A wind turbine generator concrete ring piece and a design method thereof

Abstract

The application discloses a kind of wind turbine concrete ring piece and its design method, belong to wind farm construction field, the design method of wind turbine concrete ring piece includes the following steps: according to the design load requirement of variable diameter tower section, the thickness of UHPC layer in concrete ring piece is determined;The UHPC layer of variable diameter concrete ring piece inner and outer wall is made of steel mold;Embedded connecting steel bar, pours the UHPC layer component of concrete ring piece inner and outer wall and maintains;After UHPC layer reaches the specified age requirement, UHPC layer is used as template, carries out inner layer steel bar binding, pours and maintains high-strength concrete core;After inner layer high-strength concrete core reaches the specified age, it is transported to the scene, carries out on-site hoisting and uses.The application is based on the stress characteristics of variable diameter tower section, proposes the calculation method of UHPC layer thickness, can obtain the minimum thin layer thickness that satisfies crack control, to obtain optimal concrete ring piece, meet the use demand.

Description

Technical Field

[0001] This invention relates to the field of wind farm construction, and in particular to a concrete ring for a wind turbine and its design method. Background Technology

[0002] With the rapid development of the wind power industry and the demand for development in low- and medium-wind-speed areas, pure steel towers are gradually being phased out, replaced by concrete-steel hybrid towers (referred to as hybrid towers). The rise of hybrid towers is a microcosm of the wind power industry's upgrade towards "high-altitude, low-cost, and safe and reliable" technologies. With the popularization of ultra-high-performance concrete technology and the maturity of intelligent construction systems, hybrid towers will become the dominant support structure in low- and medium-wind-speed areas, further driving down the cost of wind power.

[0003] The lower half of the hybrid tower is a concrete tower cylinder, which is constructed by sequentially splicing concrete rings, joints, tower sections, and tower segments. The centralized variable-diameter concrete tower is a wind turbine tower design that optimizes structural performance. Its main feature is performance optimization achieved through changes in cross-sectional dimensions at specific locations. The tower cylinder comprises multiple tower sections, which are sequentially spliced ​​together to form the tower cylinder. Each tower section consists of several concrete rings spliced ​​together to form a complete ring structure. A tower section whose cross-sectional dimensions change in the height direction is defined as a variable-diameter tower section. A tower segment containing a variable-diameter tower section is called a variable-diameter tower segment. A variable-diameter tower segment is composed of the variable-diameter tower section and the adjacent lower tower section, such as... Figure 1 As shown, Figure 1 1 is the variable diameter tower section, 2 is the concrete ring, 3 is the transverse joint, and 4 is the longitudinal joint.

[0004] In the structural system of a variable-diameter tower section, the long-term action of the upper vertical load causes continuous circumferential tensile stress at the bottom of the section. This accumulated circumferential tensile stress impacts structural safety and can easily lead to outward tensile deformation of the ring plates in the variable-diameter tower section, resulting in vertical through-cracks. Figure 2 and Figure 3 As shown, the finite element analysis results indicate that under vertical load, there is a significant circumferential deformation inflection point 5 in the middle of the ring plate TD. This means that the ring plate exhibits a bending stress characteristic of tension at the bottom and compression at the top along its vertical cross-section. Furthermore, the maximum circumferential deformation occurs at the lower edge of the ring plate TD, indicating that the bottom of the concentrated diameter-changing section is the starting point and the point of maximum width for vertical crack development. Therefore, cracking design should be implemented to ensure the safety and reliability of the structure. Due to deformation coordination, the maximum circumferential tensile deformation of segment A7 below the ring plate TD is located at the junction with the ring plate TD, indicating that segment A7, like the ring plate TD, bears a large circumferential force and is prone to cracking. Cracking design should be implemented accordingly. Segment B1 above the ring plate TD has a circumferential deformation inflection point approximately one-third of its length from the bottom, meaning the lower section is under compression and the upper section is under tension. Its deformation is smaller than that of the ring plate TD and segment A7. Although segment A6 is under tension across its entire cross-section, its circumferential deformation is relatively small due to its distance from the diameter-changing point.

[0005] Once cracks appear in the concrete ring, its internal structure becomes susceptible to water seepage, which in turn promotes the corrosion of the reinforcing steel. This not only seriously affects the normal use of the structure but may also pose a serious threat to its safety. Therefore, effective measures must be taken to properly address this issue. Summary of the Invention

[0006] To address the aforementioned technical problems, this invention provides a simple and reliable concrete ring for wind turbine generators, and also provides a design method for the concrete ring for wind turbine generators.

