Safety cost benefit analysis model and method for offshore wind power reinforced concrete material

Abstract

The invention relates to a safety cost benefit analysis model and method for an offshore wind power reinforced concrete material. The model comprises a material parameterization module, a wave load calculation module, a safety check module, a cost analysis module and a dynamic visualization module. The method comprises the following steps: inputting environmental parameters, calculating a maximum wave bending moment at a designed wave height: calculating actual stress generated at the designed wave height according to the maximum wave bending moment, performing safety check on tensile strength, compressive strength and fatigue damage strength allowed by each material, and generating a comprehensive safety score; calculating the full life cycle cost of each material, and generating a comprehensive performance score through normalization of the mechanical properties and the cost of each material; and outputting a visual analysis report, and establishing a plane bubble graph by taking the total cost as an X axis and the comprehensive performance score as a Y axis. According to the method, the problems that a traditional analysis method is complex in calculation and single in evaluation dimension are solved, and the efficiency and reliability of floating type wind power basic material model selection can be remarkably improved.

Description

Technical Field

[0001] The present invention relates to the field of marine engineering technology, and in particular to a safety cost-benefit analysis model and method for offshore wind power steel-concrete materials. Background Art

[0002] Currently, offshore floating wind turbine foundations mostly utilize pure steel structures, but the use of steel-concrete structures is gradually increasing. For example, some new designs utilize steel-concrete hybrid structures. By using concrete in areas such as the buoys, heave plates, and horizontal coupling beams, combining the high strength of steel with the high stiffness of concrete, they optimize structural performance. With the improvement of material performance and the refinement of design specifications, steel-concrete structures are expected to become a key development direction for floating wind turbine foundations.

[0003] However, the current steel-concrete material selection method has the following defects: it is highly dependent on experience and historical engineering data, making it difficult to quantify the performance of new materials; the analysis dimension is single and the relationship between wave dynamic loads and material fatigue properties is not comprehensively considered; there is insufficient decision support and a lack of visualization tools, making it impossible to intuitively compare the cost-performance balance relationship.

[0004] Therefore, there is an urgent need for a multi-dimensional safety cost-benefit analysis model and method for floating wind power steel-concrete materials, which can be applied to support cost-benefit decision making in the structural design stage. Summary of the Invention

[0005] In view of the shortcomings of the existing technology, the present invention provides a safety cost-benefit analysis model and method for offshore wind power steel-concrete materials to solve the above problems.

[0006] The present invention provides the following technical solutions:

[0007] A safety cost-benefit analysis model for offshore wind power steel-concrete materials, including a material parameterization module, a wave load calculation module, a safety verification module, a cost analysis module, and a dynamic visualization module;

[0008] The material parameterization module is used to store data including mechanical property parameters and cost parameters of each material;

[0009] The wave load calculation module is used to calculate the maximum wave bending moment under the design wave height and provide actual stress for the safety verification module;

[0010] The safety verification module is used to verify whether the tensile strength, compressive strength and fatigue damage of each material meet the requirements of actual stress generation, and to express the safety mechanical performance index of the material through a comprehensive safety score;

[0011] The cost analysis module performs normalized processing on the data stored in the material parameterization module to perform a normalized material comprehensive performance score on the mechanical properties and costs of each material;

[0012] The dynamic visualization module generates a visual bubble chart based on the analysis results of the cost analysis module, with the total cost of the material over its entire life cycle as the X-axis and the material comprehensive performance score as the Y-axis.

[0013] Furthermore, the mechanical property parameters of each material include allowable compressive strength and tensile strength; and the cost parameters include original material cost, construction cost and maintenance cost.

[0014] Furthermore, the comprehensive safety score in the safety verification module includes a weighted score of compression safety, tensile safety and fatigue safety.

[0015] Furthermore, the cost analysis module also includes calculating a cost performance index, which is the ratio of the comprehensive performance score of the material to the total cost of the material over its entire life cycle.

