Offshore wind power five-connected-cylinder foundation anti-overturning ultimate bearing capacity calculation method

Abstract

The invention discloses an offshore wind power five-connected-cylinder foundation anti-overturning ultimate bearing capacity calculation method which comprises the following steps: S1, according to a five-connected-cylinder foundation anti-overturning bearing equivalent schematic diagram, enabling a five-connected-cylinder foundation to be equivalent to a plurality of foundations with regular shapes; s2, a five-connected-cylinder foundation overturning damage mode is provided, and the position of a five-connected-cylinder foundation rotating shaft is determined; s3, according to the overturning failure mode of the five-connected-cylinder foundation, the components of the resistance moment of the five-connected-cylinder foundation under the overturning load effect are determined, and the components comprise the resistance moment Ma and p generated by a wedge failure area, the resistance moment Mf generated by an arc failure area and the resistance moment Ms generated by shear force between a sliding failure area and soil bodies in an adjacent non-sliding area; s4, according to the moment balance principle, the ultimate anti-overturning bearing capacity of the five-connected-cylinder foundation is obtained; and S5, correcting the ultimate anti-overturning bearing capacity, obtained in the step S4, of the five-connected-cylinder foundation by considering the influence of the eccentricity of the rotating shaft on the resistance moment Mf generated by the arc-shaped damage area.

Description

Technical Field

[0001] The present invention relates to the field of offshore engineering infrastructure, and particularly applies to a theoretical calculation method for the anti-overturning ultimate bearing capacity of a five-barrel foundation for offshore wind power in clay. Background Art

[0002] As a new type of fixed foundation applied in deep and far seas, the five-barrel foundation is connected by four arc-shaped plates and four independent single-barrel foundations (side barrels). The arc-shaped plates, the skirt plates of the side barrels, and the welded top plate together enclose a middle barrel, thus forming an integral structure, namely the five-barrel foundation. By changing the large-diameter single barrel into small-diameter multi-barrels, this foundation type effectively avoids the thin-plate stability problem caused by the over-large skirt plate size of the single-barrel foundation, and significantly improves the buckling resistance of the skirt plate. The middle barrel and the side barrels of the five-barrel foundation are connected as a whole, having good floating stability, which is conducive to integral floating transportation and installation. The above excellent properties of the five-barrel foundation make this foundation have great development prospects in the field of offshore wind power engineering.

[0003] As an offshore wind power is a high-rise structure, the wind turbine will bear huge wind loads during its service life. Especially under extreme conditions, the overturning force transmitted to the lower foundation through the upper structure is extremely large. Therefore, the overturning load is the most main and dangerous load form borne by the offshore wind power foundation, which is directly related to the safety and stability of the overall structure. However, at present, the failure mode and bearing capacity calculation method of the five-barrel foundation under the action of the overturning load have not been clearly proposed. The existing bearing capacity specifications and theoretical calculation methods of the single-barrel foundation cannot be directly applied to the five-barrel foundation. The calculation of the ultimate bearing capacity of the five-barrel foundation mainly relies on the finite element method, and the finite element modeling process is cumbersome and the calculation process takes a long time. Therefore, there is an urgent need for a method that can accurately and efficiently calculate the anti-overturning ultimate bearing capacity of the five-barrel foundation. Summary of the Invention

[0004] The purpose of the present invention is to overcome the deficiencies in the prior art and provide a calculation method for the anti-overturning ultimate bearing capacity of a five-barrel foundation for offshore wind power, so as to provide a theoretical support for the evaluation of the anti-overturning bearing performance of the five-barrel foundation in engineering.

[0005] The purpose of the present invention is achieved through the following technical solutions:

[0006] A calculation method for the anti-overturning ultimate bearing capacity of a five-barrel foundation for offshore wind power includes the following steps:

[0007] S1. According to the anti-overturning bearing equivalent schematic diagram of the five-barrel foundation, the five-barrel foundation is equivalent to a number of foundations with regular shapes;

[0008] S2. Propose the overturning failure mode of the five-barrel foundation and determine the position of the rotation axis of the five-barrel foundation;

[0009] S3. Determine the components of the resistance moment of the five - connected cylinder foundation under the action of the overturning load according to the overturning failure mode of the five - connected cylinder foundation, including the resistance moment \(M\) generated in the wedge - failure area a,p , the resistance moment \(M\) generated in the circular - arc failure area f and the resistance moment \(M\) generated by the shear force between the sliding - failure area and the adjacent non - sliding area of the soil mass s in three parts;

[0010] S4. Obtain the ultimate anti - overturning bearing capacity of the five - connected cylinder foundation according to the principle of moment balance;

[0011] S5. Consider the influence of the eccentricity of the rotation axis on the resistance moment \(M\) f generated in the circular - arc failure area, and correct the ultimate anti - overturning bearing capacity of the five - connected cylinder foundation obtained in step S4.

[0012] Further, it is applicable to different working conditions, including the opposite - side loading condition in homogeneous clay, the diagonal loading condition in homogeneous clay, the opposite - side loading condition in normally consolidated clay, and the diagonal loading condition in normally consolidated clay;

[0013] Among them, the opposite - side loading condition and the diagonal loading condition are distinguished according to the angle of the overturning load acting on the five - connected cylinder foundation. The opposite - side loading condition is that the overturning moment is loaded in the \(0^{\circ}\) direction, and the diagonal loading condition is that the overturning moment is loaded in the \(45^{\circ}\) direction;

[0014] Homogeneous clay and normally consolidated clay are distinguished according to the distribution law of the undrained shear strength \(s\) u of the soil mass along the depth direction of the soil mass. Homogeneous clay means that the undrained shear strength \(s\) u is uniformly distributed along the depth direction of the soil mass, and normally consolidated clay means that the undrained shear strength \(s\) u is linearly distributed along the depth direction of the soil mass.

[0015] Further, for the opposite - side loading condition in homogeneous clay:

[0016] In step S1, according to the equivalent schematic diagram of the anti - overturning bearing of the five - connected cylinder foundation, the five - connected cylinder foundation is equivalent to a type - I foundation and two type - II foundations. \(B\) i is the length of the equivalent foundation, \(i = I, II\), and the values are calculated according to the following formula:

[0017]

[0018] Among them, \(D\) is the opposite - side length of the five - connected cylinder foundation; \(D1\) is the diameter of the middle cylinder of the five - connected cylinder foundation; \(D2\) is the diameter of the side cylinder of the five - connected cylinder foundation; \(\omega\) is an intermediate variable in the solution process; \(\alpha\) is a geometric parameter. The value - taking methods of several key geometric parameters are given below:

[0019]

[0020] In step S2, a five-barrel foundation overturning failure mode is proposed, and the position of the rotation axis of the five-barrel foundation is determined as:

[0021]

[0022] where z M is the height of the rotation axis, and L is the height of the five-barrel foundation;

[0023] In step S3, the resistance moment M p produced by the passive zone of the wedge only exists when z M > 0.5L, and specifically is:

[0024]

[0025] where E p is the unit earth pressure exerted by the soil in the passive zone of the wedge on each equivalent foundation; N p is the passive earth pressure coefficient, μ is the friction coefficient between the sliding wedge and the foundation; γ' is the unit weight of the soil; z w is the height of the wedge; z p is the distance from the acting point of the earth pressure E p to the bottom of the passive zone of the wedge;

[0026] The resistance moment M f produced by the circular failure zone is:

[0027]

[0028] where R M is the radius of the circular slip surface, and α M , β M , β' M , θ M are geometric parameters in the failure mode diagram of the five-barrel foundation under the overturning load, and satisfy the following relationship:

[0029]

[0030] The resistance moment M s produced by the shear force between the sliding failure zone and the adjacent non-sliding zone soil includes two parts: one part is the resistance moment M s1 produced by the shear force between the sliding surfaces on both sides of the wedge and the adjacent non-sliding zone soil; the other part is the resistance moment M s2 produced by the shear force between the rotational slip surface of the soil in the middle of the adjacent side barrel and the non-sliding zone soil;

[0031] The resistance moment M s1 only exists when zM Exists when it is > 0.5L, and is:

[0032]

[0033] Among them,

[0034] The resisting moment M s2 Is:

[0035]

[0036] Among them, R Ms Is the radius of the torsional shear plane; D3 is the distance between the centers of two adjacent side cylinders, that is, B i = D3 = D - D2; ρ is an intermediate variable in the solution process;

[0037] The resisting moment M generated by the shear force between the sliding failure zone and the soil body in the adjacent non-sliding zone s Is:

[0038] M s = 2M s1 + 2M s2

[0039] In step S4, according to the principle of moment balance, the ultimate anti-overturning bearing capacity of the five-cylinder foundation is:

[0040] M = M p + M f + M s

[0041] In step S5, considering the influence of the eccentricity of the rotation axis, the corrected ultimate anti-overturning bearing capacity of the five-cylinder foundation is:

[0042] M cor = M p + ξM f + M s

[0043] Among them, ξ is the correction coefficient. For the opposite-side loading condition in homogeneous clay, ξ = 0.85 - 0.95. For the five-cylinder foundation with a relatively small length-diameter ratio, ξ takes the smaller value within the range; for the five-cylinder foundation with a relatively large length-diameter ratio, ξ takes the larger value within the range.