[0007] The technical solution of the present invention to solve the above-mentioned technical problems is: a concrete ring plate for a wind turbine, the tower of which includes multiple tower sections, each tower section being assembled sequentially to form the tower, each tower section being composed of several concrete ring plates spliced ​​together, the middle of the concrete ring plate being a high-strength concrete core, the inner and outer walls of the concrete ring plate being made of ultra-high performance concrete layer, the ultra-high performance concrete layer being a UHPC layer, the high-strength concrete core and the UHPC layer being spliced ​​together by mortise and tenon structure, and the UHPC layer and the high-strength concrete core being tightly connected by steel bars to form a whole.

[0008] In the above-mentioned wind turbine concrete ring, the tower section whose cross-sectional dimensions change in the height direction is defined as a variable diameter tower section. The tower segment containing the variable diameter tower section is called a variable diameter tower segment. The variable diameter tower segment is composed of the variable diameter tower section and the adjacent lower tower section.

[0009] A design method for concrete ring sections of a wind turbine generator includes the following steps:

[0010] Step 1: Determine the thickness of the UHPC layer in the concrete ring according to the design load requirements of the tower section at the diameter change.

[0011] Step 2: Fabricate steel molds for the UHPC layers on the inner and outer walls of the concrete ring at the diameter change point;

[0012] Step 3: Pre-embed connecting steel bars, pour concrete for the UHPC layer components on the inner and outer walls of the ring, and cure.

[0013] Step 4: After the UHPC layer reaches the specified age requirement, use the UHPC layer as a template to carry out the inner layer reinforcement binding, high-strength concrete core pouring and curing.

[0014] Step 5: After the inner high-strength concrete core reaches the specified age, it is transported to the site for on-site hoisting and use.

[0015] The above-mentioned design method for the concrete ring of a wind turbine, in step one, involves determining the thickness of the UHPC layer in the concrete ring as follows:

[0016] Step 1-1: Calculate the circumferential tensile force H using a simplified force model of the variable diameter tower section;

[0017] Step 1-2: Based on the deformation compatibility principle, the circumferential tensile force is distributed according to the axial tensile stiffness to determine the circumferential tensile force on the UHPC layer;

[0018] Steps 1-3: Based on the standard value of the tensile strength of the UHPC layer, calculate the minimum UHPC layer thickness that meets the crack resistance control requirements;

[0019] Steps 1-4: Verify the ultimate bearing capacity of the concrete ring and simultaneously check whether the high-strength concrete core has cracked.

[0020] The specific process of step 1-1 in the above-mentioned design method for concrete ring sections of wind turbine units is as follows:

[0021] The external load acting on the top of the reducing tower section is applied at the center of the top surface of the reducing tower section, with a circumferential width of [value missing]. dθ Force analysis of the tension / compression bar model is performed using narrow elements, and the equivalent compressive stress of the external load is applied to the centroid of the corresponding circular arc;

[0022] Analyze the vertical load at the top of the narrow element dP t and bottom vertical load dP b as follows:

[0023] (1)

[0024] (2)

[0025] In the formula, This represents the maximum compressive stress at the top section of the variable-diameter tower section; This represents the maximum compressive stress at the bottom section of the variable-diameter tower section. The radius of the top cross section of the variable diameter tower section; The radius of the bottom cross section of the variable diameter tower section; θ Angle in the circumferential direction; The wall thickness of the top section of the variable diameter tower section; The wall thickness of the bottom section of the variable diameter tower section;

[0026] Ignoring the weight of the ring wall portion, and for:

[0027] (3)

[0028] (4)

[0029] In the formula, For vertical loads; The bending moment; The area of ​​the top cross section; This represents the area of ​​the bottom cross-section; The top section modulus; The bottom section modulus;

[0030] Take the moment dM about the centroid of the top of the concrete ring, and the bending moment generated by the vertical load. Bending moment generated by horizontal load Horizontal load for:

[0031] (5)

[0032] (6)

[0033] (7)

[0034] In the formula, This refers to the height of the variable diameter tower section; It is a circumferential tensile force; For horizontal loads;

[0035] Depend on and Equilibrium yields:

[0036] (8)

[0037] Substituting equations (7), (2), and (4) into equation (8) above, we get:

[0038] (9)

[0039] If we consider the variable-diameter tower section as a thin-walled cylindrical structure, then the bottom cross-sectional area is... With bottom section modulus for:

[0040] (10)

[0041] (11)

[0042] In the formula, Let be the moment of inertia of the cross section about the neutral axis; This is the distance from the neutral axis to the outermost edge of the cross section;

[0043] because ,make Substituting into equation (9), the simplified formula for calculating the circumferential tensile force is:

[0044] (12).

