Rib plate assembly type prestressed concrete fan foundation and mounting method thereof

Abstract

According to the ribbed plate assembly type prestressed concrete fan foundation and the installation method thereof, all the parts are prefabricated in a factory, then prefabricated parts are assembled on site, and the problem that the construction period of a cast-in-place foundation is long can be solved. Comprising a foundation outer ring, a foundation middle ring, a foundation pedestal and a foundation inner ring which are sequentially in butt joint from outside to inside in the radial direction. The foundation outer ring comprises a plurality of arc-shaped outer ring assembling bodies which are sequentially in butt joint in the circumferential direction. The foundation middle ring comprises a plurality of arc-shaped middle ring assembling bodies which are sequentially in butt joint in the circumferential direction. The basic pedestal comprises a plurality of arc-shaped pedestal assembling bodies which are sequentially in butt joint in the circumferential direction; the foundation inner ring comprises a plurality of arc-shaped inner ring assembling bodies which are sequentially in butt joint in the circumferential direction. The outer ring assembly body, the middle ring assembly body, the pedestal assembly body and the inner ring assembly body are all prefabricated parts; radial supporting rib plates are distributed on the outer circumferential surface and the inner circumferential surface of the foundation pedestal at intervals in the circumferential direction; prestressed steel strands are arranged in the supporting rib plates for tensioning.

Description

Technical Field

[0001] The present invention relates to a fan foundation, in particular to a concrete fan foundation, belonging to the technical fields of structural engineering and new energy wind power. Background Art

[0002] In recent years, with the continuous and rapid development of wind power, wind power has been developing towards large-capacity units (18MW+), high hubs (180m+), and long blades (140m+), and the size of the wind power foundation needs to be further increased.

[0003] Common on-site cast fan foundation forms include spread foundations, beam-slab foundations, rock prestressed anchor foundations, and pile foundations, which have been widely used in actual projects. Each of the above foundations has some disadvantages:

[0004] (1) The main disadvantages of spread foundations and beam-slab foundations are: dense steel bars, large steel bar consumption; on-site formwork erection and casting are required, and the construction period is long; when the tower barrel is in the form of a concrete tower, large-sized corbels need to be set.

[0005] (2) The main disadvantage of the rock prestressed anchor foundation is that it must be a rock foundation and on-site casting is required.

[0006] (3) The main disadvantages of pile foundations are: dense steel bars, large steel bar consumption; on-site formwork erection and casting are required, and the construction period is long; when the tower barrel is in the form of a concrete tower, large-sized corbels need to be set. Summary of the Invention

[0007] In view of this, the present invention provides a ribbed plate prefabricated prestressed concrete fan foundation, which can solve the defects existing in the existing on-site cast fan foundation.

[0008] The technical solution of the present invention is: a ribbed plate prefabricated prestressed concrete fan foundation, including: a foundation outer ring, a foundation middle ring, a foundation pedestal, and a foundation inner ring that are sequentially butted from the outside to the inside along the radial direction;

[0009] The foundation outer ring includes a plurality of arc-shaped outer ring assemblies that are sequentially butted along the circumferential direction;

[0010] The foundation middle ring includes a plurality of arc-shaped middle ring assemblies that are sequentially butted along the circumferential direction;

[0011] The foundation pedestal includes a plurality of arc-shaped pedestal assemblies that are sequentially butted along the circumferential direction;

[0012] The foundation inner ring includes a plurality of arc-shaped inner ring assemblies that are sequentially butted along the circumferential direction;

[0013] The outer ring assembly, the middle ring assembly, the pedestal assembly, and the inner ring assembly are all prefabricated parts;

[0014] Radial support rib plates are circumferentially and spacedly distributed on both the outer circumferential surface and the inner circumferential surface of the base pedestal; prestressed steel strands are arranged inside the support rib plates for radial tensioning.

[0015] As a preferred embodiment of the present invention: the inner ring of the base has an inner strengthening ring, the center of the inner strengthening ring is the central area of the base, and the central area of the base is cast in place with concrete.

[0016] As a preferred embodiment of the present invention: the outer ring assembly includes: a precast outer ring bottom plate, a precast base outer ring beam and precast outer ring rib plates;

[0017] The precast outer ring rib plates are vertically arranged at the middle position in the arc length direction of the precast outer ring bottom plate, and the precast outer ring rib plates extend radially along the precast outer ring bottom plate and are of the same width as the precast outer ring bottom plate;

[0018] The precast base outer ring beam is vertically arranged at the outer edge of the precast outer ring bottom plate and has the same arc length as the precast outer ring bottom plate; the precast base outer ring beam protrudes from the precast outer ring bottom plate, and the outer ends of the precast outer ring rib plates are butted against the precast base outer ring beam; the precast base outer ring beams of all the outer ring assemblies are butted circumferentially to form an integral outer ring beam.

