Prefabricated assembly beam-slab foundation, assembling method and design method

Abstract

The application relates to the technical field of wind power equipment, and discloses a prefabricated assembly type beam-slab foundation, an assembling method and a design method, which comprise an upper ring body prefabricated component, a lower ring body prefabricated component, a first anchor bolt assembly, a second anchor bolt assembly and a plurality of foundation prefabricated components; the lower ring body prefabricated component is arranged on a foundation cushion layer; the foundation prefabricated components are sequentially assembled on the top of the lower ring body prefabricated component in a ring direction; and the upper ring body prefabricated component is arranged on the top of the plurality of foundation prefabricated components; the lower end of each foundation prefabricated component is provided with a stepped gap; the upper surface and the outer circumferential surface of the lower ring body prefabricated component are matched with horizontal matching surfaces and vertical matching surfaces respectively to realize self-positioning; filling materials are filled in the assembling joints between the components; the first anchor bolt assembly is arranged between the upper ring body prefabricated component and the foundation prefabricated component; and the second anchor bolt assembly is arranged between the lower ring body prefabricated component and the foundation prefabricated component. The application can solve the technical problem of low construction efficiency caused by cast-in-place construction of the existing steel-concrete tower foundation.

Description

Technical Field

[0001] This invention relates to the field of wind power equipment technology, specifically to a prefabricated assembled beam-slab foundation, assembly method, and design method. Background Technology

[0002] Onshore wind power is the core component of newly installed wind power capacity in my country, accounting for over 90% of the total annual new installations. Onshore wind turbine towers are mainly divided into two structural forms: steel towers and reinforced concrete towers. Among them, reinforced concrete towers, with their advantages of high structural rigidity, controllable material costs, and adaptability to the needs of tall towers, have achieved an industry penetration rate of around 40% and are showing a continuous upward trend, becoming the mainstream development direction in the onshore wind turbine tower field.

[0003] Currently, cast-in-place construction is commonly used for the steel-concrete tower foundations of onshore wind turbines. However, this method has the following technical drawbacks: the volume of concrete for a conventional cast-in-place foundation is approximately 1000 m³. 3 This requires 100 to 120 truckloads of ready-mixed concrete transportation, placing high demands on the road transport conditions of the wind farm. Furthermore, the on-site pouring and curing of large-volume concrete is constrained by environmental temperature, humidity, and construction continuity, making the foundation prone to quality defects such as construction cold joints, temperature cracks, and internal cavities, affecting the long-term safety and durability of the wind turbine foundation. In addition, the cast-in-place process is difficult to implement in low-temperature environments, making it difficult to meet winter construction requirements. These issues hinder the efficient and high-quality construction of wind farms.

[0004] Compared to cast-in-place foundations, precast foundations allow for standardized prefabrication of components in factories, ensuring controllable product quality. On-site assembly is minimal, significantly improving construction efficiency and effectively avoiding the aforementioned technical challenges of cast-in-place construction. However, current research, both domestically and internationally, on structural designs and technical systems for precast foundations compatible with reinforced concrete towers lacks systematic exploration, creating a clear technological gap. There is an urgent need to develop a precast foundation solution that is structurally sound, easy to construct, and compatible with reinforced concrete towers. Summary of the Invention

[0005] The purpose of this invention is to provide a prefabricated assembled beam-slab foundation, assembly method, and design method to solve the technical problems of difficult quality control, low construction efficiency, and difficulty in winter construction caused by the existing cast-in-place construction process for reinforced concrete tower foundations.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0007] In a first aspect, the present invention provides a precast precast beam-slab foundation, comprising an upper ring precast component, a lower ring precast component, a first anchor bolt assembly, a second anchor bolt assembly, and multiple foundation precast components; the lower ring precast component is disposed on a foundation pad layer, and the multiple foundation precast components are sequentially assembled circumferentially on top of the lower ring precast component, and the upper ring precast component is disposed on top of the multiple foundation precast components; the lower end of the foundation precast component near the lower ring precast component is provided with a stepped notch, and the horizontal mating surface of the stepped notch is mated with the upper surface of the lower ring precast component. The vertical mating surface of the stepped notch mates with the outer peripheral surface of the lower ring precast component; the lower surface of the upper ring precast component mates with the upper surface of the foundation precast component; the assembly joints formed between two adjacent foundation precast components, between the lower ring precast component and the foundation precast component, and between the upper ring precast component and the foundation precast component are filled with filling material; the first anchor bolt assembly passes through the upper ring precast component and the foundation precast component; the second anchor bolt assembly passes through the lower ring precast component and the foundation precast component.

[0008] In one embodiment, the system further includes a circumferential prestressing component, which is arranged circumferentially around a plurality of the foundation prefabricated components.

[0009] In one embodiment, the system further includes a tower prestressing assembly. The lower ring precast component, the foundation precast component, and the upper ring precast component each have pre-drilled mounting holes for the tower prestressing assembly to pass through. The tower prestressing assembly passes through the upper ring precast component, the foundation precast component, and the lower ring precast component sequentially from top to bottom. After tensioning, a vertical contraction and tightening force is applied to the upper ring precast component and the lower ring precast component, causing a relative tightening tendency between them. This clamps and secures the foundation precast component located between the upper ring precast component and the lower ring precast component, thus constraining the vertical relative displacement between the precast components.

[0010] In one embodiment, the lower surface of the upper ring prefabricated component is provided with a protrusion along the circumferential direction, and the upper surface of the foundation prefabricated component is provided with a groove that matches the protrusion.

[0011] In one embodiment, the prefabricated foundation components include columns, a base plate, and ribs. The columns are arranged vertically, and their horizontal projections are fan-shaped. When multiple prefabricated foundation components are assembled into a ring along the circumferential direction, the horizontal projections of the fan-shaped components of each column are sequentially assembled to form a complete ring. The central angle of the fan-shaped component corresponds to the number of segments in the circumferential direction. The top surface of the column mates with the lower surface of the upper ring prefabricated component, and the bottom end of the column is provided with an inverted L-shaped notch for positioning and engaging with the lower ring prefabricated component. The base plate is arranged horizontally on the outer side of the bottom end of the column, and the bottom surface of the base plate mates with the foundation pad. The ribs are right-angled triangular plates, with one right-angled side connected to the outer side of the column and the other right-angled side connected to the upper surface of the base plate. The ribs, columns, and base plate are integrally cast and formed to enclose a triangular stiffening structure.

[0012] In one embodiment, both the upper and lower ring precast components are formed by sequentially splicing and enclosing several arc-shaped precast blocks evenly distributed along the circumferential direction to form a complete ring. Adjacent arc-shaped precast blocks are welded together by pre-embedded connecting nail steel plate assemblies. The pre-embedded connecting nail steel plate assembly includes a steel plate and several connecting nails disposed on one side of the steel plate. The connecting nails are anchored in the concrete of the corresponding arc-shaped precast block. The surface of the steel plate is exposed at the circumferential joint end face of the arc-shaped precast block. The steel plates of two adjacent arc-shaped precast blocks are welded and fixed at the circumferential joint end face.

[0013] In one embodiment, the first anchor bolt assembly penetrates vertically through the upper ring precast component and the foundation precast component to fix the upper ring precast component and the foundation precast component together; the second anchor bolt assembly penetrates horizontally through the lower ring precast component and the foundation precast component to fix the lower ring precast component and the foundation precast component together.

[0014] Secondly, the present invention provides a method for assembling a prefabricated beam-slab foundation, comprising:

[0015] S1. Pouring the foundation pad layer;

[0016] S2. Lay a sand layer on the top surface of the foundation pad layer and at the preset installation position corresponding to the foundation prefabricated component;

[0017] S3. Hoist the prefabricated lower ring component into place;

[0018] S4. Apply filling material to the assembly joints between the lower ring prefabricated component and each of the foundation prefabricated components, as well as the assembly joints between two adjacent foundation prefabricated components. Then, hoist each of the foundation prefabricated components to the top of the lower ring prefabricated component in sequence along the circumferential direction, so that the horizontal mating surface of the stepped notch mates with the upper surface of the lower ring prefabricated component, and the vertical mating surface of the stepped notch mates with the outer peripheral surface of the lower ring prefabricated component.