[0045] In the above-mentioned design method for the concrete ring of the wind turbine, in steps 1-2, the circumferential tensile force is distributed according to the axial stiffness ratio of each component of the concrete ring, and the circumferential tensile force distributed to the UHPC layer is... Calculate using the following formula:

[0046] (13)

[0047] In the formula, The elastic modulus of the high-strength concrete core; This represents the stress-bearing area of ​​the high-strength concrete core. The elastic modulus of the circumferential reinforcing bar. The bearing area of ​​the circumferential reinforcing bars. The circumferential tension allocated to the UHPC layer, The elastic modulus of the UHPC layer. This represents the stress-bearing area of ​​the UHPC layer.

[0048] In the above design method for the concrete ring of the wind turbine, steps 1-3 do not consider the tensile properties of the high-strength concrete core, and the circumferential tensile force is entirely borne by the steel reinforcement and the UHPC layer. Therefore:

[0049] (14)

[0050] According to the stress formula:

[0051] (15)

[0052] In the formula, For stress, The internal force acting on the cross section, The cross-sectional area under the action of internal forces;

[0053] Then we have:

[0054] (16)

[0055] In the formula, For the stress of the UHPC layer, This represents the standard value of the tensile strength of the UHPC layer. UHPC layer thickness;

[0056] We can obtain:

[0057] (17)

[0058] In the above design method for the concrete ring sheet of the wind turbine, steps 1-4 first involve verifying the thickness of the UHPC layer:

[0059] (18)

[0060] In the formula, The thickness of the high-strength concrete core;

[0061] Then, calculations are performed to verify whether the high-strength concrete core cracks during operation:

[0062] (19)

[0063] In the formula, This refers to the stress in the high-strength concrete core. This refers to the standard value of the tensile strength of high-strength concrete core.

[0064] If cracks appear, the high-strength concrete core will be discontinued, and its tensile strength will no longer be considered.

[0065] The beneficial effects of this invention are as follows:

[0066] 1. The concrete ring of the present invention uses high-strength concrete as the load-bearing core and is covered with UHPC layers on the inner and outer sides. Relying on the excellent crack resistance of UHPC, it effectively inhibits the initiation and expansion of vertical cracks, ensuring the safe operation of the tower throughout its entire life cycle.

[0067] 2. The concrete ring sheet of the present invention uses UHPC layer only in key parts, which significantly improves the crack resistance of the variable diameter tower section, reduces the project cost, avoids the problem of excessive heat of hydration caused by excessive UHPC, effectively prevents the generation and development of through cracks, and comprehensively improves the stability, durability and economy of the structure.

[0068] 3. Based on the stress characteristics of the variable diameter tower section, this invention proposes a method for calculating the thickness of the UHPC layer. Specifically, the circumferential tensile force is calculated using a simplified stress model of the variable diameter tower section. Then, based on the deformation coordination principle, the circumferential tensile force is distributed according to the axial tensile stiffness to determine the circumferential tensile force on the UHPC layer. Finally, based on the standard value of the tensile strength of the UHPC layer, the minimum thin layer thickness that meets the crack resistance control is calculated, thereby obtaining the optimal concrete ring sheet, which makes the concrete ring sheet meet the usage requirements. Attached Figure Description

[0069] Figure 1 This is a schematic diagram of the structure of the variable diameter tower section.

[0070] Figure 2 This is a simplified diagram of the circumferential deformation of each ring plate in the variable diameter tower section.

[0071] Figure 3 This is a deformation cloud diagram of the variable diameter tower section.

[0072] Figure 4 This is a schematic diagram of the concrete ring structure of the present invention.

[0073] Figure 5 for Figure 4 Vertical cross-sectional view.

[0074] Figure 6 This is a flowchart of the design method of the present invention.

[0075] Figure 7 This is a simplified model diagram of a variable diameter tower section.

[0076] Figure 8 This is a schematic diagram of the analysis unit.

[0077] Figure 9 This is a diagram of the truss connection model for the analysis unit.

[0078] Figure 10 This is a schematic diagram of the circumferential tensile force in the analysis unit.