[0019] As a preferred embodiment of the present invention: the middle ring assembly includes: a precast middle ring bottom plate, precast middle ring rib plate A and precast middle ring rib plate B;

[0020] The precast middle ring rib plate B is vertically arranged at the middle position in the arc length direction of the precast middle ring bottom plate, and the precast middle ring rib plate B extends radially along the precast middle ring bottom plate, and the radially outer end is butted against the inner end of the precast outer ring rib plate;

[0021] The precast middle ring rib plate A is an arc concentric with the precast middle ring bottom plate and is arranged at the middle position in the width direction of the precast middle ring bottom plate; after the precast middle ring rib plate A of each middle ring assembly is butted circumferentially, the precast middle ring rib plate A is butted circumferentially to form a ring.

[0022] As a preferred embodiment of the present invention: the pedestal assembly includes: a precast pedestal bottom plate, an inner side wall unit and an upper beam unit;

[0023] The inner side wall unit is vertically arranged on the precast pedestal bottom plate, and the inner side wall unit is an arc-shaped structure. The inner side wall units on all the pedestal assemblies are butted circumferentially in sequence to form an annular inner side wall;

[0024] The upper beam unit is an arc-shaped structure and is coaxially butted on the upper end surface of the inner side wall unit. The upper beam units on all the pedestal assemblies are butted circumferentially in sequence to form an upper annular beam; a number of prestressed ducts B are circumferentially and spacedly distributed on the end surface of each upper beam unit.

[0025] After the precast outer ring rib plates and the precast middle ring rib plates B are butt-jointed one by one, they are connected to the rib plate connectors on the outer circumferential surfaces of the internal side wall units and the upper beam units to form the external support rib plates.

[0026] As a preferred embodiment of the present invention: the inner ring assembly includes: a precast inner ring bottom plate, precast inner ring rib plates A, and precast inner ring rib plates B;

[0027] The precast inner ring rib plates B are vertically arranged at the middle position in the arc length direction of the precast inner ring bottom plate. The precast inner ring rib plates B extend radially along the precast inner ring bottom plate and are connected to the rib plate connectors on the inner circumferential surfaces of the internal side wall units and the upper beam units to form the internal support rib plates;

[0028] The precast inner ring rib plates A are vertically arranged along the inner edge of the precast inner ring bottom plate and have the same arc length as the precast inner ring bottom plate; the inner ends of the precast inner ring rib plates B are butt-jointed with the precast inner ring rib plates A; after the precast inner ring rib plates A are butt-jointed circumferentially, an internal strengthening ring is formed.

[0029] As a preferred embodiment of the present invention: there are two prestressed ducts A, one above the other, provided at the positions corresponding to the precast outer ring rib plates on the circumferential surface of the precast foundation outer ring beam;

[0030] Among them, the upper prestressed duct A penetrates through the support rib plate along the hypotenuse direction of the support rib plates at the corresponding positions on the outer circumferential surface and the inner circumferential surface of the foundation pedestal; the lower prestressed duct A penetrates through the support rib plates at the corresponding positions on the outer circumferential surface and the inner circumferential surface of the foundation pedestal radially;

[0031] The prestressed duct A is used for installing prestressed steel strands and tensioning; one end of the prestressed steel strand is located outside the wind turbine foundation, and the other end passes through the prestressed duct A and enters the foundation central area.

[0032] As a preferred embodiment of the present invention: a door opening is provided on the internal side wall unit of one of the pedestal assemblies;

[0033] A stairway is also provided at the position corresponding to the door opening, and stairway side walls are provided on both sides of the stairway.

[0034] In addition, the present invention provides an installation method for the above-mentioned rib plate assembled prestressed concrete wind turbine foundation,

[0035] S1: First, the processing of each precast component is completed in the factory, and then each precast component is transported to the site;

[0036] S2: Assemble the main body of the wind turbine foundation on the site:

[0037] During assembly, an assembly sequence from the inside to the outside is adopted:

[0038] First, assemble the basic internal ring, that is, dock each inner ring assembly circumferentially, and connect adjacent inner ring assemblies through cast-in-place wet joints;

[0039] Then, assemble the foundation pedestal outside the basic internal ring, that is, dock each pedestal assembly circumferentially, and connect adjacent pedestal assemblies through cast-in-place wet joints; at the same time, connect the pedestal assembly and the inner ring assembly radially through cast-in-place wet joints;

[0040] After that, assemble the middle part of the foundation outside the foundation pedestal, that is, dock each middle ring assembly circumferentially, and connect adjacent middle ring assemblies through cast-in-place wet joints; at the same time, connect the middle ring assembly and the pedestal assembly radially through cast-in-place wet joints;

[0041] Finally, assemble the outer part of the foundation outside the middle part of the foundation, that is, dock each outer ring assembly circumferentially, and connect adjacent outer ring assemblies through cast-in-place wet joints; at the same time, connect the outer ring assembly and the middle ring assembly radially through cast-in-place wet joints;

[0042] S3: Tension the prestressed steel strands:

[0043] Install and tension the prestressed steel strands in the prestressed duct A; one end of the prestressed steel strand is located outside the main body of the wind turbine foundation, and the other end passes through the prestressed duct A and enters the central area of the foundation; after tensioning, seal the anchor, and grout in the prestressed duct A.