[0044] Furthermore, for the diagonal loading condition in homogeneous clay:

[0045] In step S1, according to the anti-overturning bearing capacity equivalent schematic diagram of the five-cylinder foundation, the five-cylinder foundation is equivalent to one type-I foundation, two type-II foundations, and two type-III foundations; B i Is the length of the equivalent foundation, i = I, II, III, and the calculation and value-taking are carried out according to the following formula:

[0046]

[0047] Among them, D’ is the diagonal length of the five-connected cylinder foundation, and D2 is the diameter of the side cylinder of the five-connected cylinder foundation. ω is an intermediate variable in the solution process;

[0048] In step S2, the position of the rotation axis of the five-connected cylinder foundation is the same as:

[0049]

[0050] Among them, z M is the height of the rotation axis, and L is the height of the five-connected cylinder foundation;

[0051] In step S3, the resistance moment M generated in the passive zone of the wedge p only exists when z s M > 0.5L, and specifically is:

[0052]

[0053] Among them, E p is the unit earth pressure generated by the soil in the passive zone of the wedge on each equivalent foundation; N p is the passive earth pressure coefficient, μ is the friction coefficient between the sliding wedge and the foundation; γ’ is the unit weight of the soil; z w is the height of the wedge; z p is the distance from the acting point of the earth pressure E p to the bottom of the passive zone of the wedge;

[0054] The resistance moment M generated by the shear force between the circular failure zone and the soil in the adjacent non-sliding zone f is: [[ID=Y]]

[0055]

[0056] Among them, R M is the radius of the circular sliding surface, and α M , β M , β’ M are the geometric parameters in the failure mode diagram of the five-connected cylinder foundation under the action of the overturning load, and satisfy the following relationship:

[0057]

[0058] The resistance moment M generated by the shear force between the sliding failure zone and the soil in the adjacent non-sliding zone s only exists when z M > 0.5L, and specifically is:

[0059]

[0060] Among them,

[0061] In step S4, according to the principle of moment balance, the ultimate anti-overturning bearing capacity of the five-connected cylinder foundation is:

[0062] M = M p + M f + M s

[0063] In step S5, considering the influence of the eccentricity of the rotation axis, the corrected ultimate anti-overturning bearing capacity of the five-connected cylinder foundation is:

[0064] M cor = M p + ξM f + M s

[0065] Among them, ξ is the correction coefficient. For the diagonal loading condition in homogeneous clay, ξ = 0.9 - 1.0. For the five-connected cylinder foundation with a relatively small length-diameter ratio, ξ takes the smaller value within the range; for the five-connected cylinder foundation with a relatively large length-diameter ratio, ξ takes the larger value within the range.

[0066] Furthermore, for the opposite-side loading condition in normally consolidated clay:

[0067] In step S1, according to the equivalent diagram of the anti-overturning bearing capacity of the five-connected cylinder foundation, the five-connected cylinder foundation is equivalent to a type I foundation and two type II foundations; B i is the length of the equivalent foundation, i = I, II, and the values are calculated according to the following formula:

[0068]

[0069] Among them, D is the opposite-side length of the five-connected cylinder foundation; D1 is the diameter of the middle cylinder of the five-connected cylinder foundation; D2 is the diameter of the side cylinder of the five-connected cylinder foundation; ω is the intermediate variable in the solution process; α is the geometric parameter. The following gives the value-taking methods of several key geometric parameters:

[0070]

[0071] In step S2, the overturning failure mode of the five-connected cylinder foundation is proposed, and the position of the rotation axis of the five-connected cylinder foundation is determined as:

[0072]

[0073] Among them, z M is the height of the rotation axis, and L is the height of the five-connected cylinder foundation;

[0074] In step 3, the resistance moment M a,p generated by the wedge failure zone only when z MExists when it is > 0.5L, specifically:

[0075]

[0076] Among them, E p is the unit earth pressure generated by the soil mass in the passive zone of the wedge on each equivalent foundation; N p is the coefficient of passive earth pressure, γ’ is the unit weight of the soil mass; z w is the height of the wedge; z p is the distance from the acting point of the earth pressure E p to the bottom of the passive zone of the wedge; E a is the unit earth pressure generated by the soil mass in the active zone of the wedge on each equivalent foundation; N a is the coefficient of active earth pressure, z a is the distance from the acting point of the unit earth pressure E a to the bottom of the active zone of the wedge; the undrained shear strength s of the soil mass u is taken as k·z w / 2, where k is the change gradient of the undrained shear strength of the soil mass;

[0077] The resisting moment M generated by the resistance force of the circular arc failure zone f is:

[0078]

[0079] Among them, R M is the radius of the circular arc sliding surface, α M , β M , β’ M , θ M are the geometric parameters in the failure mode diagram of the five - connected cylinder foundation under the action of the overturning load, and satisfy the following relationship:

[0080]

[0081] The undrained shear strength s of the soil mass uf1i , s uf2i is calculated and taken as follows:

[0082]

[0083] The resisting moment M generated by the shear force between the sliding failure zone and the adjacent non - sliding zone soil mass s includes two parts: one part is the resisting moment M s1 generated by the shear force between the sliding surfaces on both sides of the wedge and the adjacent non - sliding zone soil mass; the other part is the resisting moment M s2 generated by the shear force between the rotational sliding surface of the soil mass in the middle of the adjacent side cylinders and the non - sliding zone soil mass;

[0084] Resisting moment M s1 Exists only when z M > 0.5L, and is:

[0085]

[0086] Wherein, Undrained shear strength s of the soil mass u Take the value according to k·z w / 2;

[0087] Resisting moment M s2 Is:

[0088]

[0089] Wherein, R Ms Is the radius of the torsional shear plane; D3 is the distance between the centers of two adjacent side cylinders, that is, B i = D3 = D - D2; ρ is an intermediate variable in the solution process;

[0090] Undrained shear strength s of the soil mass usi Calculate and take the value according to the following formula:

[0091]

[0092] The resisting moment M generated by the shear force between the sliding failure zone and the soil mass in the adjacent non-sliding zone s Is:

[0093] M s = 4M s1 + 2M s2

[0094] In step S4, according to the principle of moment balance, the ultimate anti-overturning bearing capacity of the five-cylinder foundation is:

[0095] M = M a,p + M f + M s

[0096] In step S5, considering the influence of the eccentricity of the rotation axis, the corrected ultimate anti-overturning bearing capacity of the five-cylinder foundation is:

[0097] M cor = M a,p + ξM f + M s

[0098] Wherein, ξ is the correction coefficient. For the opposite-side loading condition in normally consolidated clay, ξ = 0.9 - 0.95. For the five-cylinder foundation with a relatively small aspect ratio, ξ takes the smaller value within the range; for the five-cylinder foundation with a relatively large aspect ratio, ξ takes the larger value within the range.