[0079] In the diagram, 1 is the variable diameter tower section, 2 is the concrete ring, 3 is the transverse joint, 4 is the longitudinal joint, 5 is the circumferential deformation inflection point, 6 is the high-strength concrete core, 7 is the UHPC layer, 8 is the tenon and mortise structure, and 9 is the reinforcing steel. Detailed Implementation

[0080] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0081] The tower consists of multiple tower sections, which are sequentially assembled to form the tower. Each tower section is composed of several concrete ring plates joined together. Figure 4 , Figure 5 As shown, a concrete ring for a wind turbine unit has a high-strength concrete core 6 in the center. The inner and outer walls of the ring are made of ultra-high performance concrete (UHPC) layers 7. The high-strength concrete core 6 and the UHPC layer 7 are joined by a tenon and mortise structure 8 and tightly connected by reinforcing bars 9 to form a whole. The UHPC layer 7 significantly enhances the circumferential crack resistance due to its high tensile strength, effectively suppressing the generation of vertical through cracks. At the same time, due to the protection of the UHPC layer 7, even if the high-strength concrete core 6 cracks after being subjected to tension, the reinforcing bars will not be corroded by external cracking and water seepage, ensuring the durability and safety of the structure.

[0082] A design method for concrete ring plates of wind turbine generators, such as Figure 6 As shown, it includes the following steps:

[0083] Step 1: Determine the thickness of the UHPC layer in the concrete ring according to the design load requirements of the tower section at the diameter change.

[0084] The process of determining the thickness of the UHPC layer in the concrete ring is as follows:

[0085] Step 1-1: Calculate the circumferential tensile force H using a simplified force model of the variable diameter tower section;

[0086] Step 1-2: Based on the deformation compatibility principle, the circumferential tensile force is distributed according to the axial tensile stiffness to determine the circumferential tensile force on the UHPC layer;

[0087] Steps 1-3: Based on the standard value of the tensile strength of the UHPC layer, calculate the minimum UHPC layer thickness that meets the crack resistance control requirements;

[0088] Steps 1-4: Verify the ultimate bearing capacity of the concrete ring and simultaneously check whether the high-strength concrete core has cracked.

[0089] The specific process of step 1-1 is as follows:

[0090] like Figures 6-10 As shown, the external load acting on the top of the variable diameter tower section is applied at the center of the top surface of the variable diameter tower section, with a circumferential width of [value missing]. dθ Force analysis of the tension / compression bar model is performed using narrow elements, and the equivalent compressive stress of the external load is applied to the centroid of the corresponding circular arc;

[0091] Analyze the vertical load at the top of the narrow element dP t and bottom vertical load dP b as follows:

[0092] (1)

[0093] (2)

[0094] In the formula, This represents the maximum compressive stress at the top section of the variable-diameter tower section; This represents the maximum compressive stress at the bottom section of the variable-diameter tower section. The radius of the top cross section of the variable diameter tower section; The radius of the bottom cross section of the variable diameter tower section; θ Angle in the circumferential direction; The wall thickness of the top section of the variable diameter tower section; The wall thickness of the bottom section of the variable diameter tower section;

[0095] The self-weight of the ring wall is not considered (the external load at the top and the tension of the steel strand are much greater than the self-weight of the ring wall). and for:

[0096] (3)

[0097] (4)

[0098] In the formula, For vertical loads; The bending moment; The area of ​​the top cross section; This represents the area of ​​the bottom cross-section; The top section modulus; The bottom section modulus;

[0099] Take the moment dM about the centroid of the top of the concrete ring, and the bending moment generated by the vertical load. Bending moment generated by horizontal load Horizontal load for:

[0100] (5)

[0101] (6)

[0102] (7)

[0103] In the formula, This refers to the height of the variable diameter tower section; It is a circumferential tensile force; For horizontal loads;

[0104] Depend on and Equilibrium yields:

[0105] (8)

[0106] Substituting equations (7), (2), and (4) into equation (8) above, and simplifying, we get:

[0107] (9)

[0108] Because the diameter of the tower section is much larger than its wall thickness, if the variable-diameter tower section is considered as a thin-walled cylindrical structure, then the bottom cross-sectional area is... With bottom section modulus for:

[0109] (10)

[0110] (11)

[0111] In the formula, Let be the moment of inertia of the cross section about the neutral axis; This is the distance from the neutral axis to the outermost edge of the cross section;

[0112] because ,make Substituting into equation (9), the simplified formula for calculating the circumferential tensile force is:

[0113] (12).