[0044] S4: Pour concrete on-site in the central area of the foundation.

[0045] As a preferred embodiment of the present invention: the prestressed steel strands are tensioned unidirectionally or symmetrically.

[0046] Beneficial effects:

[0047] (1) For the ribbed precast prestressed concrete wind turbine foundation of the present invention, each component is prefabricated in the factory to form precast components, and then the precast components are assembled on-site, which can solve the problems of "requiring on-site formwork erection and casting, and long construction period" of the cast-in-place foundation.

[0048] (2) For the ribbed precast prestressed concrete wind turbine foundation of the present invention, prestressed steel strands are arranged radially, that is, prestressed steel strands are arranged up and down in the triangular outer rib and the triangular inner rib, with high strength, which can effectively improve the structural cracking, thereby reducing the amount of ordinary steel bars and solving the problems of "dense steel bars and large amount of steel bars" in the traditional scheme;

[0049] Moreover, one end of the prestressed steel strand is located inside, the concrete in the central area of the foundation is poured later, and the other end is located outside the foundation. The prestressed steel strand is tensioned at a single end, with an operating space and convenient construction.

[0050] (3) In the ribbed slab precast prestressed concrete wind turbine foundation of the present invention, the upper ring beam is adopted to replace the corbel of the concrete tower foundation, and a number of ribbed slabs are evenly distributed along the circumferential direction on both the outer circumferential surface and the inner circumferential surface of the inner side wall. The ribbed slabs are extended into the upper ring beam, that is, the force-bearing structure "corbel" of the cast-in-place structure is changed into a ring beam with multiple supports, reducing the structural size and the amount of steel bars used, and solving the problem of "when the tower barrel is in the form of a concrete tower, a corbel with a large size needs to be set".

[0051] (4) The ribbed slab precast prestressed concrete wind turbine foundation of the present invention adopts a division method combining radial and circumferential directions. First, the foundation is divided into an outer foundation ring, a middle foundation ring, a foundation pedestal, and an inner foundation ring. The central area is cast in place with concrete; the outer foundation ring, the middle foundation ring, the foundation pedestal, and the inner foundation ring are further divided into several assemblies assembled from precast components according to their respective sizes, facilitating the transportation of precast components.

[0052] (5) The ribbed slab precast prestressed concrete wind turbine foundation of the present invention is provided with a door opening on the inner side wall unit, so the door opening at the bottom of the wind turbine tower barrel can be cancelled, solving the problem of stress concentration at the door opening at the bottom of the wind turbine tower barrel.

[0053] (6) The ribbed slab precast prestressed concrete wind turbine foundation of the present invention is provided with an inner strengthening ring at the center, and the central area of the foundation uses plain concrete, which can avoid the problem of dense steel bars in the central area of the foundation. Description of the Drawings

[0054] Figure 1 is a three-dimensional structural schematic diagram of the ribbed slab precast prestressed concrete wind turbine foundation of the present invention;

[0055] Figure 2 is a three-dimensional line drawing of the ribbed slab precast prestressed concrete wind turbine foundation of the present invention;

[0056] Figure 3 is a structural schematic diagram after removing the upper ring beam and the inner side wall (showing the route of the prestressed steel strands);

[0057] Figure 4 is a structural schematic diagram of the upper ring beam and the inner side wall in the present invention;

[0058] Figure 5 is a structural schematic diagram of the upper ring beam in the present invention;

[0059] Figure 6 is a three-dimensional drawing of the door opening in the present invention;

[0060] Figure 7 is a schematic diagram of the cast-in-place wet joint in the present invention.

[0061] Wherein: 1 - Outer ring assembly, 101 - Prefabricated outer ring bottom plate, 102 - Prefabricated foundation outer ring beam, 103 - Prefabricated outer ring rib plate, 104 - Prestressed duct A;

[0062] 2 - Middle ring assembly, 201 - Prefabricated middle ring bottom plate, 202 - Prefabricated middle ring rib plate A, 203 - Prefabricated middle ring rib plate B;

[0063] 3 - Pedestal assembly, 301 - Prefabricated pedestal bottom plate, 302 - Inner side wall unit, 303 - Upper beam unit, 304 - Prestressed duct B, 305 - Door opening;

[0064] 4 - Inner ring assembly, 401 - Prefabricated inner ring bottom plate, 402 - Prefabricated inner ring rib plate A, 403 - Prefabricated inner ring rib plate B;

[0065] 5 - Canopy; 6 - Stairway side wall; 7 - Stairway; 8 - Cast-in-place wet joint; 9 - Prestressed steel strand A; 10 - Prestressed steel strand B. Detailed implementation mode

[0066] The present invention will be further described in detail below with reference to the drawings and embodiments.