[0099] Furthermore, for the diagonal loading condition in normally consolidated clay:

[0100] In step S1, according to the anti-overturning bearing capacity equivalent schematic diagram of the five-connected cylinder foundation, the five-connected cylinder foundation is equivalent to one type-I foundation, two type-II foundations, and two type-III foundations; B i is the length of the equivalent foundation, i = I, II, III, and the values are calculated according to the following formula:

[0101]

[0102] where D’ is the diagonal length of the five-connected cylinder foundation, D2 is the diameter of the side cylinder of the five-connected cylinder foundation, ω is an intermediate variable in the solution process;

[0103] In step S2, the position of the rotation axis of the five-connected cylinder foundation is the same as:

[0104]

[0105] where z M is the height of the rotation axis, and L is the height of the five-connected cylinder foundation;

[0106] In step S3, the resistance moment M a,p exists only when z M > 0.5L, and specifically:

[0107]

[0108] where E p is the unit earth pressure generated by the soil in the passive zone of the wedge on each equivalent foundation; N p is the passive earth pressure coefficient, γ’ is the unit weight of the soil; z w is the height of the wedge; z p is the distance from the acting point of the earth pressure E p to the bottom of the passive zone of the wedge; E a is the unit earth pressure generated by the soil in the active zone of the wedge on each equivalent foundation; N a is the active earth pressure coefficient, z a is the distance from the acting point of the unit earth pressure E a to the bottom of the active zone of the wedge; the undrained shear strength s u is taken as k·z w / 2, and k is the change gradient of the undrained shear strength of the soil;

[0109] The resistance moment M f generated by the circular arc failure zone is:

[0110]

[0111] Among them, R M is the radius of the circular arc sliding surface, and α M , β M , β’ M are geometric parameters in the failure mode diagram of the five - connected cylinder foundation under the action of the overturning load, and satisfy the following relationships:

[0112]

[0113] The undrained shear strength s of the soil uf1i , s uf2i is calculated and taken according to the following formula:

[0114]

[0115] The resistance moment M generated by the shear force between the sliding failure zone and the adjacent non - sliding zone of the soil s exists only when z M > 0.5L, and is:

[0116]

[0117] Among them,

[0118] In step S4, according to the principle of moment balance, the ultimate anti - overturning bearing capacity of the five - connected cylinder foundation is:

[0119] M = M a,p + M f + M s

[0120] In step S5, considering the influence of the eccentricity of the rotation axis, the corrected ultimate anti - overturning bearing capacity of the five - connected cylinder foundation is:

[0121] M cor = M a,p + ξM f + M s

[0122] Among them, ξ is the correction coefficient. For the side - loading condition in normally consolidated clay, ξ = 0.95 - 1.0. For the five - connected cylinder foundation with a relatively small length - diameter ratio, ξ takes the smaller value within the range; for the five - connected cylinder foundation with a relatively large length - diameter ratio, ξ takes the larger value within the range.

[0123] The present invention also provides a device for calculating the ultimate anti - overturning bearing capacity of an offshore wind power five - connected cylinder foundation, including:

[0124] An equivalent unit, which is used to equivalent the five - connected cylinder foundation into several regularly - shaped foundations according to the equivalent schematic diagram of the anti - overturning bearing capacity of the five - connected cylinder foundation;

[0125] A mode setting unit for setting the overturning failure mode of the five - connected cylinder foundation and determining the position of the rotation axis of the five - connected cylinder foundation;

[0126] A resistance moment determination unit, according to the overturning failure mode of the five - connected cylinder foundation, determines the components of the resistance moment of the five - connected cylinder foundation under the action of the overturning load, including the resistance moment M a,p generated in the wedge - shaped failure zone, the resistance moment M f generated in the circular - arc failure zone, and the resistance moment M s generated by the shear force between the sliding failure zone and the adjacent non - sliding zone soil mass, which are three parts;

[0127] A calculation unit for obtaining the ultimate anti - overturning bearing capacity of the five - connected cylinder foundation according to the moment balance principle;

[0128] A correction unit for considering the influence of the eccentricity of the rotation axis on the resistance moment M f generated in the circular - arc failure zone and correcting the ultimate anti - overturning bearing capacity of the five - connected cylinder foundation.

[0129] The present invention also provides an electronic device, including a memory, a processor, and a computer program stored on the memory and executable on the processor. When the processor executes the program, the steps of the calculation method for the ultimate anti - overturning bearing capacity of the five - connected cylinder foundation for offshore wind power are realized.

[0130] The present invention also provides a computer - readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the steps of the calculation method for the ultimate anti - overturning bearing capacity of the five - connected cylinder foundation for offshore wind power are realized.

[0131] Compared with the prior art, the beneficial effects brought by the technical solution of the present invention are:

[0132] 1. Theoretical innovation and technology filling: Based on the moment balance principle, the present invention conducts a theoretical analysis on the failure mechanism and anti - overturning bearing capacity of the five - connected cylinder foundation during the anti - overturning process, and for the first time establishes a theoretical calculation method for the anti - overturning bearing capacity of the five - connected cylinder foundation, filling the blank in the prior art of the lack of corresponding theoretical calculation methods.

[0133] 2. Strong engineering applicability: The basic parameters and calculation theories adopted are all common and easily obtainable engineering data in the design of marine engineering foundations, ensuring the feasibility and wide applicability of this calculation method in practical applications, and facilitating engineers to quickly evaluate the bearing capacity during the design stage.

[0134] 3. Improve the reliability of calculation results: The influence of eccentricity of the foundation rotation axis under the action of overturning load is fully considered in the method, and a correction coefficient is introduced to correct the calculation results, so that the obtained anti-overturning bearing capacity is more in line with the actual engineering conditions, thus improving the accuracy and safety of the design calculation.

[0135] 4. Significantly improve the calculation efficiency: Compared with the traditional finite element analysis method, the theoretical calculation method of the present invention does not require cumbersome modeling and long-time numerical calculation, and can quickly obtain the evaluation results of the anti-overturning bearing capacity, greatly improving the work efficiency of engineering design and evaluation.

[0136] Generally speaking, the present invention not only innovatively calculates the anti-overturning ultimate bearing capacity of the five-connected cylinder foundation for offshore wind power theoretically, but also takes into account the engineering practicability and high efficiency, providing reliable and convenient technical support for related engineering designs. Brief Description of the Drawings

[0137] Figure 1 It is the equivalent diagram of the anti-overturning bearing of the five-connected cylinder foundation in homogeneous clay;

[0138] Figure 2 It is the overturning failure mode of the five-connected cylinder foundation in homogeneous clay;

[0139] Figure 3 It is the equivalent diagram of the anti-overturning bearing of the five-connected cylinder foundation in normally consolidated clay;

[0140] Figure 4 It is the overturning failure mode of the five-connected cylinder foundation in normally consolidated clay;

[0141] Figure 5 It is the semi-structural plan view of the five-connected cylinder foundation (opposite sides);

[0142] Figure 6 It is the semi-structural plan view of the five-connected cylinder foundation (diagonal). Detailed Embodiments

[0143] The present invention will be further described in detail below with reference to the drawings and specific embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0144] This embodiment provides a method for calculating the anti-overturning ultimate bearing capacity of a five-connected cylinder foundation for offshore wind power, including the following steps:

[0145] Step 1: According to the equivalent diagram of the anti-overturning bearing of the five-connected cylinder foundation, the five-connected cylinder foundation is equivalent to several foundations with regular shapes;

[0146] Step 2: Propose the overturning failure mode of the five-connected cylinder foundation and determine the position of the rotation axis of the five-connected cylinder foundation;

[0147] Step 3: According to the overturning failure mode of the five-connected cylinder foundation, determine the main components of the resistance moment of the foundation under the action of the overturning load, generally including the resistance moment M generated in the wedge failure area a,p , the resistance moment M generated in the circular arc failure area f and the resistance moment M generated by the shear force between the sliding failure area and the adjacent non-sliding area of the soil mass s , which are three parts in total

[0148] Step 4: According to the principle of moment balance, finally obtain the ultimate anti-overturning bearing capacity M of the five-connected cylinder foundation: M = M a,p + M f + M s .

[0149] Step 5: Considering the influence of the eccentricity of the rotation axis on the resistance moment M generated in the circular arc failure area f , correct the ultimate anti-overturning bearing capacity of the five-connected cylinder foundation obtained in Step 4: M cor = M a,p + ξM f + M s .

[0150] In the above calculation scheme, it is necessary to specifically analyze the ultimate anti-overturning bearing capacity of the five-connected cylinder foundation for different working conditions. Different working conditions mainly include four working conditions: the opposite-side loading condition in homogeneous clay, the diagonal loading condition in homogeneous clay, the opposite-side loading condition in normally consolidated clay, and the diagonal loading condition in normally consolidated clay; the opposite-side loading condition and the diagonal loading condition are distinguished according to the angle at which the overturning load acts on the five-connected cylinder foundation. The opposite-side loading condition is that the overturning moment is loaded in the 0° direction, and the diagonal loading condition is that the overturning moment is loaded in the 45° direction; homogeneous clay and normally consolidated clay are distinguished according to the distribution law of the undrained shear strength s u of the soil mass along the depth direction of the soil mass. Homogeneous clay means that the undrained shear strength s u of the soil mass is evenly distributed along the depth direction of the soil mass, and normally consolidated clay means that the undrained shear strength s u of the soil mass is linearly distributed along the depth direction of the soil mass

[0151] The following is an explanation according to the above four working conditions respectively

[0152] (1) Opposite-side loading condition in homogeneous clay

[0153] In Step 1, according to the equivalent schematic diagram of the anti-overturning bearing of the five-connected cylinder foundation, the five-connected cylinder foundation is equivalent to a Type I foundation and two Type II foundations. B i is the length of the equivalent foundation, and i = I, II. The values can be calculated according to the following formula

[0154]

[0155] Among them, D is the opposite side length of the five-connected cylinder foundation; D1 is the diameter of the middle cylinder of the five-connected cylinder foundation; D2 is the diameter of the side cylinder of the five-connected cylinder foundation; ω is an intermediate variable in the solution process; α is a key geometric parameter. For the convenience of calculation, combined with the structural plan schematic diagram of the five-connected cylinder foundation under the opposite side loading condition, the value-taking method of the following key geometric parameters is further given:

[0156]

[0157] In step 2, the overturning failure mode of the five-connected cylinder foundation is proposed, and the position of the rotation axis of the five-connected cylinder foundation is determined as

[0158]

[0159] Among them, z M is the height of the rotation axis, and L is the height of the five-connected cylinder foundation.