[0114] In steps 1-2, the circumferential tensile force is distributed according to the axial stiffness ratio of each component of the concrete ring, and the circumferential tensile force distributed to the UHPC layer is... Calculate using the following formula:

[0115] (13)

[0116] In the formula, The elastic modulus of the high-strength concrete core; This represents the stress-bearing area of ​​the high-strength concrete core. The elastic modulus of the circumferential reinforcing bar. The bearing area of ​​the circumferential reinforcing bars. The circumferential tension allocated to the UHPC layer, The elastic modulus of the UHPC layer. This represents the stress-bearing area of ​​the UHPC layer.

[0117] In steps 1-3, the tensile properties of the high-strength concrete core are not considered, and the circumferential tensile force is entirely borne by the reinforcing steel and the UHPC layer. Therefore:

[0118] (14)

[0119] According to the stress formula:

[0120] (15)

[0121] In the formula, For stress, The internal force acting on the cross section, The cross-sectional area under the action of internal forces;

[0122] Then we have:

[0123] (16)

[0124] In the formula, For the stress of the UHPC layer, This represents the standard value of the tensile strength of the UHPC layer. UHPC layer thickness;

[0125] We can obtain:

[0126] (17).

[0127] In steps 1-4, the thickness of the UHPC layer is first verified:

[0128] (18)

[0129] In the formula, The thickness of the high-strength concrete core;

[0130] Then, calculations are performed to verify whether the high-strength concrete core cracks during operation:

[0131] (19)

[0132] In the formula, This refers to the stress in the high-strength concrete core. This refers to the standard value of the tensile strength of high-strength concrete core.

[0133] If cracks appear, the high-strength concrete core will be discontinued, and its tensile strength will no longer be considered.

[0134] Step 2: Fabricate steel molds for the UHPC layers on the inner and outer walls of the concrete ring at the diameter change point;

[0135] Step 3: Pre-embed connecting steel bars, pour concrete for the UHPC layer components on the inner and outer walls of the ring, and cure.

[0136] Step 4: After the UHPC layer reaches the specified age requirement, use the UHPC layer as a template to carry out the inner layer reinforcement binding, high-strength concrete core pouring and curing.

[0137] Step 5: After the inner high-strength concrete core reaches the specified age, it is transported to the site for on-site hoisting and use.

[0138] This invention uses a concrete wind turbine tower as an example, with a hub height of 160m. This hybrid tower structure consists of a 132-meter-high concrete tower at the bottom and a 28-meter-high steel tower at the top, with the steel tower connecting the concrete tower to the wind turbine nacelle. The concrete tower is divided into 44 sections along its height, each section having a designed height of 3m. The circumferential reinforcing bars at the diameter transition sections use 18 HRB400 grade steel bars with a diameter of 32mm.

[0139] The parameters for UHPC layer thickness design are shown in Table 1. The thickness of the concrete ring is shown in Table 2; the data for the UHPC layer thickness verification are shown in Table 2.

[0140]

[0141]

[0142] The verification results show that the 50mm thick UHPC layer remained intact under vertical loads without cracking. Although the internal high-strength concrete core had cracked, the cracks could not penetrate to the structural surface due to the tight enclosure of the inner and outer UHPC layers. Therefore, even if the high-strength concrete core cracked under tension, external moisture could not penetrate, and the risk of steel corrosion was effectively controlled.