[0067] Embodiment 1:

[0068] This embodiment provides a ribbed precast prestressed concrete fan foundation, which is precast in the factory, constructed in a fully precast manner, with fast on-site assembly, and adopts a prestressed concrete structure. Compared with a common cast-in-place reinforced concrete foundation, it can save the consumption of concrete and steel.

[0069] Each component in this concrete fan foundation is precast in the factory to form precast components, and then the precast components are assembled on-site. Moreover, a division method combining radial and circumferential directions is adopted during division, which is convenient for the transportation of precast components.

[0070] As Figures 1 - 3 shown, this concrete fan foundation includes: an outer foundation ring, a middle foundation ring, a foundation pedestal, and an inner foundation ring.

[0071] Among them, the outer foundation ring includes a plurality of arc-shaped outer ring assemblies 1 that are sequentially butted circumferentially. The outer ring assembly 1 is a precast component, and adjacent outer ring assemblies 1 are connected by a cast-in-place wet joint 8 to form a ring structure; the structure at the connection is as Figure 7 shown.

[0072] Each outer ring assembly 1 includes: a precast outer ring bottom plate 101, a precast basic outer ring beam 102, and a precast outer ring rib plate 103. Among them, the precast outer ring rib plate 103 is vertically arranged at the middle position in the arc length direction (i.e., circumferential direction) of the precast outer ring bottom plate 101, and the precast outer ring rib plate 103 extends radially along the precast outer ring bottom plate 101 and has the same width as the precast outer ring bottom plate 101 (the width refers to the radial dimension of the precast outer ring bottom plate 101); the precast basic outer ring beam 102 is vertically arranged at the outer edge of the precast outer ring bottom plate 101 (i.e., the outer side in the radial direction) and has the same arc length as the precast outer ring bottom plate 101; the precast basic outer ring beam 102 protrudes from the precast outer ring bottom plate 101, and the outer end of the precast outer ring rib plate 103 is butted against the precast basic outer ring beam 102. The precast basic outer ring beams 102 of all the outer ring assemblies 1 are butted circumferentially to form an integral outer ring beam.

[0073] The middle ring of the foundation is coaxially arranged inside the outer ring of the foundation, and its outer circumferential surface is butted against the inner circumferential surface of the outer ring of the foundation. The middle ring of the foundation includes a plurality of arc-shaped middle ring assemblies 2 that are butted in sequence circumferentially; the middle ring assemblies 2 are precast components, and adjacent middle ring assemblies 2 are connected by a cast-in-place wet joint 8 to form an annular structure.

[0074] As an example, the number of the middle ring assemblies 2 is the same as that of the outer ring assemblies 1 and they correspond one by one; each middle ring assembly 2 is butted radially inside the corresponding outer ring assembly 1.

[0075] Each middle ring assembly 2 includes a precast middle ring bottom plate 201, a precast middle ring rib plate A 202, and a precast middle ring rib plate B 203; among them, the precast middle ring rib plate B 203 is vertically arranged at the middle position in the arc length direction (i.e., circumferential direction) of the precast middle ring bottom plate 201, the precast middle ring rib plate B 203 extends radially along the precast middle ring bottom plate 201 and has the same width as the precast middle ring bottom plate 201 (the width refers to the radial dimension of the precast middle ring bottom plate 201); the outer end of the precast middle ring rib plate B 203 in the radial direction is butted against the inner end of the precast outer ring rib plate 103; the precast middle ring rib plate A 202 is an arc concentric with the precast middle ring bottom plate 201 and is arranged at the middle position in the width direction of the precast middle ring bottom plate 201; precast middle ring rib plates A 202 are arranged on both circumferential sides of the precast middle ring rib plate B 203 (it can also be understood that the precast middle ring rib plate A 202 is separated into left and right parts by the precast middle ring rib plate B 203). After the middle ring assemblies 2 are butted circumferentially, the precast middle ring rib plates A 202 are also butted circumferentially to form a ring.

[0076] The foundation pedestal is coaxially arranged inside the middle ring of the foundation, and its outer circumferential surface is butted against the inner circumferential surface of the middle ring of the foundation. The foundation pedestal includes a plurality of arc-shaped pedestal assemblies 3 that are butted in sequence circumferentially, and the pedestal assemblies 3 are precast components, and adjacent pedestal assemblies 3 are connected by a cast-in-place wet joint 8 to form an annular structure.