[0016] Furthermore, the bubble size of the bubble chart reflects the safety score mechanical performance index, and different colors distinguish the safety verification status.

[0017] The present invention also includes a safety cost-benefit analysis method for offshore wind power steel-concrete materials, which adopts a selection analysis model for floating offshore wind power foundation materials of any of the above solutions, including the following steps:

[0018] Step S1: Input environmental parameters and calculate the maximum wave bending moment under the design wave height:

[0019] Step S2: Calculate the actual stress generated under the design wave height based on the maximum wave bending moment, perform safety checks on the allowable tensile, compressive, and fatigue damage strengths of each material, and generate a comprehensive safety score:

[0020] Step S3, calculating the total life cycle cost of each material, and generating a comprehensive performance score by normalizing the mechanical properties and costs of each material;

[0021] Step S4: Output a visual analysis report, and create a flat bubble chart with the total life cycle cost as the X-axis and the comprehensive performance score as the Y-axis.

[0022] Furthermore, the environmental parameters include wave height, wave period, float diameter, water depth and float height.

[0023] Furthermore, the comprehensive safety score includes a weighted score of compression safety, tensile safety and fatigue safety.

[0024] Furthermore, step S3 also includes calculating a cost-effectiveness index, which is the ratio of the comprehensive performance score of the material to the total cost of the material over its entire life cycle.

[0025] Furthermore, the size of the bubbles in the bubble chart reflects the comprehensive safety score: the larger the bubble, the higher the comprehensive safety score; different colors are used to distinguish the safety verification status: red indicates that the verification failed, green indicates that the verification passed, and orange indicates that the verification was partially passed.

[0026] The present invention has the following beneficial technical effects:

[0027] The present invention establishes a simplified calculation model for wave loads based on diffraction theory, uses an empirical formula to quickly estimate the diffraction coefficient, and combines it with first-order wave force theory to derive actual stress. Compared with the historical engineering data used in traditional methods, the verification results of the mechanical properties of the material are more accurate.

[0028] The mechanical properties of the present invention also involve fatigue characteristics. The normalization between mechanical properties and costs allows the entire model to be analyzed from multi-dimensional data, avoiding the defect of a single analysis dimension. The present invention also intuitively displays the relationship between material cost and performance by establishing a visual bubble chart, realizing two-dimensional mapping and interactive display of the material performance-cost relationship. The present invention solves the problems of complex calculations and single evaluation dimensions of traditional analysis methods, and can significantly improve the efficiency and reliability of basic material selection for floating offshore wind power. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 This is a flow chart of a safety cost-benefit analysis method for offshore wind power steel-concrete materials according to the present invention;

[0030] Figure 2 It is a bubble chart of a safety cost-benefit analysis model of offshore wind power steel-concrete materials according to the present invention. DETAILED DESCRIPTION

[0031] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0032] Example

[0033] The present invention discloses a safety cost-benefit analysis model for offshore wind power steel-concrete materials, specifically a floating wind power foundation, which includes a material parameterization module, a wave load calculation module, a safety verification module, a cost analysis module and a dynamic visualization module.

[0034] In this embodiment, the material parameterization module is used to store data including mechanical property parameters and cost parameters of each material; specifically, the materials may include pure steel structure, RC ordinary concrete, RC-ECC, RC-PVA, RC-UHPC, RC-FRP-UHPC, PVA fiber concrete, UHPC, etc.

[0035] The wave load calculation module is used to calculate the maximum wave bending moment under the design wave height and provide actual stress for the safety verification module; the safety verification module is used to verify whether the tensile, compressive and fatigue damage of each material meet the requirements of actual stress generation, and express the safety mechanical performance index of the material through a comprehensive safety score; the cost analysis module performs data standardization processing stored in the material parameterization module, including calculating the total material cost and mechanical performance score of the material over its entire life cycle, and performing a material comprehensive performance score normalized for the mechanical properties and costs of each material; the dynamic visualization module generates a visual bubble chart based on the analysis results of the cost analysis module, with the total cost of the material over its entire life cycle as the X-axis and the comprehensive material performance score as the Y-axis.