[0160] In step 3, according to the overturning failure mode of the five-connected cylinder foundation, it is determined that the resistance moment of the foundation under the action of the overturning load is mainly provided by the resistance moment M p generated by the passive zone of the wedge, the resistance moment M f generated by the circular arc failure zone, and the resistance moment M s generated by the shear force between the sliding failure zone and the adjacent non-sliding zone soil body.

[0161] The resistance moment M p (only exists when z M > 0.5L) is:

[0162]

[0163] Among them, E p is the unit earth pressure generated by the soil body in the passive zone of the wedge on each equivalent foundation; N p is the passive earth pressure coefficient, μ is the friction coefficient between the sliding wedge and the foundation; γ’ is the unit weight of the soil body; z w is the height of the wedge; z p is the distance from the acting point of the earth pressure E p to the bottom of the passive zone of the wedge.

[0164] The resistance moment M f generated by the circular arc failure zone is:

[0165]

[0166] Among them, R M is the radius of the circular arc sliding surface, α M , βM , β’ M , θ M are the key geometric parameters in the failure mode diagram of the five - cylinder foundation under the overturning load, and satisfy the following relationship:

[0167]

[0168] The resistance moment M generated by the shear force between the sliding failure zone and the adjacent non - sliding zone soil mass s includes two parts: one part is the resistance moment M generated by the shear force between the sliding surfaces on both sides of the wedge and the adjacent non - sliding zone soil mass s1 ; the other part is the resistance moment M generated by the shear force between the rotational sliding surface of the soil mass in the middle of the adjacent side cylinders and the non - sliding zone soil mass s2 .

[0169] The resistance moment M s1 (only exists when z M > 0.5L) is:

[0170]

[0171] Wherein,

[0172] The resistance moment M s2 is:

[0173]

[0174] Wherein, R Ms is the radius of the torsional shear plane; D3 is the distance between the centers of two adjacent side cylinders, that is, B i = D3 = D - D2; ρ is an intermediate variable in the solution process.

[0175] The resistance moment M generated by the shear force between the sliding failure zone and the adjacent non - sliding zone soil mass s is:

[0176] M s = 2M s1 + 2M s2

[0177] In step 4, according to the moment balance principle, the ultimate anti - overturning bearing capacity of the five - cylinder foundation is:

[0178] M = M p + M f + M s

[0179] In step 5, considering the influence of the eccentricity of the rotation axis, the corrected ultimate anti - overturning bearing capacity of the five - cylinder foundation is:

[0180] M cor= M p + ξM f + M s

[0181] Among them, ξ is the correction coefficient. For the case of edge loading in homogeneous clay, ξ = 0.85 - 0.95. For the five-connected cylinder foundation with a relatively small aspect ratio, ξ takes the smaller value within the range; for the five-connected cylinder foundation with a relatively large aspect ratio, ξ takes the larger value within the range.

[0182] (2) Diagonal loading condition in homogeneous clay

[0183] In step 1, according to the equivalent diagram of the anti-overturning bearing capacity of the five-connected cylinder foundation, the five-connected cylinder foundation is equivalent to one type I foundation, two type II foundations, and two type III foundations; B i is the length of the equivalent foundation, i = I, II, III, and the values can be calculated according to the following formula:

[0184]

[0185] Among them, D’ is the diagonal length of the five-connected cylinder foundation,

[0186] In step 2, the position of the rotation axis of the five-connected cylinder foundation is the same as:

[0187]

[0188] In step 3, according to the overturning failure mode of the five-connected cylinder foundation, it is determined that the resistance moment of the foundation under the action of the overturning load is mainly provided by the resistance moment M p generated by the passive wedge zone, the resistance moment M f generated by the circular failure zone, and the resistance moment M s generated by the shear force between the sliding failure zone and the adjacent non-sliding zone soil body.

[0189] The resistance moment M p (only exists when z M > 0.5L) is:

[0190]

[0191] The resistance moment M f generated by the circular failure zone is:

[0192]

[0193] The resistance moment M s (only exists when z M > 0.5L) generated by the shear force between the sliding failure zone and the adjacent non-sliding zone soil body is:

[0194]

[0195] In Step 4, according to the principle of moment balance, the ultimate anti-overturning bearing capacity of the five-barrel foundation is:

[0196] M = M p + M f + M s

[0197] In Step 5, considering the influence of the eccentricity of the rotation axis, the corrected ultimate anti-overturning bearing capacity of the five-barrel foundation is:

[0198] M cor = M p + ξM f + M s

[0199] where ξ is the correction coefficient. For the diagonal loading condition in homogeneous clay, ξ = 0.9 - 1.0. For the five-barrel foundation with a relatively small length-diameter ratio, ξ takes the smaller value within the range; for the five-barrel foundation with a relatively large length-diameter ratio, ξ takes the larger value within the range.

[0200] (3) Opposite-side loading condition in normally consolidated clay

[0201] In Step 1, according to the equivalent diagram of the anti-overturning bearing of the five-barrel foundation, the five-barrel foundation is equivalent to a Type I foundation and two Type II foundations; B i is the length of the equivalent foundation, i = I, II, and the values are calculated according to the following formula.

[0202]

[0203] In Step 2, propose the overturning failure mode of the five-barrel foundation and determine the position of the rotation axis of the five-barrel foundation as:

[0204]

[0205] In Step 3, according to the overturning failure mode of the five-barrel foundation, it is determined that the resistance moment of the foundation under the action of the overturning load is mainly provided by the resistance moment M a,p generated by the wedge failure zone, the resistance moment M f generated by the circular arc failure zone, and the resistance moment M s generated by the shear force between the sliding failure zone and the adjacent non-sliding zone soil, which are three parts.

[0206] The resistance moment M a,p (only exists when z M > 0.5L) is:

[0207]

[0208] Among them, E a is the unit earth pressure generated by the soil mass in the active zone of the wedge on each equivalent foundation; N a is the coefficient of active earth pressure, z a is the distance from the acting point of the unit earth pressure E a to the bottom of the active zone of the wedge; the undrained shear strength s of the soil mass u is taken as k·z w / 2, where k is the change gradient of the undrained shear strength of the soil mass.

[0209] The resisting moment M generated by the circular arc failure zone is f as follows:

[0210]

[0211] Among them, the undrained shear strength s of the soil mass uf1i , s uf2i is calculated and taken as follows:

[0212]

[0213] The resisting moment M generated by the shear force between the sliding failure zone and the adjacent non-sliding zone soil mass s includes two parts: one part is the resisting moment M s1 generated by the shear force between the sliding surfaces on both sides of the wedge and the adjacent non-sliding zone soil mass; s2 the other part is the resisting moment M

[0214] The resisting moment M s1 (only exists when z M > 0.5L) is as follows:

[0215]

[0216] Among them, the undrained shear strength s of the soil mass u is taken as k·z w / 2.

[0217] The resisting moment M s2 is as follows:

[0218]

[0219] Among them, the undrained shear strength s of the soil mass usi is calculated and taken as follows:

[0220]

[0221] The resistance moment M generated by the shear force between the sliding failure zone and the adjacent non-sliding zone of the soil mass s is:

[0222] M s = 4M s1 + 2M s2

[0223] In step 4, according to the principle of moment balance, the ultimate anti-overturning bearing capacity of the five-connected cylinder foundation is:

[0224] M = M a,p + M f + M s

[0225] In step 5, considering the influence of the eccentricity of the rotation axis, the corrected ultimate anti-overturning bearing capacity of the five-connected cylinder foundation is:

[0226] M cor = M a,p + ξM f + M s

[0227] where ξ is the correction coefficient. For the opposite-side loading condition in normally consolidated clay, ξ = 0.9 - 0.95. For the five-connected cylinder foundation with a relatively small length-diameter ratio, ξ takes the smaller value within the range; for the five-connected cylinder foundation with a relatively large length-diameter ratio, ξ takes the larger value within the range.