[0019] S5. Apply filling material to the assembly joint between the upper ring prefabricated component and each of the foundation prefabricated components, and then hoist the upper ring prefabricated component to the top of each of the foundation prefabricated components so that the lower surface of the upper ring prefabricated component matches the upper surface of the foundation prefabricated component.

[0020] S6. Install the first anchor bolt assembly, the second anchor bolt assembly, and the circumferential prestressed assembly, such that the first anchor bolt assembly passes through the upper ring precast component and the foundation precast component, and the second anchor bolt assembly passes through the lower ring precast component and the foundation precast component;

[0021] S7. Install the steel-concrete tower on the upper ring prefabricated component, and install and tension the tower prestressing components of the steel-concrete tower.

[0022] In one embodiment, both the upper ring prefabricated component and the lower ring prefabricated component are formed by sequentially splicing and enclosing several arc-shaped prefabricated blocks evenly distributed along the circumferential direction to form a complete ring.

[0023] The assembly method further includes, before step S3: sequentially splicing several of the arc-shaped prefabricated blocks along the circumferential direction, such that the end faces of the steel plates of adjacent arc-shaped prefabricated blocks abut against each other at the circumferential joint end faces, and welding and fixing the abutting steel plates to form the lower ring prefabricated component.

[0024] The assembly method further includes, after step S5, the following steps: sequentially splicing several of the arc-shaped prefabricated blocks along the circumferential direction, such that the end faces of the steel plates of adjacent arc-shaped prefabricated blocks abut against each other at the circumferential joint end faces, and welding and fixing the abutting steel plates to form the upper ring prefabricated component.

[0025] Thirdly, the present invention provides a design method for prefabricated assembled beam-slab foundations, which includes the following steps:

[0026] Step 1: Based on the initial structural parameters, the design loads acting on the tower and the prefabricated assembled beam and slab foundation are calculated by using a coupled solution method of aerodynamic load and structural dynamics.

[0027] Step 2: Based on the design load, perform structural design and performance verification on the tower structure and the prefabricated assembled beam-slab foundation respectively to obtain updated structural parameters and foundation stiffness.

[0028] Step 3: Based on the updated structural parameters and foundation stiffness, recalculate the design load and verify the overall frequency of the machine.

[0029] Step 4: Determine if the following convergence conditions are met simultaneously:

[0030] The inherent frequency of the entire machine is within the preset range;

[0031] The strength, fatigue, and prestress calculations of the tower structure meet the design criteria.

[0032] The overall stability, strength, fatigue, and connection node strength of the precast assembled beam-slab foundation meet the design criteria.

[0033] If all conditions are met, the final structural design scheme is output; if any condition is not met, return to step three and continue iterating until all convergence conditions are met.

[0034] The present invention has the following unexpected beneficial effects:

[0035] 1. The precast upper ring component, lower ring component, and foundation component of this invention can be produced in a standardized factory, with controllable concrete pouring, vibration, and curing conditions, fundamentally avoiding quality defects such as construction cold joints, temperature cracks, and internal cavities in cast-in-place foundations. On-site work only requires dry operations such as component hoisting, joint filling, and anchor bolt installation, significantly reducing on-site wet work and the need for transporting ready-mixed concrete, thus significantly shortening the construction cycle. Furthermore, the foundation precast component base plate sits directly on the foundation pad, eliminating the need for grouting and avoiding the problem of grouting material difficulty in setting and hardening at low temperatures, effectively extending the workable window.

[0036] 2. The stepped notch at the lower end of the precast foundation component of the present invention achieves vertical positioning and radial positioning through the horizontal mating surface and the vertical mating surface, respectively, so that the component can automatically complete bidirectional positioning when it is hoisted and placed, without the need for additional positioning fixtures; the protrusion on the lower surface of the upper ring precast component is adapted to the groove on the upper surface of the foundation precast component, achieving circumferential positioning during assembly, and transmitting horizontal shear force through side contact when under stress, preventing relative slippage.

[0037] 3. The circumferential prestressed component of this invention applies circumferential prestress to the precast foundation components assembled into a ring, ensuring that each segment fits tightly and shares the load collaboratively. The first and second anchor bolt assemblies respectively fix the upper and lower ring precast components to the foundation precast components, forming a complete force transmission path. The columns, base plate, and ribs in the foundation precast components are integrally cast to form a triangular stiffening structure, fully utilizing the geometric invariance of triangles to significantly improve the bending stiffness and shear bearing capacity of the components, ensuring that the overall performance of the assembled foundation meets the load transfer requirements of the reinforced concrete tower.

[0038] 4. The upper and lower ring prefabricated components of the present invention are both spliced ​​together along the circumferential direction by several arc-shaped prefabricated blocks and welded together by pre-embedded connecting nail steel plate assemblies to form a complete ring. This not only solves the problem of difficult overall transportation of large-diameter ring components, but also achieves reliable connection of circumferential joints through steel plate welding and anchoring with connecting nails, so that the assembled ring has structural performance comparable to that of a cast-in-place ring. Attached Figure Description

[0039] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention.

[0040] Figure 1 A cross-sectional view of the prefabricated assembled beam-slab foundation disclosed in this invention is shown.

[0041] Figure 2 A top view of the prefabricated assembled beam-slab foundation disclosed in this invention is shown.

[0042] Figure 3 A cross-sectional view of the prefabricated upper ring component disclosed in this invention is shown.

[0043] Figure 4 A top view of the prefabricated upper ring component disclosed in this invention is shown.

[0044] Figure 5 A cross-sectional view of the prefabricated upper ring component disclosed in this invention is shown.

[0045] Figure 6 A top view of the prefabricated upper ring component disclosed in this invention is shown.

[0046] Figure 7 A schematic diagram of the pre-embedded connecting nail steel plate assembly disclosed in this invention is shown.

[0047] Figure 8 A cross-sectional view of the prefabricated basic component disclosed in this invention is shown.

[0048] Figure 9A top view of the prefabricated basic component disclosed in this invention is shown.

[0049] Figure 10 A flowchart illustrating the assembly method of the prefabricated assembled beam-slab foundation disclosed in this invention is shown.

[0050] Explanation of reference numerals in the attached figures:

[0051] 100 - Upper ring prefabricated component, 101 - Protrusion, 102 - First mounting hole, 103 - Second mounting hole.

[0052] 110 - Lower ring prefabricated component, 111 - Third mounting hole, 112 - Fourth mounting hole

[0053] 200 - First Anchor Bolt Assembly

[0054] 210 - Second Anchor Bolt Assembly

[0055] 300 - Precast foundation component; 310 - Stepped notch; 311 - Horizontal mating surface; 312 - Vertical mating surface; 320 - Groove; 330 - Column; 331 - Fifth mounting hole; 332 - Sixth mounting hole; 333 - Seventh mounting hole; 334 - Limiting groove; 340 - Base plate; 350 - Rib beam

[0056] 400-Assembly seam,

[0057] 500-Circumferential Prestressed Assembly

[0058] 600-Tower prestressed assembly,

[0059] 700 - Embedded connecting nail steel plate assembly, 710 - Steel plate, 720 - Connecting nail

[0060] 800 - base layer, 810 - sand layer

[0061] 900-Reinforced concrete tower. Detailed Implementation

[0062] The embodiments of the present invention will be described below with reference to the accompanying drawings and preferred embodiments. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be understood that the preferred embodiments are only for illustrating the present invention and not for limiting the scope of protection of the present invention.

[0063] It should be noted that the illustrations provided in the following embodiments are only schematic representations of the basic concept of the present invention. The drawings only show the components related to the present invention and are not drawn according to the actual number, shape and size of the components in the actual implementation. In the actual implementation, the form, quantity and proportion of each component can be arbitrarily changed, and the layout of the components may also be more complex.

[0064] The embodiments of the present invention will be described below with reference to the accompanying drawings and preferred embodiments. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be understood that the preferred embodiments are only for illustrating the present invention and not for limiting the scope of protection of the present invention.