[0036] In this embodiment, the mechanical property parameters of each material include the allowable compressive strength and tensile strength; the cost parameters include the original material cost, construction cost and maintenance cost; the material parameterization module also stores the density of each material, material life, SN curve slope, wall thickness, etc.

[0037] The comprehensive safety score in the safety verification module includes a weighted score of compressive safety, tensile safety and fatigue safety; the cost analysis module also includes the calculation of a cost-effectiveness index, which is the ratio of the comprehensive performance score of the material to the total cost of the material over its entire life cycle; the bubble size of the bubble chart reflects the mechanical performance index of the safety score, and different colors distinguish the safety verification status.

[0038] See also Figure 1 The present invention also discloses a method for selecting and analyzing floating offshore wind power foundation materials, which adopts a safety cost-benefit analysis model of offshore wind power steel-concrete materials according to any of the aforementioned technical solutions; the method comprises the following steps:

[0039] Step S1: Input environmental parameters, including wave height H (m), wave period T (s), float diameter D (m), water depth h (m) and float height H (m). structure (m) Five parameters; basic wave parameters are calculated by the following formula:

[0040]

[0041] Where L is the wavelength, k is the wave number, and g is the acceleration due to gravity.

[0042] The diffraction effect is accurately calculated using the following Bessel function:

[0043] dimensionless wave number

[0044] First-order Bessel function of the first kind J1(ka)

[0045] Derivative term

[0046] Complex diffraction coefficient

[0047] Where a is the radius of the floating body, ka reflects the relative ratio of the structure size (radius) to the wave characteristics (wavelength); J0(ka) and J2(ka) are the first-order zero-order and second-order Bessel functions, respectively;

[0048] Calculate the wave force resultant:

[0049] Incident wave force

[0050] Diffraction wave force

[0051] Total wave force F total =|F incident +F diffraction |(Vector Overlay)

[0052] Calculation of maximum bending moment:

[0053] Maximum bending moment

[0054] Through the above steps, the maximum bending moment M of the design wave height can be achieved max Calculation.

[0055] Step S2: Calculate the actual tensile stress σ generated by the design wave height of each material actual :

[0056]

[0057] Where: D: float diameter (m); section moment of inertia I: t is the wall thickness of the floating foundation corresponding to each material.

[0058] Verification of tensile strength:

[0059] σ tensile allowable =σ actual ×γ t ;

[0060] Verification conditions: σ Tmaterial >σ tensile allowable ;

[0061] Among them, σTmaterial : Material tensile strength (MPa);

[0062] σ tensileallowable : Allowable tensile strength of the material (MPa);

[0063] γ t : Tensile safety factor, γ t =1.5.

[0064] Verification of compressive strength:

[0065] σ compressiveallowable =σ compressiveactual ×γ c ;

[0066] σ compressiveactual =σ actual ×0.6;

[0067] Verification conditions: σ Cmaterial >σ compressiveallowable ;

[0068] Where: Cmaterial : Material compressive strength (MPa);

[0069] γ c : compressive safety factor, γ c =1.2;

[0070] Actual compressive stress σ compressiveactual : In this embodiment, it is assumed that the compressive stress is 60% of the actual stress generated by the design wave height (empirical coefficient);

[0071] Fatigue damage assessment:

[0072]

[0073] Verification conditions: D fatigue <0.1

[0074] Among them, stress amplitude (Pa) σ amp =0.7×σ actual ×10 6 ;

[0075] σ f : material fatigue strength (Pa);

[0076] m: SN curve slope (SN_slope);

[0077] n i : The number of stress cycles in the i-th order, n i =10 8 ;

[0078] D fatigue: Fatigue damage accumulation;

[0079] Comprehensive safety score:

[0080] Tensile safety factor:

[0081] Among them, σ Tmaterial : Material tensile strength (MPa);