[0228] (4) Diagonal loading condition in normally consolidated clay

[0229] In step 1, according to the equivalent schematic diagram of the anti-overturning bearing of the five-connected cylinder foundation, the five-connected cylinder foundation is equivalent to one type-I foundation, two type-II foundations, and two type-III foundations; B i is the length of the equivalent foundation, i = I, II, III, and the following formula is used for calculation and value taking.

[0230]

[0231] In step 2, the position of the rotation axis of the five-connected cylinder foundation is the same as:

[0232]

[0233] In step 3, the resistance moment M a,p (only exists when z M > 0.5L) generated by the wedge failure zone is:

[0234]

[0235] where the undrained shear strength s u of the soil mass is taken as k·z w / 2.

[0236] The resisting moment M generated by the circular arc failure zone f is as follows:

[0237]

[0238] Among them, the undrained shear strength s of the soil mass uf1i 、s uf2i is calculated and taken according to the following formula:

[0239]

[0240] The resisting moment M generated by the shear force between the sliding failure zone and the adjacent non-sliding zone soil mass s (only exists when z M > 0.5L) is as follows:

[0241]

[0242] Among them, the undrained shear strength s of the soil mass u is taken as k·z w / 2.

[0243] In step 4, according to the principle of moment balance, the ultimate anti-overturning bearing capacity of the five-connected cylinder foundation is:

[0244] M = M a,p + M f + M s

[0245] In step 5, considering the influence of the eccentricity of the rotation axis, the corrected ultimate anti-overturning bearing capacity of the five-connected cylinder foundation is:

[0246] M cor = M a,p + ξM f + M s

[0247] Among them, ξ is the correction coefficient. For the edge loading condition in normally consolidated clay, ξ = 0.95 - 1.0. For the five-connected cylinder foundation with a relatively small aspect ratio, ξ takes the smaller value within the range; for the five-connected cylinder foundation with a relatively large aspect ratio, ξ takes the larger value within the range.

[0248] Specifically, for a certain offshore wind power project that plans to use a five-connected cylinder foundation for bearing, the basic parameters of the five-connected cylinder foundation and the soil mass are shown in Table 1 and Table 2 respectively, and the load application directions are edge loading and diagonal loading.

[0249] Table 1 Five-connected cylinder foundation size design

[0250]

[0251] Table 2 Soil parameters

[0252]

[0253] Note: The undrained shear strength s of normally consolidated clay u = kz = 1.2z is the overall distribution law of the shear strength of the soil mass. However, the specific shear strength of the soil mass corresponding in the above formula (including: s uf1i 、s uf2i 、s usi etc.) is the final distribution law of the shear strength of the soil mass given after considering other influencing factors. Therefore, in specific calculations, the undrained shear strength of the soil mass corresponding in the formula is still used for value taking.

[0254] First, according to the plan view of the five-connected cylinder foundation structure under the opposite-side loading condition, as Figure 5 shown, calculate the key geometric parameter values:

[0255]

[0256] (1) Opposite-side loading condition in homogeneous clay

[0257] According to the anti-overturning bearing equivalent diagram of the five-connected cylinder foundation in homogeneous clay, see Figure 1 in (a) the opposite-side loading condition, the five-connected cylinder foundation is equivalent to a type-I foundation and two type-II foundations; B i is the length of the equivalent foundation, i = I, II. Combining Figure 5 , the following formula can be used for calculation and value taking:

[0258]

[0259] The position of the rotation axis of the five-connected cylinder foundation is:

[0260]

[0261] According to the overturning failure mode of the five-connected cylinder foundation, as Figure 2 shown in part (a), it is determined that the resistance moment of the foundation under the action of the overturning load is mainly provided by the resistance moment M p generated by the passive zone of the wedge, the resistance moment M f generated by the circular arc failure zone, and the resistance moment M s generated by the shear force between the sliding failure zone and the adjacent non-sliding zone soil mass.

[0262] The first part of the resistance moment M p (only exists when z M > 0.5L) calculation:

[0263] The unit earth pressure generated by the soil mass in the passive zone of the wedge on various equivalent foundations:

[0264]

[0265] Among them, the coefficient of passive earth pressure:

[0266] The overturning resistance moment generated by the wedge failure zone corresponding to various equivalent foundations:

[0267]

[0268] The overturning resistance moment generated by the passive zone of the wedge:

[0269]

[0270] The second part of the resistance moment M f Calculation:

[0271] The overturning resistance moment generated by the circular arc failure zone corresponding to various equivalent foundations:

[0272]

[0273] Among them, R M , α M , β M , β’ M , θ M and other key geometric parameters are:

[0274]

[0275] Since B i is a dependent variable of ω, the above key geometric parameters cannot be calculated to obtain specific values, but directly participate in the calculation during the integration process, so as to obtain the overturning resistance moment generated by the circular arc failure zone corresponding to various equivalent foundations.

[0276] The overturning resistance moment generated by the circular arc failure zone:

[0277]

[0278] The third part of the resistance moment M s Calculation:

[0279] The resistance moment M s1 (Only exists when z M > 0.5L):

[0280]

[0281] The resistance moment M s2 is:

[0282]

[0283] Among them, the distance between the centers of two adjacent side cylinders: D3 = D - D2 = 25 m.

[0284] The resistance moment M generated by the shear force between the sliding failure zone and the adjacent non-sliding zone soil s is:

[0285]

[0286] According to the moment balance principle, the ultimate anti-overturning bearing capacity of the five-cylinder foundation is:

[0287]

[0288] Considering the influence of the eccentricity of the rotation axis, the corrected ultimate anti-overturning bearing capacity of the five-cylinder foundation is:

[0289]

[0290] Among them, ξ = 0.95.

[0291] (2) Diagonal loading condition in homogeneous clay

[0292] According to the anti-overturning bearing capacity equivalent schematic diagram of the five-cylinder foundation in homogeneous clay, see Figure 1 in (b) the diagonal loading condition, the five-cylinder foundation is equivalent to one type I foundation, two type II foundations and two type III foundations; B i is the length of the equivalent foundation, i = I, II, III, combined with Figure 6 , the following formula can be used for calculation and value taking:

[0293]

[0294] The position of the rotation axis of the five-cylinder foundation is:

[0295]

[0296] According to the overturning failure mode of the five-cylinder foundation, as shown in Figure 2 (a) part of it, it is determined that the resistance moment of the foundation under the action of the overturning load is mainly generated by the resistance moment M p of the passive wedge zone, the resistance moment M f generated by the circular arc failure zone, and the resistance moment M s generated by the shear force between the sliding failure zone and the adjacent non-sliding zone soil.

[0297] The first part of the resistance moment M p (only exists when z M > 0.5L) is calculated as:

[0298] Unit earth pressure generated by the wedge passive zone soil on various equivalent foundations:

[0299]

[0300] Overturning resistance moment generated by the wedge failure zone corresponding to various equivalent foundations:

[0301]

[0302] The overturning resistance moment generated by the passive zone of the wedge is:

[0303]

[0304] The second part of the resistance moment M f calculate:

[0305] The overturning resistance moment generated by the arc-shaped failure zone corresponding to various equivalent foundations is:

[0306]

[0307] Overturning resistance moment generated by the arc-shaped failure zone:

[0308]

[0309] Part 3 Resistance moment M s calculate:

[0310] Resistance moment M s1 (Only when z M >0.5L):

[0311]

[0312] The resistance moment M generated by the shear force between the sliding failure zone and the adjacent non-sliding zone soil s for:

[0313]

[0314] According to the moment balance principle, the ultimate anti-overturning bearing capacity of the five-tube foundation is:

[0315]

[0316] Considering the influence of the eccentricity of the rotation axis, the revised ultimate anti-overturning bearing capacity of the five-tube foundation is:

[0317]

[0318] Where ξ = 1.0.