[0065] It should be noted that the illustrations provided in the following embodiments are only schematic representations of the basic concept of the present invention. The drawings only show the components related to the present invention and are not drawn according to the actual number, shape and size of the components in the actual implementation. In the actual implementation, the form, quantity and proportion of each component can be arbitrarily changed, and the layout of the components may also be more complex.

[0066] In the description of this invention, it should be understood that the terms "upper", "lower", "inner", "outer", "circumferential", "radial", "vertical", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting this invention.

[0067] In one embodiment, reference is made to Figure 1 and Figure 2 This embodiment provides a prefabricated assembled beam-slab foundation, including an upper ring prefabricated component 100, a lower ring prefabricated component 110, a first anchor bolt assembly 200, a second anchor bolt assembly 210, and multiple foundation prefabricated components 300.

[0068] The lower ring precast component 110 is placed on top of the foundation pad 800. Multiple foundation precast components 300 are sequentially assembled circumferentially on top of the lower ring precast component 110. The upper ring precast component 100 is placed on top of the multiple foundation precast components 300. Thus, the lower ring precast component 110, the multiple foundation precast components 300, and the upper ring precast component 100 are stacked sequentially from bottom to top, together forming the main structure of the precast assembled beam-slab foundation.

[0069] The foundation precast component 300 has a stepped notch 310 at its lower end near the lower ring precast component 110. The horizontal mating surface 311 of the stepped notch 310 mates with the upper surface of the lower ring precast component 110, and the vertical mating surface 312 of the stepped notch 310 mates with the outer circumferential surface of the lower ring precast component 110. Through the bidirectional mating of the horizontal mating surface 311 and the vertical mating surface 312, the foundation precast component 300 can automatically complete vertical and radial positioning during hoisting and placement, without the need for additional positioning tools or measurement adjustments. This reduces the construction difficulty and cumulative error of on-site assembly and ensures the circumferential assembly accuracy.

[0070] The lower surface of the upper ring precast component 100 mates with the upper surface of the foundation precast component 300 to achieve vertical support and load transfer between the upper ring precast component 100 and the foundation precast component 300.

[0071] The assembly joints 400 formed between two adjacent precast foundation components 300, between the lower ring precast component 110 and the precast foundation component 300, and between the upper ring precast component 100 and the precast foundation component 300 are filled with a filling material. The filling material can be high-strength non-shrink grout, epoxy resin mortar, or polymer cement mortar, etc., used to fill the gaps in the assembly joints 400, ensuring continuous force transmission between components, dense contact surfaces, and preventing moisture and debris from entering the interior of the assembly joints 400.

[0072] The first anchor bolt assembly 200 is inserted between the upper ring precast component 100 and the foundation precast component 300, fixing them in place. The second anchor bolt assembly 210 is inserted between the lower ring precast component 110 and the foundation precast component 300, fixing them in place. The first anchor bolt assembly 200 and the second anchor bolt assembly 210 work together to form a reliable force transmission path of "upper ring precast component 100—foundation precast component 300—lower ring precast component 110", ensuring that the precast components work together without relative displacement under the wind turbine operating load.

[0073] This embodiment divides the foundation into an upper ring precast component 100, a lower ring precast component 110, and multiple foundation precast components 300. All components are precast in a standardized factory, ensuring controllable concrete pouring, vibration, and curing conditions. This fundamentally avoids quality defects such as construction cold joints, temperature cracks, and internal cavities that occur in cast-in-place foundations due to large-volume concrete pouring on-site. On-site work only requires dry operations such as component hoisting, filling the assembly joints 400, and anchor bolt installation, significantly reducing on-site wet work and the need for transporting commercial concrete, thus significantly shortening the construction cycle. The bidirectional self-positioning of the stepped notch 310 reduces construction difficulty, while the first anchor bolt assembly 200 and the second anchor bolt assembly 210 ensure the integrity and reliable force transmission of the assembled structure.

[0074] As an optional implementation of this application, see [link to relevant documentation]. Figure 1 As shown, the precast assembled beam-slab foundation of this embodiment also includes a circumferential prestressed component 500. The circumferential prestressed component 500 is arranged circumferentially around multiple foundation precast components 300.

[0075] Specifically, the circumferential prestressed component 500 can be made of prestressed steel strands, prestressed steel wires, or prestressed steel bars, and is arranged around the circumferential outer side of the foundation precast component 300 or within the reserved duct. Circumferential prestress is applied to the assembled ring of multiple foundation precast components 300 through tension anchoring. The circumferential prestress ensures a tight fit between the individual foundation precast components 300, and the assembly joint 400 is under compression. This effectively improves the overall stiffness and crack resistance of the assembled foundation under wind turbine operating loads, and prevents the assembly joint 400 from opening or slipping under alternating loads.

[0076] For example, see Figure 1 and Figure 8 As shown, the outer circumferential surface of the column 330 of the foundation precast component 300 is provided with a plurality of limiting grooves 334 that are adapted to the circumferential prestressed component 500.

[0077] The circumferential prestressed component 500 applies circumferential prestress to the precast foundation component 300 assembled into a ring, so that each segment fits tightly and shares the load. Together with the first anchor bolt component 200 and the second anchor bolt component 210, it forms a complete connection and force transmission system, so that the overall stiffness and bearing capacity of the foundation after segment assembly meet the load transmission requirements of the steel-concrete tower 900.

[0078] As an optional implementation of this application, see [link to relevant documentation]. Figure 1 As shown, the precast assembled beam-slab foundation of this embodiment also includes a tower prestressing assembly 600. The lower ring precast component 110, the foundation precast component 300, and the upper ring precast component 100 each have pre-drilled mounting holes for the tower prestressing assembly 600 to pass through. The tower prestressing assembly 600 passes through the upper ring precast component 100, the foundation precast component 300, and the lower ring precast component 110 sequentially from top to bottom. After tensioning, a vertical contraction and tightening force is applied to the upper ring precast component 100 and the lower ring precast component 110, causing a relative tightening tendency between them. This clamps and secures the foundation precast component 300 located between the upper ring precast component 100 and the lower ring precast component 110, constraining the vertical relative displacement between the precast components.

[0079] Specifically, the upper ring precast component 100 has a second mounting hole 103, the lower ring precast component 110 has a fourth mounting hole 112, and the foundation precast component 300's column 330 has a seventh mounting hole 333. The tower prestressed assembly 600 passes through the second mounting hole 103, the seventh mounting hole 333, and the fourth mounting hole 112 sequentially from top to bottom, and is vertically prestressed into a single unit by tension anchoring of the upper ring precast component 100, the foundation precast component 300, and the lower ring precast component 110. The column 330 also has a clearance hole 334 for avoiding other components or pipelines.

[0080] The tower prestressed component 600 can use prestressed steel strands or prestressed threaded steel bars, etc. Its vertical prestress keeps the contact surfaces between the precast components of each layer in a compressed state, which enhances the overall foundation's resistance to overturning and pull-out under the action of the wind turbine overturning moment.

[0081] The tower prestressed component 600 is inserted into each layer of precast components through reserved installation holes, and prestress is applied vertically to prestress the upper ring precast component 100, the foundation precast component 300 and the lower ring precast component 110 into a whole, which enhances the overall stability and crack resistance of the foundation under the action of wind turbine overturning bending moment and vertical pull force, and ensures a reliable connection between the steel-concrete tower 900 and the foundation.

[0082] As an optional embodiment of this application, the mating structure between the upper ring prefabricated component 100 and the foundation prefabricated component 300 is further defined.

[0083] Reference Figure 3 and Figure 4 As shown, the lower surface of the upper ring prefabricated component 100 is provided with a protrusion 101 along the circumferential direction. The upper surface of the foundation prefabricated component 300 is provided with a groove 320 that matches the protrusion 101. The protrusion 101 and the groove 320 extend along the circumferential direction and fit together during assembly.

[0084] During assembly, the protrusion 101 is embedded in the groove 320, achieving circumferential positioning between the upper ring precast component 100 and the foundation precast component 300, preventing relative rotation between the two in the circumferential direction. Under stress, the side of the protrusion 101 abuts against the side of the groove 320, transmitting horizontal shear force through lateral bearing pressure, preventing relative slippage between the upper ring precast component 100 and the foundation precast component 300 under horizontal load, and enhancing the shear resistance between the two.