[0077] As Figures 4 - 6As shown in the figure, each pedestal assembly 3 includes: a precast pedestal bottom plate 301, an internal side wall unit 302, and an upper beam unit 303; the internal side wall unit 302 is vertically arranged on the precast pedestal bottom plate 301, the internal side wall unit 302 is an arc-shaped structure, and the internal side wall units 302 on all pedestal assemblies 3 are butt-jointed in sequence along the circumferential direction to form an annular internal side wall. A door opening 305 is provided on the internal side wall unit 302 of one of the pedestal assemblies 3. The upper beam unit 303 is an arc-shaped structure and is coaxially butt-jointed to the upper end face of the internal side wall unit 302, and the upper beam units 303 on all pedestal assemblies 3 are butt-jointed in sequence along the circumferential direction to form an upper annular beam.

[0078] On the end face of each upper beam unit 303, a number of prestressed ducts B304 are evenly spaced along the circumferential direction; the prestressed ducts B304 are the prestressed ducts reserved for the tower barrel.

[0079] The precast outer ring rib plates 103 are connected to the precast middle ring rib plates B203 one by one and then connected to the rib plate connectors on the outer circumferential surfaces of the internal side wall unit 302 and the upper beam unit 303 to form a complete triangular outer rib plate; thus, a number of triangular outer rib plates are evenly spaced along the circumferential direction on the outer circumferential surface of the whole formed by the internal side wall and the upper annular beam.

[0080] The foundation internal ring is coaxially arranged inside the foundation pedestal, and its outer circumferential surface is butt-jointed with the inner circumferential surface of the foundation pedestal. The foundation internal ring includes a number of arc-shaped inner ring assemblies 4 butt-jointed in sequence along the circumferential direction. The inner ring assemblies 4 are precast components, and adjacent inner ring assemblies 4 are connected by cast-in-place wet joints 8 to form an annular structure.

[0081] Each inner ring assembly 4 includes: a precast inner ring bottom plate 401, a precast inner ring rib plate A402, and a precast inner ring rib plate B403; among them, the precast inner ring rib plate B403 is vertically arranged at the middle position in the arc length direction (i.e., the circumferential direction) of the precast inner ring bottom plate 401, and the precast inner ring rib plate B403 extends radially along the precast inner ring bottom plate 401 and has the same width as the precast inner ring bottom plate 401 (the width refers to the radial dimension of the precast inner ring bottom plate 401).

[0082] The precast inner ring rib plate B403 is connected to the rib plate connectors on the inner circumferential surfaces of the internal side wall unit 302 and the upper beam unit 303 to form a complete triangular inner rib plate; thus, a number of triangular inner rib plates are evenly spaced along the circumferential direction on the inner circumferential surface of the whole formed by the internal side wall and the upper annular beam; the triangular inner rib plates and the triangular outer rib plates are in one-to-one correspondence in position.

[0083] The prefabricated inner ring rib plate A402 is vertically arranged along the inner edge of the prefabricated inner ring bottom plate 401 (i.e., the inner side in the radial direction), and has the same arc length as the prefabricated inner ring bottom plate 401; the prefabricated inner ring rib plate A402 protrudes from the prefabricated inner ring bottom plate 401, and the inner end of the prefabricated inner ring rib plate B403 is butted against the prefabricated inner ring rib plate A402. After the prefabricated inner ring rib plates A402 are butted along the circumferential direction, an internal strengthening ring is formed. The center of the internal strengthening ring is the basic center area.

[0084] At the positions corresponding to the prefabricated outer ring rib plates 103 on the circumferential surface of the prefabricated basic outer ring beam 102, there are two upper and lower prestressed ducts A104, and the prestressed ducts A104 penetrate through the triangular outer rib plates and triangular inner rib plates; after the fan foundation is assembled, prestressed steel strands are installed in the prestressed ducts A104 and tensioned. One end of the prestressed steel strand is located outside the fan foundation, and the other end passes through the prestressed duct A104 and enters the basic center area; the prestressed steel strand can be tensioned unidirectionally (such as the outside) or bidirectionally (the outside and the inside), and after tensioning, the anchor is sealed, and the prestressed duct A104 is grouted.

[0085] Figure 3 The tensioning route of the prestressed steel strand is shown (the prestressed steel strand is located inside the triangular outer rib plate and triangular inner rib plate, and is only used to show the tensioning route of the prestressed steel strand in this figure). Let the prestressed steel strand in the upper prestressed duct A104 be the prestressed steel strand A9, and the prestressed steel strand in the lower prestressed duct A104 be the prestressed steel strand B10. Among them, the prestressed steel strand A9 is tensioned along the hypotenuse direction of the triangular outer rib plate and triangular inner rib plate (corresponding ducts are arranged on the upper annular beam between the triangular outer rib plate and triangular inner rib plate to connect the ducts on the triangular outer rib plate and triangular inner rib plate), and the prestressed steel strand B10 is tensioned radially (i.e., along the bottom edge direction of the triangular outer rib plate and triangular inner rib plate).

