surface near the offshore jacket platform to be measured, denoted as H, with the unit of m; obtain the wind speed above the jacket, denoted as V, with the unit of m / s; obtain the sea current velocity below the offshore jacket platform to be measured, denoted as U, with the unit of m / s; obtain the water temperature, denoted as T, with the unit of °C.

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 to the mass of concrete used in the structure of the jacket platform. The stiffness data includes the average elastic modulus and average Poisson's ratio of the steel and concrete used in the jacket platform. The specific logic for collecting strength data is: Obtain the total mass of concrete and the total mass of steel bars used in constructing the jacket platform, and generate the ratio of the mass of steel bars to the mass of concrete used in the structure of the jacket platform. The formula used is: Among them, ρ is the strength data of the jacket-type platform, M g is the total mass of steel bars used in the jacket-type platform, M h is the total mass of concrete used in the jacket-type platform; The specific logic for collecting the stiffness data of the jacket platform is: where σ is the average elastic modulus of the steel and concrete used in the jacket-type platform, EM g is the average elastic modulus of the types of steel used in the jacket-type platform, EM h is the average elastic modulus of the types of concrete used in the jacket-type platform; Among them, τ is the average Poisson's ratio of the steel and concrete used in the jacket-type platform, PR g is the average Poisson's ratio of the steel types used in the jacket-type platform, PR h is the average Poisson's ratio of the concrete types used in the jacket-type platform; The specific logic for collecting the yield strength of the jacket is: Determine the material used for the jacket, and fabricate a tensile specimen according to the standard. Clamp the specimen on both sides of a hydraulic testing machine, slowly apply a tensile force, and record the corresponding strain. Calculate the stress using the following formula: where ε is the stress, F is the 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, and record the stress value at this time, denoted as ε y , ε y which is the yield strength of the jacket The specific logic for collecting the ultimate strength of the jacket is: On the basis of the yield strength test, continue to apply a tensile force until the specimen fractures, and record the maximum stress value at the moment of fracture. where 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; Obtain all the static loads borne by the jacket through the design drawings, including self-weight, equipment, pipelines, and accumulated water. Add up all the static loads to get the total static load of the jacket, denoted as F static ; The dynamic load refers to the instantaneous variable load caused by waves and wind speed. Use sensors to monitor the dynamic load borne by the jacket in real time, denoted as F dynamic .

4. The method for determining the ultimate bearing capacity of an offshore jacket-type platform according to claim 3, wherein: 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, U is the ocean current speed, is an exponential growth function representing the impact of water temperature on the environment. (T - 25) represents the difference between the current temperature and the ideal water temperature of 25 degrees Celsius. γ and ω are preset proportionality coefficients, and γ > ω > 0. C1 is the first constant correction exponent; The formula for generating the material impact index is: Among them, MAT is the material influence index, ρ is the strength data of the jacket-type platform, σ is the average elastic modulus of the steel and concrete used in the jacket-type platform, τ is the average Poisson's ratio of the steel and concrete used in the jacket-type platform, and ε u is the ultimate strength of the jacket, α and β are preset proportionality coefficients, and β > α > 0, and C2 is the second constant correction index; The formula for generating the load index is: LOA = μ * (F static + F dynamic ) Among them, LOA is the load index, F static is the static load, F dynamic is the dynamic load, and μ is a preset proportionality coefficient.

5. The method for determining the ultimate bearing capacity of an offshore jacket-type platform according to claim 4, characterized in that: The specific method for integrating the environmental impact index, material impact index, and load index and conducting a correlation analysis to obtain the bearing capacity evaluation index of the integrated offshore jacket platform is as follows: Among them, QS is the bearing capacity evaluation index, ENV is the environmental impact index, b is its preset proportionality coefficient, MAT is the material impact index, a is its preset proportionality coefficient, LOA is the load index, c is its preset proportionality 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-type 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 measured, QS is the bearing capacity evaluation index of the offshore jacket platform to be measured, 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-type platform, characterized in that: The system for determining the ultimate bearing capacity of an offshore jacket platform is used to execute the method for determining the ultimate bearing capacity of an offshore jacket platform according to any one of claims 1-6, and includes: A data acquisition module, configured to collect environmental parameters, structural parameters, and load parameters of the offshore jacket platform by prospecting, measuring, and analyzing the site. The environmental parameters are wave height, sea current velocity, wind speed, and temperature, the structural parameters are strength data, stiffness data, yield strength, and ultimate strength, and the load parameters are static load and dynamic load; A data analysis module, which generates an environmental impact index of the offshore jacket platform based on the dimensionless wave height, sea current velocity, wind speed, and temperature, generates a material impact index of the offshore jacket platform based on the dimensionless strength data, stiffness data, yield strength, and ultimate strength, and generates a load index of the offshore jacket platform based on the dimensionless static load and dynamic load; An index fusion module, configured to fuse the environmental impact index, the material impact index, and the load index, perform a correlation analysis, and obtain the bearing capacity evaluation index of the fused offshore jacket platform; An ultimate bearing capacity determination module, which determines the ultimate bearing capacity of the offshore jacket platform according to the bearing capacity evaluation index of the fused offshore jacket platform and the safety factor of the material used for the jacket.

Images