[0085] The fitting of the protrusion 101 and the groove 320 has both positioning and shear resistance functions. It achieves precise circumferential positioning during assembly and transmits horizontal shear force through side contact when under stress, effectively preventing relative slippage between the upper ring precast component 100 and the foundation precast component 300, thereby improving the shear bearing capacity and positioning accuracy of the assembly node.

[0086] As an optional implementation of this application, this embodiment further defines the specific structure of the foundation prefabricated component 300.

[0087] Reference Figure 8 and Figure 9 As shown, the foundation precast component 300 includes a column 330, a base plate 340, and a rib beam 350.

[0088] The columns 330 are vertically arranged, and their horizontal projections are fan-shaped. When multiple foundation prefabricated components 300 are assembled into a ring along the circumference, the fan-shaped horizontal projections of each column 330 are sequentially combined to form a complete ring, with the central angle of the fan corresponding to the number of circumferential segments. For example, when the number of circumferential segments is 8, the central angle of the fan corresponding to the column 330 of each foundation prefabricated component 300 is 45°; when the number of circumferential segments is 12, the corresponding central angle of the fan is 30°. The top surface of the column 330 mates with the lower surface of the upper ring prefabricated component 100 to receive and transmit the vertical loads and bending moments from the upper ring prefabricated component 100.

[0089] The bottom end of the column 330 is provided with a stepped notch 310 for positioning and engaging with the precast lower ring component 110. The horizontal mating surface 311 of the stepped notch 310 engages with the upper surface of the precast lower ring component 110 to achieve vertical positioning, and the vertical mating surface 312 of the stepped notch 310 engages with the outer circumferential surface of the precast lower ring component 110 to achieve radial positioning.

[0090] The base plate 340 is horizontally positioned on the outer side of the bottom end of the column 330. The bottom surface of the base plate 340 mates with the foundation pad 800 to distribute and transfer the load borne by the precast foundation component 300 to the foundation pad 800. The base plate 340 rests directly on the foundation pad 800 or on the sand layer 810 on top of the foundation pad 800, without the need for grouting between the base plate 340 and the foundation pad 800.

[0091] The rib beam 350 is a right-angled triangular plate, with one right-angled side connected to the outer surface of the pedestal 330 and the other right-angled side connected to the upper surface of the base plate 340. The rib beam 350, pedestal 330, and base plate 340 are integrally cast and formed to enclose a triangular stiffening structure. This triangular stiffening structure makes full use of the geometric invariance of triangles to form a rigid connection between the pedestal 330 and the base plate 340, significantly improving the bending stiffness and shear bearing capacity of the foundation precast component 300. This allows the vertical load and bending moment from the top of the pedestal 330 to be efficiently transferred to the base plate 340 through the rib beam 350, and then diffused from the base plate 340 to the foundation pad 800. The load transfer path is clear and the stress distribution is reasonable.

[0092] The column 330, base plate 340 and rib beam 350 are cast together to form a triangular stiffened structure. The components have high rigidity and efficient force transmission. By making full use of the geometric invariance of triangles, the bending stiffness and shear bearing capacity are significantly improved. The base plate 340 sits directly on the foundation pad 800, without the need for base plate grouting. This avoids the problem of grouting material having difficulty setting and hardening in low temperature environments, effectively extending the construction window and freeing the foundation construction from the strict constraints of low temperature conditions in winter.

[0093] As an optional implementation of this application, this embodiment further defines the specific structure of the upper ring prefabricated component 100 and the lower ring prefabricated component 110.

[0094] Reference Figures 3 to 7 Both the upper ring precast component 100 and the lower ring precast component 110 are formed by sequentially splicing and enclosing several arc-shaped precast blocks evenly distributed along the circumference to form a complete ring. Adjacent arc-shaped precast blocks are welded together by pre-embedded connecting nail steel plate assemblies 700.

[0095] The pre-embedded connecting nail steel plate assembly 700 includes a steel plate 710 and a plurality of connecting nails 720 disposed on one side of the steel plate 710. The connecting nails 720 are anchored in the concrete of the corresponding arc-shaped precast block, and the surface of the steel plate 710 is exposed at the circumferential joint end face of the arc-shaped precast block. The steel plates 710 of two adjacent arc-shaped precast blocks are welded and fixed at the circumferential joint end face, thereby achieving a reliable connection between adjacent arc-shaped precast blocks.

[0096] Specifically, the connecting studs 720 can be studs, hooked reinforcing bars, or corrugated anchor bars, which are anchored in the concrete of the curved precast block to ensure a reliable connection between the steel plate 710 and the curved precast block body. The portion of the steel plate 710 exposed at the end face of the circumferential joint is used for butt welding or lap welding with the steel plates 710 of adjacent curved precast blocks. After welding, the circumferential joint forms a reliable rigid connection.

[0097] The upper ring precast component 100 and the lower ring precast component 110 are precast in sections using arc-shaped precast blocks and assembled and welded on site. The size and weight of each arc-shaped precast block are controllable, facilitating factory production, transportation, and on-site hoisting. The complete ring formed after assembly and welding has structural stiffness and load-bearing capacity comparable to that of a monolithic cast ring.

[0098] The upper ring precast component 100 and the lower ring precast component 110 are precast in sections with arc-shaped precast blocks and assembled and welded on site. This not only solves the problem of difficult overall transportation of large-diameter ring components, but also achieves reliable connection of circumferential joints through welding of steel plates 710 and anchoring with connecting nails 720. This gives the assembled ring a structural performance comparable to that of a cast-in-place ring, taking into account both transportation convenience and structural integrity.

[0099] As an optional implementation of this application, see [link to relevant documentation]. Figure 1 As shown, this embodiment further defines the insertion direction of the first anchor bolt assembly 200 and the second anchor bolt assembly 210.

[0100] The first anchor bolt assembly 200 penetrates vertically through the upper ring precast component 100 and the foundation precast component 300 to fix the upper ring precast component 100 and the foundation precast component 300 together. Specifically, the first anchor bolt assembly 200 passes through the first mounting hole 102 in the upper ring precast component 100 and the fifth mounting hole 331 in the column 330 of the foundation precast component 300 from top to bottom, and the vertical fixed connection between the upper ring precast component 100 and the foundation precast component 300 is achieved by tightening with nuts.

[0101] The second anchor bolt assembly 210 passes horizontally through the lower ring precast component 110 and the foundation precast component 300 to fix the lower ring precast component 110 and the foundation precast component 300 together. Specifically, the second anchor bolt assembly 210 passes radially horizontally through the third mounting hole 111 in the lower ring precast component 110 and the sixth mounting hole 332 on the side wall of the foundation precast component 300 column 330, and the horizontal fixed connection between the lower ring precast component 110 and the foundation precast component 300 is achieved by tightening with a nut.

[0102] The first anchor bolt assembly 200 is installed vertically and mainly bears the vertical shear and pull-out forces between the upper ring precast component 100 and the foundation precast component 300. The second anchor bolt assembly 210 is installed horizontally and mainly bears the radial shear force between the lower ring precast component 110 and the foundation precast component 300. Their different directions and clear division of forces ensure a reliable connection between the components of the assembled foundation.

[0103] The first anchor bolt assembly 200 is installed vertically and the second anchor bolt assembly 210 is installed horizontally. The two are orthogonal and have a clear division of forces. They reliably connect the prefabricated components from both vertical and radial dimensions to form a complete spatial force transmission system, ensuring the overall stability of the assembled foundation under the multi-directional load of the wind turbine.

[0104] Furthermore, this embodiment provides a detailed description of the collaborative load-bearing mechanism between the steel-concrete tower 900 and the prefabricated assembled beam-slab foundation.

[0105] The reinforced concrete tower 900 is not a monolithic structure, but rather a tower structure formed by vertically accumulating multiple ring-shaped precast segments with heights ranging from 2m to 3.5m, layer by layer, up to a height of over 100 meters. No bolts or other mechanical connections are used between adjacent layers of ring-shaped precast segments; instead, they are connected by several bundles of tower prestressing components 600 extending from the top of the tower to the bottom of the foundation. After tensioning, the tower prestressing components 600 apply a meganewton-level preload, vertically clamping and securing each layer of ring-shaped precast segments to the foundation, thus forming a continuous prestressed stress system for the entire tower.