[0086] The basic center area is concreted on-site after the prestressing construction is completed.

[0087] In addition, at the position corresponding to the door opening 305 on the concrete fan foundation, there is also a stairway 7. The stairway 7 is masoned on-site after the main structure of the foundation is assembled. There are stairway side walls 6 on both sides of the stairway 7, and the stairway side walls 6 are concreted on-site after the stairway 7 is masoned. The top of the stairway 7 is provided with a rain shelter 5 which is made of steel structure. The rain shelter 5 is fabricated in the factory and installed on-site (the rain shelter 5 is supported on the stairway side walls 6).

[0088] This concrete fan foundation is used for onshore wind power foundations. Since it is prefabricated in the factory and constructed in a fully assembled manner, the connection between segments is simple. Therefore, the on-site assembly is fast. Compared with the cast-in-situ wind power foundation, the construction period can be saved by 15 - 20 days. Using a prestressed concrete structure, compared with the ordinary reinforced concrete cast-in-situ foundation, the concrete consumption can be saved by 10% - 20%, and the steel consumption can be saved by 20% - 30%.

[0089] Embodiment 2:

[0090] Based on the above Embodiment 1, this embodiment provides an installation method for this concrete fan foundation.

[0091] S1: First, process each precast component in the factory, and then transport each precast component to the site;

[0092] S2: Assemble the main body of the fan foundation on-site:

[0093] During assembly, adopt an assembly sequence from the inside out: First, assemble the inner ring of the foundation, that is, butt each inner ring assembly 4 circumferentially, and connect adjacent inner ring assemblies 4 through cast-in-situ wet joints 8; then, assemble the foundation pedestal outside the inner ring of the foundation, that is, butt each pedestal assembly 3 circumferentially, and connect adjacent pedestal assemblies 3 through cast-in-situ wet joints 8; at the same time, connect the pedestal assembly 3 and the inner ring assembly 4 radially through cast-in-situ wet joints 8; then, assemble the middle ring of the foundation outside the foundation pedestal, that is, butt each middle ring assembly 2 circumferentially, and connect adjacent middle ring assemblies 2 through cast-in-situ wet joints 8; at the same time, connect the middle ring assembly 2 and the pedestal assembly 3 radially through cast-in-situ wet joints 8; finally, assemble the outer ring of the foundation outside the middle ring of the foundation, that is, butt each outer ring assembly 1 circumferentially, and connect adjacent outer ring assemblies 1 through cast-in-situ wet joints 8; at the same time, connect the outer ring assembly 1 and the middle ring assembly 2 radially through cast-in-situ wet joints 8;

[0094] S3: Tension the prestressed steel strands:

[0095] After the main body of the fan foundation is assembled, install and tension the prestressed steel strands in the prestressed duct A104; one end of the prestressed steel strand is located outside the main body of the fan foundation, and the other end passes through the prestressed duct A104 and enters the central area of the foundation; the prestressed steel strands are tensioned unidirectionally or symmetrically, and after tensioning, the anchor heads are sealed, and the prestressed duct A104 is grouted.

[0096] S4: Pour concrete on-site in the central area of the foundation.

[0097] S5: Mason the ladder 7 on-site at the position corresponding to the door opening 305. After the ladder 7 is masoned; mason the ladder side walls 6 on both sides of the ladder 7, and install the awning 5 on the top of the ladder 7. The awning 5 is supported on the ladder side walls 6.

[0098] When processing and installing the concrete fan foundation, the following requirements shall be ensured:

[0099] (1) Processing of precast components: The precast components shall ensure accurate dimensions, smooth concrete surfaces, and no quality problems such as honeycombing and pockmarks; the specifications, dimensions, and positions of the steel bars protruding from the precast component surfaces shall be accurate to ensure the smooth construction of the cast-in-place wet joints.

[0100] (2) Assembly of precast components: A cushion layer shall be set at the bottom of the foundation, and the top of the cushion layer shall be flat, meeting the accuracy requirements; the assembly sequence of the precast components shall follow the principle of "first internal components, then external components, first main components, then secondary components".

[0101] (3) Key points for prestress implementation: Unilateral tensioning or symmetrical tensioning can be adopted. For stress balance during tensioning, symmetrical tensioning is adopted (tensioning at the inner center ring position inside); for convenient tensioning, unilateral tensioning is adopted; during the construction of the cast-in-place wet joint, attention shall be paid to embedding prestress ducts, and the prestress ducts shall be firmly connected to the prestress ducts of the precast part.

[0102] (4) Treatment of the area around the foundation and the excavation surface: To improve the overall stability of the foundation, the area between the top of the outer ring beam of the foundation and the excavation slope of the foundation pit shall be filled with rubble concrete.

[0103] (5) Main technical points for foundation backfilling: The foundation backfilling material shall adopt materials with good water permeability such as sandy soil and gravel soil, and be compacted in layers. For local narrow areas, small mechanical compaction shall be adopted.