[0319] (3) Side loading in normally consolidated clay

[0320] According to the anti-overturning bearing capacity equivalent schematic diagram of the five-connected cylinder foundation in normally consolidated clay, as shown in Figure 3 In the case of side loading in (a) below, the five-connected cylinder foundation is equivalent to a type-I foundation and two type-II foundations; B i is the length of the equivalent foundation, i = I, II. Combining Figure 5 , the calculation value can be obtained according to the following formula:

[0321]

[0322] The position of the rotation axis of the five-connected cylinder foundation is:

[0323]

[0324] According to the overturning failure mode of the five-connected cylinder foundation, as shown in Figure 4 (a) below, it is determined that the resistance moment of the foundation under the action of the overturning load is mainly provided by the resistance moment M a,p generated by the wedge failure zone, the resistance moment M f generated by the circular arc failure zone, and the resistance moment M s generated by the shear force between the sliding failure zone and the adjacent non-sliding zone soil body.

[0325] The first part of the resistance moment M a,p (only exists when z M > 0.5L) is calculated as follows:

[0326] The unit earth pressure generated by the soil body in the wedge failure zone on various equivalent foundations:

[0327]

[0328] Among them, the active earth pressure coefficient: The undrained shear strength s of the soil body u = 1.2z w / 2 = 1.26 kPa.

[0329] The overturning resistance moment generated by the wedge failure zone corresponding to various equivalent foundations:

[0330]

[0331] The overturning resistance moment generated by the wedge failure zone:

[0332]

[0333] The second part of the resistance moment M f is calculated as follows:

[0334] The overturning resistance moment generated by the circular arc failure zone corresponding to various equivalent foundations:

[0335]

[0336] Among them, the undrained shear strength s of the soil mass uf1i 、s uf2i is calculated and taken according to the following formula:

[0337]

[0338] The overturning resistance moment generated by the circular arc failure zone:

[0339]

[0340] The third part of the resistance moment M s is calculated as:

[0341] The resistance moment M s1 (only exists when z M > 0.5L):

[0342]

[0343] Among them, the undrained shear strength s of the soil mass u = 1.2z w / 2 = 1.26 kPa.

[0344] The resistance moment M s2 is:

[0345]

[0346] Among them, the undrained shear strength s of the soil mass usi is calculated and taken according to the following formula:

[0347]

[0348] The resistance moment M generated by the shear force between the sliding failure zone and the adjacent non-sliding zone soil mass<s s is:

[0349]

[0350] According to the principle of moment balance, the ultimate anti-overturning bearing capacity of the five-connected cylinder foundation is:

[0351]

[0352] Considering the influence of the eccentricity of the rotation axis, the corrected ultimate anti-overturning bearing capacity of the five-connected cylinder foundation is:

[0353]

[0354] Among them, ξ = 0.95.

[0355] (4) Diagonal loading condition in normally consolidated clay

[0356] According to the anti-overturning bearing capacity equivalent schematic diagram of the five-connected cylinder foundation in normally consolidated clay, as shown in Figure 3 (b) in the diagonal loading condition, the five-connected cylinder foundation is equivalent to one type-I foundation, two type-II foundations and two type-III foundations; B i is the length of the equivalent foundation, i = I, II, III. Combining with Figure 6 , the calculation value can be obtained according to the following formula:

[0357]

[0358] The position of the rotation axis of the five-connected cylinder foundation is:

[0359]

[0360] According to the overturning failure mode of the five-connected cylinder foundation, as shown in Figure 4 (a) in the figure, it is determined that the resistance moment of the foundation under the action of the overturning load is mainly provided by the resistance moment M a,p generated by the wedge failure zone, the resistance moment M f generated by the circular arc failure zone, and the resistance moment M s generated by the shear force between the sliding failure zone and the adjacent non-sliding zone soil body.

[0361] The first part of the resistance moment M a,p (only exists when z M > 0.5L) is calculated as follows:

[0362] The unit soil pressure generated by the soil body in the wedge failure zone on various equivalent foundations:

[0363]

[0364] Among them, the undrained shear strength s u of the soil body = 1.2z w / 2 = 1.26 kPa.

[0365] The overturning resistance moment generated by the wedge failure zone corresponding to various equivalent foundations:

[0366]

[0367] The overturning resistance moment generated by the wedge failure zone:

[0368]

[0369] The second part of the resistance moment M f is calculated as follows:

[0370] The overturning resistance moment generated by the circular failure zones corresponding to various equivalent foundations:

[0371]

[0372] Among them, the undrained shear strength of the soil s uf1i 、s uf2i is calculated and taken according to the following formula:

[0373]

[0374] The overturning resistance moment generated by the circular failure zone:

[0375]

[0376] The third part of the resistance moment M s is calculated as:

[0377] The resistance moment M s1 (only exists when z M > 0.5L):

[0378]

[0379] Among them, the undrained shear strength of the soil s u = 1.2z w / 2 = 1.26 kPa.

[0380] The resistance moment M generated by the shear force between the sliding failure zone and the adjacent non-sliding zone of the soil s is:

[0381]

[0382] According to the principle of moment balance, the ultimate anti-overturning bearing capacity of the five-tube foundation is:

[0383]

[0384] Considering the influence of the eccentricity of the rotation axis, the corrected ultimate anti-overturning bearing capacity of the five-tube foundation is:

[0385]

[0386] Among them, ξ = 1.0.

[0387] Preferably, the embodiment of the present application further provides a calculation device for the ultimate anti-overturning bearing capacity of an offshore wind power five-tube foundation, including:

[0388] An equivalent unit, configured to equivalent the five-tube foundation into several foundations with regular shapes according to the anti-overturning bearing capacity equivalent schematic diagram of the five-tube foundation;

[0389] A mode setting unit for setting the overturning failure mode of the five - connected cylinder foundation and determining the position of the rotation axis of the five - connected cylinder foundation;

[0390] A resistance moment determination unit for determining the components of the resistance moment of the five - connected cylinder foundation under the action of an overturning load according to the overturning failure mode of the five - connected cylinder foundation, including the resistance moment M a,p generated in the wedge - shaped failure zone, the resistance moment M f generated in the circular - arc failure zone, and the resistance moment M s generated by the shear force between the sliding failure zone and the adjacent non - sliding zone soil, which are three parts;

[0391] A calculation unit for obtaining the ultimate anti - overturning bearing capacity of the five - connected cylinder foundation according to the principle of moment balance;

[0392] A correction unit for considering the influence of the eccentricity of the rotation axis on the resistance moment M f generated in the circular - arc failure zone and correcting the ultimate anti - overturning bearing capacity of the five - connected cylinder foundation.

[0393] Preferably, the embodiment of the present application further provides a specific implementation manner of an electronic device that can implement all the steps in the calculation method of the ultimate anti - overturning bearing capacity of the offshore wind power five - connected cylinder foundation in the above - mentioned embodiment. The electronic device specifically includes the following:

[0394] A processor, a memory, a communication interface, and a bus;

[0395] Among them, the processor, the memory, and the communication interface complete mutual communication through the bus; the communication interface is used to realize information transmission between related devices such as server - side devices, metering devices, and user - side devices.

[0396] The processor is used to call the computer program in the memory. When the processor executes the computer program, it realizes all the steps in the calculation method of the ultimate anti - overturning bearing capacity of the offshore wind power five - connected cylinder foundation in the above - mentioned embodiment.

[0397] The embodiment of the present application also provides a computer - readable storage medium that can implement all the steps in the calculation method of the ultimate anti - overturning bearing capacity of the offshore wind power five - connected cylinder foundation in the above - mentioned embodiment. A computer program is stored on the computer - readable storage medium, and when the computer program is executed by the processor, it realizes all the steps in the calculation method of the ultimate anti - overturning bearing capacity of the offshore wind power five - connected cylinder foundation in the above - mentioned embodiment.

[0398] Each embodiment in this specification is described in a progressive manner. For the same or similar parts among the embodiments, reference can be made to each other, and the key point of each embodiment is to illustrate the differences from other embodiments. In particular, for the hardware + program type of embodiments, since they are basically similar to the method embodiments, the description is relatively simple, and reference can be made to the corresponding parts of the method embodiments for the relevant content.

[0399] The above describes specific embodiments of this specification. Other embodiments are within the scope of the appended claims. In some cases, the actions or steps recited in the claims can be performed in a different order than in the embodiments and still achieve the desired results. Additionally, the processes depicted in the figures do not necessarily require the particular order or sequential order shown to achieve the desired results. In certain embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0400] Although this application provides method operation steps such as in the embodiments or flowcharts, more or fewer operation steps may be included based on routine or non-creative labor. The order of steps listed in the embodiments is only one way among the numerous execution orders of the steps and does not represent the only execution order. When the actual device or client product is executed, it can be executed in the order shown in the embodiments or the figures or in parallel (such as in an environment of parallel processors or multi-threaded processing).

[0401] Those skilled in the art should understand that the embodiments of the present invention can be provided as a method, a system, or a computer program product. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Moreover, the present invention can take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) that contain computer-usable program code.