[0106] In existing prefabricated foundation schemes adapted to steel-concrete towers, the foundation structure does not make full use of the clamping prestressing force provided by the prestressing system of the steel-concrete tower 900 itself. Instead, it is necessary to design additional connection structures to resist or offset the adverse effects of the prestressing force on the foundation components, resulting in increased structural redundancy, increased material usage, and increased construction costs.

[0107] In this embodiment, the prefabricated beam-slab foundation utilizes an upper ring prefabricated component 100, a lower ring prefabricated component 110, and an irregularly shaped foundation prefabricated component 300 with an inverted L-shaped stepped notch 310 and a concave structure. This allows the upper ring prefabricated component 100, the lower ring prefabricated component 110, and the foundation prefabricated component 300 to fit tightly together. After on-site assembly, the upper ring prefabricated component 100 and the lower ring prefabricated component 110 form complete circumferential integral structures. When the tower prestressing assembly 600 of the reinforced concrete tower 900 is tensioned, the upper ring prefabricated component 100 and the lower ring prefabricated component 110, under the vertical tightening force provided by the tower prestressing system, firmly clamp and secure the foundation prefabricated component 300 located between them. This scheme makes full use of the clamping and pre-tightening force provided by the prestressing system of the steel-concrete tower 900, realizing the coordinated and integrated force bearing of the steel-concrete tower 900 and the prefabricated assembled beam and slab foundation, effectively reducing structural redundancy and material waste.

[0108] Specifically, the force transmission path in this embodiment is as follows: After the prestressed components 600 of the reinforced concrete tower 900 complete the pre-tensioning, the prestressing tendons transmit the clamping pre-tightening force through the annular precast segments and the lower prestressing system of the reinforced concrete tower 900 to the upper annular precast component 100 and the lower annular precast component 110, applying a vertical contraction tightening force to the upper annular precast component 100 and the lower annular precast component 110. Under the action of the vertical contraction tightening force, the upper annular precast component 100 and the lower annular precast component 110 generate a relative tightening tendency, firmly clamping the foundation precast component 300 located between them, thereby effectively suppressing the vertical misalignment and relative slippage between the precast components under the wind turbine operating load.

[0109] Furthermore, each prestressed connection structure provided in this embodiment has a clear stress-bearing function and beneficial effect: the circumferential prestressed component 500 applies circumferential prestress to the precast foundation component 300 assembled into a ring along the circumferential direction, which can effectively resist the separation tendency of each precast foundation component 300 along the circumferential direction and prevent the assembly joint 400 from opening under alternating loads; the second anchor bolt component 210 is inserted horizontally between the lower ring precast component 110 and the precast foundation component 300, which can effectively resist the radial separation tendency between the precast foundation component 300 and the lower ring precast component 110, ensuring a reliable connection between the two under horizontal loads; the first anchor bolt component 200 is inserted vertically between the upper ring precast component 100 and the precast foundation component 300, which can effectively resist the vertical separation tendency between the upper ring precast component 100 and the precast foundation component 300, preventing the two from separating under vertical pull-out force. The three types of prestressed connection structures mentioned above work together with the tower prestressed components 600 to apply multi-directional pre-tightening constraints to the prefabricated assembled beam and slab foundation from three dimensions: circumferential, radial, and vertical. This ensures that the foundation as a whole remains tightly fitted and shares the load under the multi-condition load of the wind turbine, significantly improving the overall stiffness, connection reliability, and multi-condition adaptability of the foundation structure.

[0110] In one embodiment, the present invention also provides a design method for prefabricated assembled beam-slab foundations, which includes the following steps:

[0111] Step 1: Based on the initial structural parameters, the design loads acting on the tower and the prefabricated assembled beam and slab foundation are calculated by using a coupled solution method of aerodynamic load and structural dynamics.

[0112] Step 2: Based on the design load, perform structural design and performance verification on the tower structure and the prefabricated assembled beam-slab foundation respectively to obtain updated structural parameters and foundation stiffness.

[0113] Step 3: Based on the updated structural parameters and foundation stiffness, recalculate the design load and verify the overall frequency of the machine.

[0114] Step 4: Determine if the following convergence conditions are met simultaneously:

[0115] The inherent frequency of the entire machine is within the preset range;

[0116] The strength, fatigue, and prestress calculations of the tower structure meet the design criteria.

[0117] The overall stability, strength, fatigue, and connection node strength of the precast assembled beam-slab foundation meet the design criteria.

[0118] If all conditions are met, the final structural design scheme is output; if any condition is not met, return to step three and continue iterating until all convergence conditions are met.

[0119] Specifically, the design method for prefabricated assembled beam-slab foundations provided by this invention mainly includes three parts: load calculation, steel-concrete tower 900 structural design, and prefabricated assembled beam-slab foundation structural design.

[0120] 1) Load calculation: The main contents of load calculation include tower load calculation, foundation load calculation and whole machine frequency verification calculation.

[0121] The calculation method adopts a coupled solution approach of aerodynamic load and structural dynamics: aerodynamic load is calculated based on the classical engineering algorithm of BEM blade element momentum; structural dynamics adopts a combination of finite element modal condensation and flexible multibody time-domain coupled solution; and in accordance with the IEC wind power design code, all input conditions, load statistics and result verification are systematically calculated and statistically analyzed to obtain the design loads acting on the 900mm steel-concrete tower and the prefabricated assembled beam and slab foundation.

[0122] 2) Steel-concrete tower structure design: The main contents of the steel-concrete tower 900 structure design include: tower compressive strength verification, tensile strength verification, tower fatigue verification, and stress loss and strength verification of prestressed system components.

[0123] The design methodology employs a composite design approach that combines standardized engineering algorithms with refined finite element simulation.

[0124] Standardized engineering algorithm: Based on the current design specifications for wind power, concrete and steel structures, the overall strength, fatigue performance and prestressing system of the steel-concrete tower (900) are verified to determine the overall structural shape and prestressing configuration scheme of the tower.

[0125] Finite element refined simulation: Establish a numerical model including detailed structures such as prestressed tendons, steel-concrete transition nodes, and precast joints, carry out multi-condition simulation analysis, complete the special strength verification of local concrete, steel bars and connection nodes, and ensure the safety and rationality of the steel-concrete tower (900) structural design.

[0126] 3) Design of Precast Assembled Beam-Slab Foundation Structure: The design verification of precast assembled beam-slab foundations covers the overall structural stability, overall deformation, component mechanical strength, and durability fatigue performance, specifically including:

[0127] Overall stability verification: Verification of stability indicators such as overall foundation bearing capacity, overturning resistance, sliding resistance, and foundation bottom separation rate;

[0128] Overall deformation verification: verification of overall settlement and uneven deformation of the foundation;

[0129] Component strength verification: tensile and compressive strength verification of concrete for foundation precast component 300, including column 330, base plate 340 and rib beam 350; strength verification of upper ring precast component 100 and lower ring precast component 110; and reinforcement strength verification.

[0130] Fatigue performance verification: Fatigue performance verification of foundation concrete and steel reinforcement under alternating loads;

[0131] Strength verification of connection nodes: Strength verification of connection nodes such as the first anchor bolt assembly 200, the second anchor bolt assembly 210, the circumferential prestressing assembly 500, the tower prestressing assembly 600, and the pre-embedded connecting nail steel plate assembly 700.

[0132] The design methodology employs a composite design verification approach that combines standardized engineering algorithms with refined finite element simulation. The specific steps are as follows:

[0133] Based on the current design specifications for wind power foundations, ground foundations, reinforced concrete structures, etc., the overall stability and deformation performance of the foundation are checked and calculated using engineering algorithms to determine the overall structural shape of the foundation, including the outer diameter of the foundation, the height of the foundation, the thickness of the base plate (340), and the dimensions of the columns (330).