[0104] (6) Main measures to prevent local stress concentration: When external prestress is adopted for the upper tower barrel, a prestress anchorage end shall be set at the position of the upper ring beam, and an anchor backing plate and local bearing steel bars shall be set at the anchorage position to solve the stress concentration problem.

[0105] Although the present invention has been described in detail with general descriptions and specific embodiments above, based on the present invention, some modifications or improvements can be made, which are obvious to those skilled in the art. Therefore, these modifications or improvements made without departing from the spirit of the present invention all fall within the scope of protection required by the present invention.

Claims

1. A rib plate assembled prestressed concrete fan foundation, characterized in that: It includes a basic outer ring, a basic middle ring, a basic pedestal and a basic inner ring which are connected in sequence from the outside to the inside along the radial direction; The basic outer ring comprises a plurality of arc-shaped outer ring assemblies (1) which are connected in sequence along the circumferential direction; The basic middle ring comprises a plurality of arc-shaped middle ring assemblies (2) which are connected in sequence along the circumferential direction; The basic pedestal comprises a plurality of arc-shaped pedestal assemblies (3) which are connected in sequence along the circumferential direction; The basic inner ring comprises a plurality of arc-shaped inner ring assemblies (4) which are connected in sequence along the circumferential direction; The outer ring assembly (1), the middle ring assembly (2), the pedestal assembly (3) and the inner ring assembly (4) are all prefabricated parts; The outer circumferential surface and the inner circumferential surface of the base seat are both provided with radial support ribs spaced apart in the circumferential direction; the interior of the support ribs is provided with prestressed steel strands for tensioning.

2. The rib plate assembled prestressed concrete fan foundation according to claim 1, characterized in that: The inner ring of the foundation is provided with an inner reinforcement ring, the center of the inner reinforcement ring is the central area of ​​the foundation, and the central area of ​​the foundation is cast on site with concrete.

3. The rib plate assembled prestressed concrete fan foundation according to claim 1 or 2, characterized in that: The outer ring assembly (1) comprises: a prefabricated outer ring bottom plate (101), a prefabricated foundation outer ring beam (102) and a prefabricated outer ring rib plate (103); The prefabricated outer ring rib plate (103) is vertically arranged at the middle position of the prefabricated outer ring bottom plate (101) in the arc length direction, and the prefabricated outer ring rib plate (103) extends radially along the prefabricated outer ring bottom plate (101) and has the same width as the prefabricated outer ring bottom plate (101); The prefabricated foundation outer ring beam (102) is vertically arranged on the outer edge of the prefabricated outer ring bottom plate (101) and has the same arc length as the prefabricated outer ring bottom plate (101); the prefabricated foundation outer ring beam (102) protrudes from the prefabricated outer ring bottom plate (101), and the outer end of the prefabricated outer ring rib plate (103) is butt-jointed with the prefabricated foundation outer ring beam (102); the prefabricated foundation outer ring beams (102) of all the outer ring assemblies (1) are butt-jointed along the circumferential direction to form an integral outer ring beam.

4. The rib plate assembled prestressed concrete fan foundation according to claim 3, characterized in that: The middle ring assembly (2) comprises: a prefabricated middle ring bottom plate (201), a prefabricated middle ring rib plate A (202) and a prefabricated middle ring rib plate B (203); The prefabricated middle ring rib plate B (203) is vertically arranged at the middle position of the prefabricated middle ring bottom plate (201) in the arc length direction, and the prefabricated middle ring rib plate B (203) extends radially along the prefabricated middle ring bottom plate (201), and the radial outer end is butted with the inner end of the prefabricated outer ring rib plate (103); The prefabricated center ring rib plate A (202) is in an arc shape concentric with the prefabricated center ring bottom plate (201), and is arranged in the middle position of the prefabricated center ring bottom plate (201) in the width direction; after the center ring assemblies (2) are butt-jointed in the circumferential direction, the prefabricated center ring rib plate A (202) is butt-jointed in the circumferential direction to form a ring shape.

5. The rib plate assembled prestressed concrete fan foundation according to claim 4, characterized in that: The pedestal assembly (3) comprises: a prefabricated pedestal base plate (301), an internal side wall unit (302) and an upper beam unit (303); The internal side wall unit (302) is vertically arranged on the prefabricated pedestal bottom plate (301), the internal side wall unit (302) is an arc-shaped structure, and the internal side wall units (302) on all pedestal assemblies (3) are connected in sequence along the circumferential direction to form an annular internal side wall; The upper beam unit (303) is an arc-shaped structure, coaxially butted to the upper end surface of the internal side wall unit (302), and the upper beam units (303) on all the pedestal assemblies (3) are butted in sequence along the circumferential direction to form an upper annular beam; a plurality of prestressed holes B (304) are distributed at intervals along the circumferential direction on the end surface of each upper beam unit (303); The prefabricated outer ring rib plate (103) and the prefabricated middle ring rib plate B (203) are connected one by one to the rib plate connecting seats on the outer circumferential surface of the inner side wall unit (302) and the upper beam unit (303) to form an external supporting rib plate.