[0402] These computer program instructions can also be stored in a computer-readable memory that can direct a computer or other programmable data processing device to work in a specific manner, such that the instructions stored in the computer-readable memory produce a manufactured article including an instruction device, and the instruction device implements the functions specified in Figure 1 one process or multiple processes and / or Figure 1 boxes or multiple boxes.

[0403] These computer program instructions can also be loaded onto a computer or other programmable data processing device, such that a series of operation steps are performed on the computer or other programmable device to produce a computer-implemented process, and thus the instructions executed on the computer or other programmable device provide for implementing the functions specified in the process Figure 1One process or multiple processes and / or boxes Figure 1 Steps of the functions specified in one box or multiple boxes.

[0404] The present invention is not limited to the embodiments described above. The above description of the specific embodiments is intended to describe and illustrate the technical solutions of the present invention. The above specific embodiments are merely illustrative and not restrictive. Without departing from the spirit of the present invention and the scope protected by the claims, those of ordinary skill in the art can also make many specific transformations in form under the inspiration of the present invention, and these all fall within the protection scope of the present invention.

Claims

1. A calculation method for the anti-overturning ultimate bearing capacity of a five-cylinder foundation for offshore wind power, characterized in that, It includes the following steps: S1. According to the equivalent diagram of the anti-overturning bearing capacity of the five-connected cylinder foundation, the five-connected cylinder foundation is equivalent to several foundations with regular shapes; S2. Propose the overturning failure mode of the five-connected cylinder foundation and determine the position of the rotation axis of the five-connected cylinder foundation; S3. Determine the components of the resistance moment of the five-barrel foundation under the action of the overturning load according to the overturning failure mode of the five-barrel foundation, including the resistance moment M generated in the wedge failure zone a,p , the resistance moment M generated in the circular arc failure zone f and the resistance moment M generated by the shear force between the sliding failure zone and the adjacent non-sliding zone soil mass s These are three parts; S4. According to the principle of moment balance, obtain the ultimate anti-overturning bearing capacity of the five-connected cylinder foundation; S5. Consider the influence of the eccentricity of the rotation axis on the moment of resistance M f generated by the circular failure zone, and correct the ultimate anti-overturning bearing capacity of the five-barrel foundation obtained in step S4.

2. The calculation method for the anti-overturning ultimate bearing capacity of a five-tube foundation for offshore wind power according to claim 1, characterized in that, It is applicable to different working conditions, including the opposite-side loading condition in homogeneous clay, the diagonal loading condition in homogeneous clay, the opposite-side loading condition in normally consolidated clay, and the diagonal loading condition in normally consolidated clay; Among them, the opposite-side loading condition and the diagonal loading condition are distinguished according to the angle at which the overturning load acts on the five-connected cylinder foundation. The opposite-side loading condition is that the overturning moment is loaded in the 0° direction, and the diagonal loading condition is that the overturning moment is loaded in the 45° direction; Homogeneous clay and normally consolidated clay are distinguished according to the distribution law of the undrained shear strength s of the soil mass u along the depth direction of the soil mass. Homogeneous clay is the undrained shear strength s of the soil mass u showing a uniform distribution law along the depth direction of the soil mass, and normally consolidated clay is the undrained shear strength s of the soil mass u showing a linear distribution law along the depth direction of the soil mass.

3. The calculation method for the anti-overturning ultimate bearing capacity of the five-connected barrel foundation for offshore wind power according to claim 2, wherein, For the opposite-side loading condition in homogeneous clay: In step S1, according to the equivalent diagram of the anti-overturning bearing capacity of the five-barrel foundation, the five-barrel foundation is equivalent to a type-I foundation and two type-II foundations. B i is the length of the equivalent foundation, and i = I, II. The values are calculated according to the following formula: Where D is the opposite-side length of the five-connected cylinder foundation; D1 is the diameter of the middle cylinder of the five-connected cylinder foundation; D2 is the diameter of the side cylinder of the five-connected cylinder foundation; ω is an intermediate variable in the solution process; α is a geometric parameter. The following gives the value-taking methods of several key geometric parameters: In step S2, propose the overturning failure mode of the five-connected cylinder foundation, and determine the position of the rotation axis of the five-connected cylinder foundation as: where z M is the height of the rotation axis, and L is the height of the five-connected cylinder foundation; In step S3, the resistance moment M generated in the passive zone of the wedge p exists only when z M > 0.5L, specifically: Among them, E p is the unit earth pressure generated by the soil mass in the passive zone of the wedge on each equivalent foundation; N p is the coefficient of passive earth pressure, μ is the friction coefficient between the sliding wedge and the foundation; γ’ is the unit weight of the soil mass; z w is the height of the wedge; z p is the distance from the acting point of the earth pressure E p to the bottom of the passive zone of the wedge; The resisting moment M generated by the circular arc failure zone f is as follows: Among them, R M is the radius of the circular arc sliding surface, and α M , β M , β’ M , θ M are the geometric parameters in the failure mode diagram of the five - connected cylinder foundation under the action of the overturning load, and satisfy the following relationships: The resisting moment M generated by the shear force between the sliding failure zone and the adjacent non-sliding zone soil s It includes two parts: one part is the resisting moment M generated by the shear force between the sliding surfaces on both sides of the wedge and the adjacent non-sliding zone soil s1 ; the other part is the resisting moment M generated by the shear force between the rotational sliding surface of the soil in the middle of the adjacent side cylinder and the non-sliding zone soil s2 ; Resisting moment M s1 Exists only when z M > 0.5L, and is: Among them, Resisting moment M s2 is as follows: Among them, R Ms is the radius of the torsional shear plane; D3 is the distance between the centers of two adjacent side cylinders, that is, B i = D3 = D - D2; ρ is an intermediate variable in the solution process; The resistance moment M generated by the shear force between the sliding failure zone and the soil mass in the adjacent non-sliding zone s is as follows: M s = 2M s1 + 2M s2 In step S4, according to the principle of moment balance, the ultimate anti-overturning bearing capacity of the five-connected cylinder foundation is: M = M p +M f +M s In step S5, considering the influence of the eccentricity of the rotation axis, the corrected ultimate anti-overturning bearing capacity of the five-connected cylinder foundation is: M cor = M p + ξM f + M s Where ξ is the correction coefficient. For the opposite-side loading condition in homogeneous clay, ξ = 0.85 - 0.

95. For the five-connected cylinder foundation with a relatively small aspect ratio, ξ takes the smaller value within the range; for the five-connected cylinder foundation with a relatively large aspect ratio, ξ takes the larger value within the range.

4. The calculation method for the anti-overturning ultimate bearing capacity of a five-tube foundation for offshore wind power according to claim 2, characterized in that, For the diagonal loading condition in homogeneous clay: In step S1, according to the equivalent schematic diagram of the anti-overturning bearing capacity of the five-connected cylinder foundation, the five-connected cylinder foundation is equivalent to one type-I foundation, two type-II foundations, and two type-III foundations; B i is the length of the equivalent foundation, i = I, II, III, and the calculation value is obtained according to the following formula: Among them, D’ is the diagonal length of the five-connected cylinder foundation, and D2 is the diameter of the side cylinder of the five-connected cylinder foundation. ω is an intermediate variable in the solution process; In step S2, the position of the rotation axis of the five-connected cylinder foundation is the same as: where z M is the height of the rotating shaft, and L is the height of the five-barrel base; In step S3, the resistance moment M generated in the passive zone of the wedge p exists only when z M > 0.5L, specifically: Among them, E p is the unit earth pressure generated by the soil mass in the passive zone of the wedge on each equivalent foundation; N p is the coefficient of passive earth pressure, μ is the friction coefficient between the sliding wedge and the foundation; γ’ is the unit weight of the soil mass; z w is the height of the wedge; z p is the distance from the acting point of the earth pressure E p to the bottom of the passive zone of the wedge; The resisting moment M generated by the circular arc failure zone f is as follows: Among them, R M is the radius of the circular arc sliding surface, α M , β M , β’ M are geometric parameters in the failure mode diagram of the five-connected cylinder foundation under the action of the overturning load, and satisfy the following relationship: The resisting moment M generated by the shear force between the sliding failure zone and the adjacent non-sliding zone soil s Exists only when z M > 0.5L, specifically: Among them, In step S4, according to the principle of moment balance, the ultimate anti-overturning bearing capacity of the five-connected cylinder foundation is: M = M p + M f + M s In step S5, considering the influence of the eccentricity of the rotation axis, the corrected ultimate anti-overturning bearing capacity of the five-connected cylinder foundation is: M cor = M p + ξM f + M s Where ξ is the correction coefficient. For the diagonal loading condition in homogeneous clay, ξ = 0.9 - 1.