[0134] Based on the on-site transportation conditions and actual geological conditions, the suitability calculations of the number of segments, the size and weight of each component of the precast assembled beam and slab foundation were performed to determine the number of circumferential segments (corresponding to the 330-degree fan-shaped central angle of the column), the number of arc-shaped precast blocks of the upper ring precast component 100 and the lower ring precast component 110, and to form a preliminary design scheme.

[0135] Through refined three-dimensional finite element numerical simulation, a complete numerical model was established, including detailed structures such as the upper ring precast component 100, the lower ring precast component 110, the foundation precast component 300, the assembly joint 400, the first anchor bolt assembly 200, the second anchor bolt assembly 210, the circumferential prestressing assembly 500, the tower prestressing assembly 600, and the embedded connecting nail steel plate assembly 700. The overall stability, structural deformation, overall structural strength, structural fatigue strength, and connection node strength of the precast assembled beam-slab foundation were accurately verified under multiple working conditions to ensure that the structural design is safe and reliable and adaptable to the actual working conditions of the project.

[0136] The design method of this invention adopts a load-structure coupled iterative design process, and the specific calculation steps are as follows:

[0137] Step 1: Calculate the initial load based on the initial structural shape.

[0138] Step 2: Based on the initial load, conduct preliminary design of the 900mm steel-concrete tower and prefabricated assembled beam-slab foundation to obtain the preliminary structural shape and foundation stiffness for the second load calculation.

[0139] Step 3: Conduct the second version of load calculation and overall frequency verification to obtain the 900 load on the steel-concrete tower and the foundation load.

[0140] Step 4: Conduct the second version of the steel-concrete tower 900 and prefabricated assembled beam and slab foundation design to obtain the corresponding structural shape and foundation stiffness for subsequent load iteration calculations.

[0141] Step 5: Referring to Steps 3 and 4, carry out iterative calculations for load calculation, frequency verification, and design of the 900mm steel-concrete tower and prefabricated beam-slab foundation.

[0142] Step 6: Determine whether all convergence conditions in Step 4 are met simultaneously. If all conditions are met, end the iterative calculation and obtain the final load results, the 900mm steel-concrete tower structure scheme, and the prefabricated beam-slab foundation structure scheme. If any condition is not met, return to Step 3 and continue iterating until all convergence conditions are met.

[0143] Through the above load-structure coupling iterative design process, the steel-concrete tower 900 and the prefabricated beam-slab foundation are coordinated and unified in terms of structural shape, stiffness matching and bearing capacity, and finally form an overall structural scheme for wind turbine that meets the requirements of actual engineering conditions.

[0144] In one embodiment, reference is made to Figure 10 This embodiment provides an assembly method for a prefabricated precast beam-slab foundation, used to assemble the prefabricated precast beam-slab foundation described in any one of Embodiments 1 to 7 above. The assembly method includes the following steps:

[0145] S1. Pour the foundation pad layer 800mm.

[0146] Based on the design elevation and plan dimensions, a foundation pad layer of 800mm is poured at the bottom of the excavation pit. The foundation pad layer of 800mm can be made of plain concrete, and its top surface should be flat, with the elevation deviation controlled within the allowable range, to provide a flat support surface for the subsequent assembly of precast components.

[0147] S2. A sand layer 810 is laid on the top surface of the foundation pad 800 and at the preset installation position corresponding to the foundation precast component 300.

[0148] A sand layer 810 is laid on the top surface of the foundation pad 800 at the pre-set installation position of the base slab 340 of the precast foundation component 300. The sand layer 810 uses medium-coarse sand or graded gravel, with a thickness determined by the design. After laying, it is leveled and compacted. The sand layer 810 provides uniform support for the base slab 340 of the precast foundation component 300 and, through the compressibility of the sand layer, accommodates minor unevenness on the bottom surface of the base slab 340, ensuring uniform contact between the base slab 340 and the supporting surface. The base slab 340 of the precast foundation component 300 rests directly on the sand layer 810, eliminating the need for grouting between the base slab 340 and the foundation pad 800. This avoids the problem of grouting material having difficulty setting and hardening in low-temperature environments, allowing foundation construction to be unaffected by the strict constraints of low-temperature winter conditions.

[0149] S3. Hoist the lower ring prefabricated component 110 into place.

[0150] The precast lower ring component 110 is hoisted to the designed position above the foundation pad 800, and its planar position and elevation are adjusted to ensure accurate positioning.

[0151] S4. Filling material is applied to the assembly joint 400 between the lower ring precast component 110 and each foundation precast component 300, and to the assembly joint 400 between two adjacent foundation precast components 300. Then, each foundation precast component 300 is hoisted to the top of the lower ring precast component 110 in sequence along the circumferential direction.

[0152] Specifically, filling material is first applied to the assembly joints 400 between the lower ring precast component 110 and each foundation precast component 300, as well as the assembly joints 400 between two adjacent foundation precast components 300. Then, each foundation precast component 300 is sequentially hoisted to the top of the lower ring precast component 110 along the circumferential direction, so that the horizontal mating surface 311 of the stepped notch 310 mates with the upper surface of the lower ring precast component 110, and the vertical mating surface 312 of the stepped notch 310 mates with the outer circumferential surface of the lower ring precast component 110. Through the bidirectional self-positioning mating of the stepped notch 310, the foundation precast component 300 automatically completes vertical and radial positioning during hoisting and placement, without the need for additional positioning fixtures or measurement adjustments.

[0153] S5. Apply filling material to the assembly joint 400 between the upper ring precast component 100 and each foundation precast component 300, and then hoist the upper ring precast component 100 to the top of each foundation precast component 300.

[0154] Specifically, filling material is first applied to the assembly joints 400 between the upper ring precast component 100 and each foundation precast component 300. Then, the upper ring precast component 100 is hoisted onto the top of each foundation precast component 300, so that the lower surface of the upper ring precast component 100 mates with the upper surface of the foundation precast component 300. When the lower surface of the upper ring precast component 100 has a protrusion 101 and the upper surface of the foundation precast component 300 has a groove 320, the protrusion 101 is embedded in the groove 320 during hoisting, achieving circumferential positioning.

[0155] S6. Install the first anchor bolt assembly 200, the second anchor bolt assembly 210, and the circumferential prestressed assembly 500.

[0156] The first anchor bolt assembly 200 is inserted between the upper ring precast component 100 and the foundation precast component 300, and the second anchor bolt assembly 210 is inserted between the lower ring precast component 110 and the foundation precast component 300. The nuts are then tightened to reliably connect the precast components into a whole.

[0157] S7. Install the steel-concrete tower 900 onto the upper ring precast component 100, and install and tension the tower prestressing component 600 of the steel-concrete tower 900.

[0158] The bottom end of the reinforced concrete tower 900 is connected and fixed to the top surface of the upper ring precast component 100. Then, the tower prestressing component 600 of the reinforced concrete tower 900 is installed and tensioned. The reinforced concrete tower 900 and its prestressing system clamp and fasten the upper ring precast component 100 and the lower ring precast component 110. The upper ring precast component 100 and the lower ring precast component 110 then clamp and fasten the foundation precast component 300 located between them. Thus, the reinforced concrete tower 900 and the precast assembled beam and slab foundation form an integrated and stress-coordinated structure, completing the assembly of the wind turbine tower and foundation.

[0159] The assembly method in this embodiment transforms the traditional on-site concrete pouring operation of approximately 1000m³ for cast-in-place foundations into a factory prefabrication and on-site dry assembly operation. The construction process is clear and the operation is simple, significantly reducing the amount of on-site wet work and the need for transporting commercial concrete, thus significantly shortening the foundation construction cycle. The sand layer 810 eliminates the need for grouting the base slab 340, overcoming the limitations of winter construction. The self-positioning fit of the stepped notch 310 reduces the difficulty of on-site assembly and improves construction efficiency and assembly accuracy.

[0160] As an optional implementation of this application, this embodiment further defines the assembly method when the upper ring prefabricated component 100 and the lower ring prefabricated component 110 are formed by assembling and welding arc-shaped prefabricated blocks.

[0161] Both the upper ring precast component 100 and the lower ring precast component 110 are formed by sequentially splicing and enclosing several arc-shaped precast blocks evenly distributed along the ring direction to form a complete ring.