6. The rib plate assembled prestressed concrete fan foundation according to claim 5, characterized in that: The inner ring assembly (4) comprises: a prefabricated inner ring bottom plate (401), a prefabricated inner ring rib plate A (402) and a prefabricated inner ring rib plate B (403); The prefabricated inner ring rib plate B (403) is vertically arranged in the middle position of the prefabricated inner ring bottom plate (401) in the arc length direction. The prefabricated inner ring rib plate B (403) extends radially along the prefabricated inner ring bottom plate (401) and is connected to the rib plate connecting seats on the inner circumferential surface of the internal side wall unit (302) and the upper beam unit (303) to form an internal supporting rib plate; The prefabricated inner ring rib A (402) is vertically arranged on the inner edge of the prefabricated inner ring bottom plate (401) and has the same arc length as the prefabricated inner ring bottom plate (401); the inner end of the prefabricated inner ring rib B (403) is butt-jointed with the prefabricated inner ring rib A (402); after the prefabricated inner ring ribs A (402) are butt-jointed along the circumferential direction, an internal reinforcement ring is formed.

7. The rib plate assembled prestressed concrete fan foundation according to claim 6, characterized in that: Two upper and lower prestressed holes A (104) are arranged on the circumferential surface of the prefabricated foundation outer ring beam (102) at positions corresponding to the prefabricated outer ring rib plate (103); The prestressed hole A (104) located at the top penetrates the support ribs at corresponding positions on the outer circumferential surface and the inner circumferential surface of the base seat along the oblique direction of the support ribs; the prestressed hole A (104) located at the bottom penetrates the support ribs at corresponding positions on the outer circumferential surface and the inner circumferential surface of the base seat along the radial direction; The prestressed hole A (104) is used to install and tension the prestressed steel strand; one end of the prestressed steel strand is located outside the wind turbine foundation, and the other end passes through the prestressed hole A (104) and enters the central area of ​​the foundation.

8. The rib plate assembled prestressed concrete fan foundation according to claim 5, 6 or 7, characterized in that: A door opening (305) is provided on the inner side wall unit (302) of one of the pedestal assemblies (3); A stairway (7) is also provided at a position corresponding to the door opening (305), and stairway side walls (6) are provided on both sides of the stairway (7).

9. A method for installing a rib-assembled prestressed concrete fan foundation, characterized in that: The fan foundation is a rib plate assembled prestressed concrete fan foundation as described in any one of claims 1 to 8, characterized in that: S1: First, complete the processing of each prefabricated component in the factory, and then transport each prefabricated component to the site; S2: Assemble the main body of the fan foundation on site: When assembling, use the assembly order from inside to outside: First, the inner ring of the foundation is assembled, that is, each inner ring assembly (4) is butt-jointed along the circumferential direction, and adjacent inner ring assemblies (4) are connected by cast-in-place wet joints (8); Then, the foundation pedestal is assembled on the outside of the inner ring of the foundation, that is, each pedestal assembly (3) is butted together along the circumferential direction, and adjacent pedestal assemblies (3) are connected by cast-in-place wet joints (8); at the same time, the pedestal assembly (3) and the inner ring assembly (4) are connected radially by cast-in-place wet joints (8); Then, the middle ring of the foundation is assembled on the outside of the foundation pedestal, that is, each middle ring assembly (2) is butted together along the circumferential direction, and adjacent middle ring assemblies (2) are connected by cast-in-place wet joints (8); at the same time, the middle ring assembly (2) and the pedestal assembly (3) are connected radially by cast-in-place wet joints (8); Finally, the outer ring of the foundation is assembled on the outside of the middle ring of the foundation, that is, the outer ring assemblies (1) are butt-jointed along the circumferential direction, and the adjacent outer ring assemblies (1) are connected by cast-in-place wet joints (8); at the same time, the outer ring assemblies (1) are connected to the middle ring assemblies (2) along the radial direction by cast-in-place wet joints (8); S3: Tensioned prestressed steel strand: A prestressed steel strand is installed in the prestressed hole A (104) and tensioned; one end of the prestressed steel strand is located outside the main body of the wind turbine foundation, and the other end passes through the prestressed hole A (104) and enters the central area of ​​the foundation; after tensioning, the anchor is sealed and grouting is performed in the prestressed hole A (104). S4: Concrete is poured on site in the center area of ​​the foundation.

10. The installation method of the rib plate assembled prestressed concrete fan foundation according to claim 9, characterized in that: The prestressed steel strands are tensioned on one side or symmetrically.

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