Claims

1. A design method for concrete ring plates of a wind turbine, wherein the tower comprises multiple tower sections, which are sequentially spliced ​​to form the tower. Each tower section is composed of several concrete ring plates spliced ​​together. The center of each concrete ring plate is a high-strength concrete core, and the inner and outer walls of the concrete ring plates are made of ultra-high performance concrete (UHPC) layers. The high-strength concrete core and the UHPC layer are spliced ​​together by mortise and tenon joints, and the UHPC layer and the high-strength concrete core are tightly connected by steel bars to form a whole. A tower section whose cross-sectional dimensions change in the height direction is defined as a variable-diameter tower section, and a tower segment containing a variable-diameter tower section is a variable-diameter tower segment, which is composed of the variable-diameter tower section and an adjacent lower tower section. The method is characterized in that... The design methodology includes the following steps: Step 1: Determine the thickness of the UHPC layer in the concrete ring according to the design load requirements of the tower section at the diameter change. In step one, the process of determining the thickness of the UHPC layer in the concrete ring is as follows: Step 1-1: Calculate the circumferential tension using a simplified force model of the variable diameter tower section. H ; The specific process of step 1-1 is as follows: The external load acting on the top of the reducing tower section is applied at the center of the top surface of the reducing tower section, with a circumferential width of [value missing]. dθ Force analysis of the tension / compression bar model is performed using narrow elements, and the equivalent compressive stress of the external load is applied to the centroid of the corresponding circular arc; Analyze the vertical load at the top of the narrow element dP t and bottom vertical load dP b as follows: （1）； （2）； In the formula, This represents the maximum compressive stress at the top section of the variable-diameter tower section; This represents the maximum compressive stress at the bottom section of the variable-diameter tower section. The radius of the top cross section of the variable diameter tower section; The radius of the bottom cross section of the variable diameter tower section; θ Angle in the circumferential direction; The wall thickness of the top section of the variable diameter tower section; The wall thickness of the bottom section of the variable diameter tower section; Ignoring the weight of the ring wall portion, and for: （3）； （4）； In the formula, For vertical loads; The bending moment; The area of ​​the top cross section; This represents the area of ​​the bottom cross-section; The top section modulus; The bottom section modulus; Take the moment dM about the centroid of the top of the concrete ring, and the bending moment generated by the vertical load. Bending moment generated by horizontal load Horizontal load for: （5）； （6）； （7）； In the formula, This refers to the height of the variable diameter tower section; It is a circumferential tensile force; For horizontal loads; Depend on and Equilibrium yields: （8）； Substituting equations (7), (2), and (4) into equation (8) above, and simplifying, we get: （9）； If we consider the variable-diameter tower section as a thin-walled cylindrical structure, then the bottom cross-sectional area is... With bottom section modulus for: （10）； （11）； In the formula, Let be the moment of inertia of the cross section about the neutral axis; This is the distance from the neutral axis to the outermost edge of the cross section; because ,make Substituting into equation (9), the simplified formula for calculating the circumferential tensile force is: （12）； Step 1-2: Based on the deformation compatibility principle, the circumferential tensile force is distributed according to the axial tensile stiffness to determine the circumferential tensile force on the UHPC layer; Steps 1-3: Based on the standard value of the tensile strength of the UHPC layer, calculate the minimum UHPC layer thickness that meets the crack resistance control requirements; Steps 1-4: Verify the ultimate bearing capacity of the concrete ring and simultaneously check whether the high-strength concrete core has cracked. Step 2: Fabricate steel molds for the UHPC layers on the inner and outer walls of the concrete ring at the diameter change point; Step 3: Pre-embed connecting steel bars, pour concrete for the UHPC layer components on the inner and outer walls of the ring, and cure. Step 4: After the UHPC layer reaches the specified age requirement, use the UHPC layer as a template to carry out the inner layer reinforcement binding, high-strength concrete core pouring and curing. Step 5: After the inner high-strength concrete core reaches the specified age, it is transported to the site for on-site hoisting and use.

2. The design method for concrete ring plates of wind turbine generators according to claim 1, characterized in that, In steps 1-2, the circumferential tensile force is distributed according to the axial stiffness ratio of each component of the concrete ring, and the circumferential tensile force distributed to the UHPC layer is... Calculate using the following formula: （13）； In the formula, The elastic modulus of the high-strength concrete core; This represents the stress-bearing area of ​​the high-strength concrete core. The elastic modulus of the circumferential reinforcing bar. The bearing area of ​​the circumferential reinforcing bars. The circumferential tension allocated to the UHPC layer, The elastic modulus of the UHPC layer. This represents the stress-bearing area of ​​the UHPC layer.

3. The design method for concrete ring plates of wind turbine units according to claim 2, characterized in that, In steps 1-3, the tensile properties of the high-strength concrete core are not considered, and the circumferential tensile force is entirely borne by the reinforcing steel and the UHPC layer. Therefore: （14）； According to the stress formula: （15）； In the formula, For stress, The internal force acting on the cross section, Let be the cross-sectional area under the action of internal forces; then we have: （16）； In the formula, For the stress of the UHPC layer, This represents the standard value of the tensile strength of the UHPC layer. UHPC layer thickness; We can obtain: （17）。 4. The design method for concrete ring plates of wind turbine generators according to claim 3, characterized in that, In steps 1-4, the thickness of the UHPC layer is first verified: （18）； In the formula, The thickness of the high-strength concrete core; Then, calculations are performed to verify whether the high-strength concrete core cracks during operation: （19）； In the formula, This refers to the stress in the high-strength concrete core. This refers to the standard value of the tensile strength of high-strength concrete core. If cracks appear, the high-strength concrete core will be discontinued, and its tensile strength will no longer be considered.

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