[0082] σ tensileallowable : Allowable tensile strength of the material (MPa);

[0083] Compressive safety factor:

[0084]

[0085] Among them, σ Cmaterial : Material compressive strength (MPa);

[0086] σ conpressiveactual : Allowable compressive strength of the material (MPa);

[0087] Fatigue safety factor:

[0088]

[0089] Among them, the safety factor Sfatigue is defined as the inverse of the maximum fatigue damage value;

[0090] When Dfatigue = 1, the safety factor Sfatigue = 1, indicating that the material has just reached the critical point of failure;

[0091] If Dfatigue < 1, then Sfatigue > 1, indicating that there is still a safety margin;

[0092] If Dfatigue>1, then Sfatigue<1, indicating that failure has occurred;

[0093] In this embodiment, the following formula is used:

[0094]

[0095] In the original formula, a lower limit threshold of 0.001 is added to the denominator D. This is to prevent the safety factor from being infinite when D = 0 (e.g., when no damage occurs) and to prevent the safety factor from being too large when D is too small (e.g., when D = 0.0001, S = 10,000), which would result in an unstable value.

[0096] Comprehensive safety score S S :

[0097] S S =(α*Stensile +β*S compressive +γ*S fatigue )*100

[0098] Among them: tensile safety factor α: (reflects the impact of tensile strength on overall safety), preferably,

[0099] α = 40%;

[0100] Compressive safety factor β: (reflects the impact of compressive strength on overall safety), preferably, β = 30%;

[0101] Fatigue safety factor γ: (reflects the impact of fatigue life on overall safety), preferably, γ = 30%;

[0102] The weights are added up to: α+β+γ=1, and the score is converted to a percentage system (×100). The higher the value, the better the material safety.

[0103] Step S3, material cost analysis:

[0104] The total material cost C over the entire life cycle of the material is calculated using the following formula total ;

[0105]

[0106]

[0107] Where ρ is the density of each material, V is the volume of the material (calculated by inputting the displacement value), displacement is the input displacement value, T1 is the design life of each material, C m 、C t 、C mt They are unit material cost, construction cost, and maintenance cost respectively.

[0108] Normalized cost-performance ratio score for mechanical properties and cost:

[0109] Calculate the mechanical performance score S mech :

[0110]

[0111] Where μ and η are adjustable weight coefficients, satisfying μ+η=1. σ c , σ t are the compressive and tensile strength of the material, σ cmax and σ tmax are the maximum compressive and tensile values ​​of each material in the library.

[0112] Calculate cost score S C :

[0113]

[0114] Among them, ε, κ, is an adjustable weight coefficient, satisfying that the sum of the three is 1, preferably, ε, κ, They are 0.5, 0.3 and 0.2 respectively. mt , σ f are design life, material maintenance cost, fatigue strength, T max 、C mtmax , σ f,max It is the maximum value among the life cycle, maintenance cost and fatigue strength values ​​of each material.

[0115] Calculate the material comprehensive performance score Y:

[0116] Y=τ·S mech +υ·S C

[0117] Among them, τ, υ are adjustable weight coefficients, satisfying τ + υ = 1;

[0118] In this embodiment, optionally,

[0119]

[0120] Furthermore, the cost-performance index (MRP) can be calculated to score the cost-performance of materials:

[0121]

[0122] Among them, the larger the value of the cost-effectiveness index MRP is, the higher the cost-effectiveness of the material is.

[0123] Step S5, generate a visual bubble chart:

[0124] Among them, such as Figure 2 As shown, the total cost C total A plane bubble chart is established with X as the X-axis and the comprehensive performance score Y as the Y-axis, wherein the size of the bubble reflects the comprehensive safety score coefficient, and the larger the bubble, the higher the comprehensive safety score; different colors distinguish the safety verification status, red indicates that the verification has failed, green indicates that the verification has passed, and orange indicates that the verification has partially passed; the present invention displays a fast nested process from input parameters to results, and the chart will change in real time with the change of input parameters, reflecting dynamic visualization.