[0162] The assembly method before S3 also includes: splicing several arc-shaped prefabricated blocks in sequence along the circumferential direction, so that the end faces of the steel plates 710 of adjacent arc-shaped prefabricated blocks abut against each other at the end faces of the circumferential joint, and welding and fixing the abutting steel plates 710 to form the lower ring prefabricated component 110.

[0163] The assembly method after S5 also includes: splicing several arc-shaped prefabricated blocks in sequence along the circumferential direction, so that the end faces of the steel plates 710 of adjacent arc-shaped prefabricated blocks abut against each other at the end faces of the circumferential joint, and welding and fixing the abutting steel plates 710 to form the upper ring prefabricated component 100.

[0164] Specifically, during factory prefabrication of the arc-shaped precast blocks, the connecting nails 720 of the pre-embedded connecting nail steel plate assembly 700 are anchored within the concrete of the arc-shaped precast blocks, and the surface of the steel plate 710 is exposed at the circumferential joint end face of the arc-shaped precast blocks. During on-site assembly, the arc-shaped precast blocks are positioned sequentially along the circumferential direction, so that the end faces of the steel plates 710 of adjacent arc-shaped precast blocks abut against each other. Welding is then performed to weld and fix the adjacent steel plates 710, thus completing the assembly of the ring. Butt welding or bevel welding can be used, and the weld quality should meet the relevant standard requirements.

[0165] The assembly and welding of the lower ring precast component 110 is completed before S3, that is, the arc-shaped precast blocks are first assembled and welded into a complete ring on the ground or in the foundation pit, and then hoisted into place as a whole. The assembly and welding of the upper ring precast component 100 is completed after S5, that is, the arc-shaped precast blocks are placed one by one on top of the foundation precast component 300 and assembled and welded into a complete ring.

[0166] The method of prefabricating the arc-shaped precast blocks in sections and assembling and welding them on-site allows for controllable size and weight of individual components, facilitating standardized factory production and transportation, and solving the problem of difficult overall transportation of large-diameter ring components. The combination of steel plate 710 welding and connecting nails 720 anchoring ensures reliable connection of the circumferential joints, giving the assembled ring structure structural performance comparable to a monolithic cast ring. The lower ring precast component 110 is assembled first and then hoisted as a whole, while the upper ring precast component 100 is assembled and welded piece by piece on top of the foundation precast component 300. This reasonable construction arrangement balances construction convenience and structural reliability.

[0167] Furthermore, the assembly joints 400 between the precast components can be filled with grout, bedding grout, or epoxy resin. Since the upper ring precast component 100, lower ring precast component 110, and foundation precast component 300 are all manufactured and cured in the precast component factory, only component hoisting and assembly operations are required on-site, significantly reducing the amount of wet work. In particular, when bedding grout or epoxy resin is used as the filling material for the assembly joints 400, both grout and epoxy resin have excellent low-temperature construction performance, allowing for normal setting and hardening in low-temperature environments. This effectively adapts to the low-temperature construction environment in winter, thus solving the technical problem of traditional cast-in-place foundations being unable to be constructed in winter due to the difficulty of setting and hardening large volumes of concrete under low-temperature conditions, significantly extending the seasonal window for foundation construction.

[0168] In one embodiment, this embodiment provides a wind turbine generator, including a reinforced concrete tower 900 and the aforementioned prefabricated assembled beam-slab foundation, as well as a nacelle and rotor disposed at the top of the reinforced concrete tower 900. The bottom end of the reinforced concrete tower 900 is connected and fixed to the top surface of the upper ring prefabricated component 100.

[0169] Specifically, the bottom flange of the reinforced concrete tower 900 is fixed to the top surface of the upper ring precast component 100 by anchor bolts. The vertical force, horizontal force, and overturning moment generated during wind turbine operation are transmitted to the foundation through the reinforced concrete tower 900 and its prestressing system. Specifically, the reinforced concrete tower 900 transmits the load to the upper ring precast component 100, and the prestressing system of the reinforced concrete tower 900 transmits the load to the lower ring precast component 110. The precast upper ring 900 and the lower ring precast component 110 together clamp and secure the upper ring precast component 100. The upper ring precast component 100 and the lower ring precast component 110 further clamp and reinforce the foundation precast component 300 located between them. This creates an integrated load-bearing structure comprising the reinforced concrete tower 900, the prestressed system, the upper ring precast component 100, the foundation precast component 300, and the lower ring precast component 110. The load is ultimately diffused and transferred to the ground through the foundation pad 800. This design fully utilizes the structural strength of the reinforced concrete tower 900 itself to assist the foundation in bearing the load, reducing the independent load-bearing requirements of the foundation itself.

[0170] The wind turbine in this embodiment adopts the above-mentioned prefabricated assembled beam and slab foundation. The foundation construction quality is controllable, the construction efficiency is high, and construction can be carried out in winter. Moreover, the overall rigidity and bearing capacity of the foundation structure meet the load transfer requirements of the 900mm steel-concrete tower, providing a reliable foundation solution for steel-concrete tower wind turbines and filling the technical gap in the field of prefabricated assembled foundations adapted to steel-concrete towers at home and abroad.

[0171] In summary, the prefabricated components of the prefabricated beam-slab foundation described in this invention can be rationally designed based on the transportation conditions and load conditions of different regions. By adjusting the number of circumferential segments, the number of arc-shaped prefabricated blocks, and the component size, a prefabricated component size scheme that is both economical and transportable can be obtained, effectively solving the engineering problem of transportation restrictions on large-sized foundation components.

[0172] This invention employs an integrated design method for the steel-concrete tower and foundation, fully utilizing the structural strength of the steel-concrete tower itself and the clamping effect of the prestressed system to form an integral load-bearing system with the prefabricated beam-slab foundation, effectively improving the overall connection reliability and stress stability. Simultaneously, by adjusting the stiffness of the prefabricated foundation structure, the overall frequency distribution of the unit can be optimized, avoiding overall resonance and ensuring the safe operation of the unit.

[0173] The precast precast beam-slab foundation of this invention employs three types of prestressed connection structures for coordinated fastening: a first anchor bolt assembly 200 vertically connects the upper ring precast component 100 to the foundation precast component 300; a second anchor bolt assembly 210 horizontally connects the lower ring precast component 110 to the foundation precast component 300; and a circumferential prestressed assembly 500 tightly clamps each foundation precast component 300 circumferentially. Through the synergistic effect of these three types of prestressed connection systems, the overall connection stiffness and adaptability to various working conditions of the foundation are significantly improved.

[0174] The upper ring prefabricated component 100 and the lower ring prefabricated component 110 of the present invention adopt a modular structure that is detachable and adjustable in size. By adjusting the number and size of the arc-shaped prefabricated blocks, they can be adapted to different wind load conditions and geological conditions, realize the universalization and standardization of mold production, effectively reduce production costs, and improve the component reuse rate.

[0175] All components of the prefabricated beam-slab foundation described in this invention are prefabricated in the factory, eliminating the need for on-site concrete pouring. Combined with sand leveling of the base slab, grout filling of 400 joints, and epoxy resin sealing of the joints, foundation construction can be completed in low-temperature environments. This effectively solves the industry problem of traditional cast-in-place foundations being unable to be constructed in winter, significantly extending the seasonal window for foundation construction.

[0176] The embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the present invention is not limited to the above embodiments, and various changes can be made within the scope of knowledge possessed by those skilled in the art without departing from the spirit of the present invention. Furthermore, the embodiments of the present invention and the features thereof can be combined with each other unless otherwise specified.