0. For the five-connected cylinder foundation with a relatively small aspect ratio, ξ takes the smaller value within the range; for the five-connected cylinder foundation with a relatively large aspect ratio, ξ takes the larger value within the range.

5. The calculation method for the anti-overturning ultimate bearing capacity of a five-tube foundation for offshore wind power according to claim 2, characterized in that, For the opposite-side loading condition in normally consolidated clay: In step S1, according to the equivalent schematic diagram of the anti-overturning bearing capacity of the five-barrel foundation, the five-barrel foundation is equivalent to a type-I foundation and two type-II foundations; B i is the length of the equivalent foundation, i = I, II, and the calculation value is obtained according to the following formula: Where D is the opposite-side length of the five-connected cylinder foundation; D1 is the diameter of the middle cylinder of the five-connected cylinder foundation; D2 is the diameter of the side cylinder of the five-connected cylinder foundation; ω is an intermediate variable in the solution process; α is a geometric parameter. The following gives the value-taking methods of several key geometric parameters: In step S2, propose the overturning failure mode of the five-connected cylinder foundation, and determine the position of the rotation axis of the five-connected cylinder foundation as: where z M is the height of the rotation axis, and L is the height of the five - cylinder base; In step 3, the resistance moment M generated in the wedge failure zone a,p Exists only when z M > 0.5L, specifically: Among them, E p is the unit earth pressure generated by the soil mass in the passive zone of the wedge on each equivalent foundation; N p is the coefficient of passive earth pressure, γ’ is the unit weight of the soil mass; z w is the height of the wedge; z p is the distance from the acting point of the earth pressure E p to the bottom of the passive zone of the wedge; E a is the unit earth pressure generated by the soil mass in the active zone of the wedge on each equivalent foundation; N a is the coefficient of active earth pressure, z a is the distance from the acting point of the unit earth pressure E a to the bottom of the active zone of the wedge; the undrained shear strength s of the soil mass u is taken as k·z w / 2, where k is the change gradient of the undrained shear strength of the soil mass; The resistance moment M generated by the circular arc failure zone f is as follows: Among them, R M is the radius of the circular arc sliding surface, α M , β M , β’ M , θ M are geometric parameters in the failure mode diagram of the five-connected cylinder foundation under the action of the overturning load, and satisfy the following relationships: Undrained shear strength s of soil mass uf1i 、s uf2i The value is calculated according to the following formula: The resisting moment M generated by the shear force between the sliding failure zone and the soil in the adjacent non-sliding zone s consists of two parts: one part is the resisting moment M generated by the shear force between the sliding surfaces on both sides of the wedge and the soil in the adjacent non-sliding zone s1 ; the other part is the resisting moment M generated by the shear force between the rotational sliding surface of the soil in the middle of the adjacent side cylinders and the soil in the non-sliding zone s2 ; Resisting moment M s1 Exists only when z M > 0.5L, and is: Among them, undrained shear strength s of soil mass u is taken as k·z w / 2; Resisting moment M s2 is as follows: Among them, R Ms is the radius of the torsional shear plane; D3 is the distance between the centers of two adjacent side cylinders, that is, B i = D3 = D - D2; ρ is an intermediate variable in the solution process; Undrained shear strength s of soil mass usi The value is calculated according to the following formula: The resisting moment M generated by the shear force between the sliding failure zone and the adjacent non-sliding zone soil s is as follows: M s = 4M s1 + 2M s2 In step S4, according to the principle of moment balance, the ultimate anti-overturning bearing capacity of the five-connected cylinder foundation is: M = M a,p +M f +M s In step S5, considering the influence of the eccentricity of the rotation axis, the corrected ultimate anti-overturning bearing capacity of the five-connected cylinder foundation is: M cor = M a,p + ξM f + M s Where ξ is the correction coefficient. For the opposite-side loading condition in normally consolidated clay, ξ = 0.9 - 0.

95. For the five-connected cylinder foundation with a relatively small aspect ratio, ξ takes the smaller value within the range; for the five-connected cylinder foundation with a relatively large aspect ratio, ξ takes the larger value within the range.

6. The calculation method for the anti-overturning ultimate bearing capacity of a five-tube foundation for offshore wind power according to claim 2, wherein For the diagonal loading condition in normally consolidated clay: In step S1, according to the equivalent diagram of the anti-overturning bearing capacity of the five-connected cylinder foundation, the five-connected cylinder foundation is equivalent to one type-I foundation, two type-II foundations, and two type-III foundations; B i is the length of the equivalent foundation, and i = I, II, III. The values are calculated according to the following formula: Wherein, D’ is the diagonal length of the five-connected cylinder foundation, and D2 is the diameter of the side cylinder of the five-connected cylinder foundation. ω is an intermediate variable in the solution process; In step S2, the position of the rotation axis of the five - cylinder foundation is the same as: where z M is the height of the rotation axis, and L is the height of the foundation of the five-connected cylinder; In step S3, the resistance moment M generated in the wedge failure zone a,p Exists only when z M > 0.5L, specifically: Among them, E p is the unit earth pressure generated by the soil mass in the passive zone of the wedge on each equivalent foundation; N p is the coefficient of passive earth pressure, γ’ is the unit weight of the soil mass; z w is the height of the wedge; z p is the distance from the acting point of the earth pressure E p to the bottom of the passive zone of the wedge; E a is the unit earth pressure generated by the soil mass in the active zone of the wedge on each equivalent foundation; N a is the coefficient of active earth pressure, z a is the distance from the acting point of the unit earth pressure E a to the bottom of the active zone of the wedge; the undrained shear strength s of the soil mass u is taken as k·z w / 2, where k is the change gradient of the undrained shear strength of the soil mass; The resistance moment M generated by the circular arc failure zone f is as follows: Among them, R M is the radius of the circular arc sliding surface, and α M , β M , β’ M are geometric parameters in the failure mode diagram of the five-connected cylinder foundation under the action of the overturning load, and satisfy the following relationship: Undrained shear strength s of soil mass uf1i 、s uf2i The value is calculated and obtained according to the following formula: The resisting moment M generated by the shear force between the sliding failure zone and the adjacent non-sliding zone soil s Exists only when z M > 0.5L, and is: Among them, In step S4, according to the principle of moment balance, the ultimate anti - overturning bearing capacity of the five - cylinder foundation is: M = M a,p + M f + M s In step S5, considering the influence of the eccentricity of the rotation axis, the corrected ultimate anti - overturning bearing capacity of the five - cylinder foundation is: M cor = M a,p + ξM f + M s Where ξ is the correction coefficient. For the opposite - side loading condition in normally consolidated clay, ξ = 0.95 - 1.

0. For the five - cylinder foundation with a relatively small length - diameter ratio, ξ takes the smaller value within the range; for the five - cylinder foundation with a relatively large length - diameter ratio, ξ takes the larger value within the range.

7. An anti-overturning ultimate bearing capacity calculation device for a five-connected barrel foundation of offshore wind power, characterized in that, Including: An equivalent unit, which is used to equivalent the five - cylinder foundation into several foundations with regular shapes according to the anti - overturning bearing capacity equivalent schematic diagram of the five - cylinder foundation; A mode - setting unit, which is used to set the overturning failure mode of the five - cylinder foundation and determine the position of the rotation axis of the five - cylinder foundation; A resistance moment determination unit determines the components of the resistance moment of a five-connected cylinder foundation under an overturning load according to the overturning failure mode of the five-connected cylinder foundation, including the resistance moment M generated in the wedge failure area a,p , the resistance moment M generated in the circular arc failure area f and the resistance moment M generated by the shear force between the sliding failure area and the adjacent non-sliding area soil s in three parts; A calculation unit, which is used to obtain the ultimate anti - overturning bearing capacity of the five - cylinder foundation according to the principle of moment balance; A correction unit for correcting the ultimate anti-overturning bearing capacity of the five-connected cylinder foundation by considering the influence of the eccentricity of the rotation axis on the resistance moment M f generated by the circular failure zone.

8. An electronic device, comprising a memory, a processor, and a computer program stored on the memory and executable on the processor, characterized in that, When the processor executes the program, it realizes the steps of the calculation method for the ultimate anti - overturning bearing capacity of the offshore wind power five - cylinder foundation according to any one of claims 1 to 6.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it realizes the steps of the calculation method for the ultimate anti - overturning bearing capacity of the offshore wind power five - cylinder foundation according to any one of claims 1 to 6.

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