[0125] The present invention solves the problems of complex calculations and single evaluation dimensions in traditional analysis methods, and can significantly improve the efficiency and reliability of floating foundation material selection.

[0126] The above-described embodiments merely represent specific implementations of the present invention. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that a person skilled in the art would be able to make numerous variations and improvements without departing from the spirit of the present invention, and all such variations and improvements fall within the scope of protection of the present invention.

Claims

1. A safety cost-benefit analysis model for offshore wind power steel-concrete materials, characterized by: It includes material parameterization module, wave load calculation module, safety verification module, cost analysis module and dynamic visualization module; The material parameterization module is used to store data including mechanical property parameters and cost parameters of each material; The wave load calculation module is used to calculate the maximum wave bending moment under the design wave height and provide actual stress for the safety verification module; The safety verification module is used to verify whether the tensile strength, compressive strength and fatigue damage of each material meet the requirements of actual stress generation, and to express the safety mechanical performance index of the material through a comprehensive safety score; The cost analysis module performs normalized processing on the data stored in the material parameterization module to perform a normalized material comprehensive performance score on the mechanical properties and costs of each material; The dynamic visualization module generates a visual bubble chart based on the analysis results of the cost analysis module, with the total cost of the material over its entire life cycle as the X-axis and the material comprehensive performance score as the Y-axis.

2. A selection analysis model for floating offshore wind power foundation materials according to claim 1, characterized in that: The mechanical property parameters of each material include allowable compressive strength and tensile strength; the cost parameters include original material cost, construction cost and maintenance cost.

3. The selection analysis model of floating offshore wind power foundation materials according to claim 1, characterized in that: The comprehensive safety score in the safety verification module includes a weighted score of compression safety, tensile safety and fatigue safety.

4. The selection and analysis model for floating offshore wind power foundation materials according to claim 1, characterized in that: The cost analysis module also includes calculating a cost performance index, which is the ratio of the comprehensive performance score of the material to the total cost of the material over its entire life cycle.

5. The selection analysis model for floating offshore wind power foundation materials according to claim 1, characterized in that: The bubble size of the bubble chart reflects the safety score mechanical performance index, and different colors distinguish the safety verification status.

6. A safety cost-benefit analysis method for offshore wind power steel-concrete materials, using a selection analysis model for floating offshore wind power foundation materials according to any one of claims 1 to 5, comprising the following steps: Step S1: Input environmental parameters and calculate the maximum wave bending moment under the design wave height: Step S2: Calculate the actual stress generated under the design wave height based on the maximum wave bending moment, perform safety checks on the allowable tensile, compressive, and fatigue damage strengths of each material, and generate a comprehensive safety score: Step S3, calculating the total life cycle cost of each material, and generating a comprehensive performance score by normalizing the mechanical properties and costs of each material; Step S4: Output a visual analysis report, and create a flat bubble chart with the total life cycle cost as the X-axis and the comprehensive performance score as the Y-axis.

7. A safety cost-benefit analysis method for offshore wind power steel-concrete materials according to claim 6, wherein the environmental parameters include wave height, wave period, float diameter, water depth and float height.

8. A safety cost-benefit analysis method for offshore wind power steel-concrete materials according to claim 6, wherein the comprehensive safety score includes a weighted score of compressive safety, tensile safety, and fatigue safety.

9. The safety cost-benefit analysis method for offshore wind power steel-concrete materials according to claim 6, wherein step S3 further comprises calculating a cost-effectiveness index, wherein the cost-effectiveness index is a ratio of the comprehensive performance score of the material to the total cost of the material over its entire life cycle.

10. A safety cost-benefit analysis method for offshore wind power steel-concrete materials according to claim 6, wherein the size of the bubbles in the bubble chart reflects the comprehensive safety score: the larger the bubble, the higher the comprehensive safety score; different colors are used to distinguish the safety verification status.

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