Claims

1. A precast assembled beam-slab foundation, characterized in that: It includes an upper ring precast component (100), a lower ring precast component (110), a first anchor bolt assembly (200), a second anchor bolt assembly (210), and multiple foundation precast components (300). The lower ring prefabricated component (110) is disposed on the foundation pad layer (800), and multiple foundation prefabricated components (300) are sequentially assembled on the top of the lower ring prefabricated component (110) along the circumferential direction. The upper ring prefabricated component (100) is disposed on the top of the multiple foundation prefabricated components (300). The lower end of the basic precast component (300) near the lower ring precast component (110) is provided with a stepped notch (310). The horizontal mating surface (311) of the stepped notch (310) mates with the upper surface of the lower ring precast component (110), and the vertical mating surface (312) of the stepped notch (310) mates with the outer peripheral surface of the lower ring precast component (110). The lower surface of the upper ring prefabricated component (100) mates with the upper surface of the foundation prefabricated component (300); The assembly joints (400) formed between two adjacent prefabricated foundation components (300), between the lower ring prefabricated component (110) and the prefabricated foundation component (300), and between the upper ring prefabricated component (100) and the prefabricated foundation component (300) are filled with filling material. The first anchor bolt assembly (200) is inserted between the upper ring precast component (100) and the foundation precast component (300); the second anchor bolt assembly (210) is inserted between the lower ring precast component (110) and the foundation precast component (300).

2. The precast assembled beam-slab foundation according to claim 1, characterized in that: It also includes a circumferential prestressed component (500) which is arranged circumferentially around a plurality of the foundation precast components (300).

3. The precast assembled beam-slab foundation according to claim 1, characterized in that: It also includes a tower prestressing assembly (600), wherein the lower ring prefabricated component (110), the foundation prefabricated component (300) and the upper ring prefabricated component (100) are respectively provided with mounting holes for the tower prestressing assembly (600) to pass through; The tower prestressed assembly (600) is sequentially fitted with the upper ring precast component (100), the foundation precast component (300), and the lower ring precast component (110) from top to bottom. After tensioning, a vertical shrinkage tightening force is applied to the upper ring precast component (100) and the lower ring precast component (110), causing the upper ring precast component (100) and the lower ring precast component (110) to have a relative tightening tendency, so as to clamp and fasten the foundation precast component (300) located between the upper ring precast component (100) and the lower ring precast component (110), and constrain the vertical relative displacement between each precast component.

4. The precast assembled beam-slab foundation according to claim 1, characterized in that: The lower surface of the upper ring prefabricated component (100) is provided with a protrusion (101) along the circumferential direction, and the upper surface of the foundation prefabricated component (300) is provided with a groove (320) that matches the protrusion (101).

5. The precast assembled beam-slab foundation according to claim 1, characterized in that: The precast foundation components (300) include columns (330), base plates (340), and ribs (350). The column (330) is arranged vertically, and its horizontal projection is fan-shaped. When multiple foundation prefabricated components (300) are assembled into a ring along the circumferential direction, the fan-shaped horizontal projections of each column (330) are sequentially assembled to form a complete ring. The central angle of the fan shape corresponds to the number of circumferential segments. The top surface of the column (330) matches the lower surface of the upper ring prefabricated component (100). The bottom end of the column (330) is provided with a stepped notch (310) for positioning and matching with the lower ring prefabricated component (110). The base plate (340) is horizontally disposed on the outer side of the bottom end of the column (330), and the bottom surface of the base plate (340) is fitted with the foundation pad (800); The rib (350) is a right-angled triangular plate, with one right-angled side connected to the outer side of the pedestal (330) and the other right-angled side connected to the upper surface of the base plate (340). The rib (350), the pedestal (330) and the base plate (340) are integrally cast and formed to enclose a triangular stiffening structure.

6. The precast assembled beam-slab foundation according to claim 1, characterized in that: The upper ring prefabricated component (100) and the lower ring prefabricated component (110) are both formed by splicing and enclosing several arc-shaped prefabricated blocks evenly distributed along the ring direction in sequence. The adjacent arc-shaped prefabricated blocks are welded together by pre-embedded connecting nail steel plate assembly (700). The pre-embedded connecting nail steel plate assembly (700) includes a steel plate (710) and a plurality of connecting nails (720) disposed on one side of the steel plate (710). The connecting nails (720) are anchored in the concrete corresponding to the arc-shaped precast block. The plate surface of the steel plate (710) is exposed on the circumferential joint end face of the arc-shaped precast block. The steel plates (710) of two adjacent arc-shaped precast blocks are welded and fixed at the circumferential joint end face.

7. The precast assembled beam-slab foundation according to claim 1, characterized in that: The first anchor bolt assembly (200) passes through the upper ring prefabricated component (100) and the foundation prefabricated component (300) in a vertical direction to fix the upper ring prefabricated component (100) and the foundation prefabricated component (300) together. The second anchor bolt assembly (210) passes through the lower ring precast component (110) and the foundation precast component (300) in a horizontal direction to fix the lower ring precast component (110) and the foundation precast component (300) together.

8. A method for assembling a precast assembled beam-slab foundation, characterized in that, include: S1. Pour the foundation pad (800). S2. A sand layer (810) is laid on the top surface of the foundation pad (800) and at the preset installation position corresponding to the foundation prefabricated component (300). S3. Hoist the lower ring prefabricated component (110) into place; S4. Filling material is applied to the assembly joint (400) between the lower ring prefabricated component (110) and each of the foundation prefabricated components (300), and to the assembly joint (400) between two adjacent foundation prefabricated components (300). Then, each of the foundation prefabricated components (300) is hoisted to the top of the lower ring prefabricated component (110) in sequence along the circumferential direction, so that the horizontal mating surface (311) of the stepped notch (310) mates with the upper surface of the lower ring prefabricated component (110), and the vertical mating surface (312) of the stepped notch (310) mates with the outer peripheral surface of the lower ring prefabricated component (110). S5. Apply filling material to the assembly joint (400) between the upper ring prefabricated component (100) and each of the foundation prefabricated components (300), and then hoist the upper ring prefabricated component (100) to the top of each of the foundation prefabricated components (300), so that the lower surface of the upper ring prefabricated component (100) matches the upper surface of the foundation prefabricated component (300); S6. Install the first anchor bolt assembly (200), the second anchor bolt assembly (210), and the circumferential prestressed assembly (500), such that the first anchor bolt assembly (200) passes between the upper ring precast component (100) and the foundation precast component (300), and the second anchor bolt assembly (210) passes between the lower ring precast component (110) and the foundation precast component (300); S7. Install the steel-concrete tower (900) on the upper ring prefabricated component (100) and install and tension the tower prestressing component (600) of the steel-concrete tower (900).

9. The assembly method for prefabricated assembled beam-slab foundations according to claim 8, characterized in that, The upper ring prefabricated component (100) and the lower ring prefabricated component (110) are both formed by splicing and enclosing several arc-shaped prefabricated blocks evenly distributed along the ring direction in sequence to form a complete ring. The assembly method further includes, before S3: sequentially splicing several of the arc-shaped prefabricated blocks along the circumferential direction, such that the end faces of the steel plates (710) of adjacent arc-shaped prefabricated blocks abut against each other at the circumferential joint end faces, and welding and fixing the abutting steel plates (710) to form the lower ring prefabricated component (110). The assembly method further includes, after step S5, the following: sequentially splicing several of the arc-shaped prefabricated blocks along the circumferential direction, such that the end faces of the steel plates (710) of adjacent arc-shaped prefabricated blocks abut against each other at the circumferential joint end faces, and welding and fixing the abutting steel plates (710) to form the upper ring prefabricated component (100).

10. A design method for precast assembled beam-slab foundations, characterized in that, Includes the following steps: Step 1: Based on the initial structural parameters, the design loads acting on the tower and the prefabricated assembled beam and slab foundation are calculated by using a coupled solution method of aerodynamic load and structural dynamics. Step 2: Based on the design load, perform structural design and performance verification on the tower structure and the prefabricated assembled beam-slab foundation respectively to obtain updated structural parameters and foundation stiffness. Step 3: Based on the updated structural parameters and foundation stiffness, recalculate the design load and verify the overall frequency of the machine. Step 4: Determine if the following convergence conditions are met simultaneously: The inherent frequency of the entire machine is within the preset range; The strength, fatigue, and prestress calculations of the tower structure meet the design criteria. The overall stability, strength, fatigue, and connection node strength of the precast assembled beam-slab foundation meet the design criteria. If all conditions are met, the final structural design scheme will be output. If any condition is not met, return to step three and continue iterating until all convergence conditions are met.

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