CN115839102A - Wind power tower prestress stiffening type steel concrete high-rise pile cap foundation - Google Patents

Abstract

The invention provides a prestressed stiffened steel concrete high pile cap foundation of a wind power tower, which comprises a rock-socketed pile foundation, a steel cap, post-cast concrete of the cap and a prestressed device, wherein the bottom of the rock-socketed pile foundation is of a hollow interlayer steel pipe reinforced concrete structure, the steel cap is of a hollow interlayer steel pipe concrete structure, four corner shoe beams are arranged at the bottom of the steel cap, the post-cast concrete of the cap coats the four corner shoe beams at the bottom of the steel cap to fix the bottom of the steel cap and the top of the rock-socketed pile foundation, and a plurality of groups of prestressed devices are arranged in the post-cast concrete of the cap to increase the integrity of the steel cap and the post-cast pile foundation at the lower part.

Description

Wind power tower prestress stiffening type steel concrete high-rise pile cap foundation

Technical Field

The invention belongs to the technical field of civil engineering, and particularly belongs to a wind power tower prestress stiffening type steel concrete high pile cap foundation.

Background

The physical and mechanical properties of soil layers of a sea area accumulation layer and a flood accumulation layer are poor, the bearing capacity is low, the thickness distribution is uneven, the distribution of a petrochemical stratum in a lower layer is irregular, the fluctuation change is large, and the high-pile concrete bearing platform foundation is suitable for being adopted.

The traditional high-pile bearing platform foundation consists of a steel pipe pile foundation and a reinforced concrete bearing platform, wherein connecting steel bars are arranged at the top of the steel pipe pile and welded with a reinforcement framework inside the bearing platform, stiffening ribs are arranged at the bottom of a steel tower cylinder and embedded parts are embedded into concrete of the bearing platform, and the traditional high-pile bearing platform foundation adopts the steel pipe pile foundation, so that when a tower cylinder at the upper part of offshore wind power is high and the weight of a fan is large, a large number of steel pipe piles are required to be adopted to increase the bearing capacity of the foundation, and meanwhile, the top of the steel pipe pile is connected with the reinforcement framework inside the bearing platform through the connecting steel bars, so that the connection performance is greatly influenced by the marine environment, and the connection degradation is easily caused; because the bottom of the steel tower barrel is integrally embedded into the concrete bearing platform, the anchoring force of the tower barrel and the bearing platform is increased only by the stiffening ribs welded at the bottom of the tower barrel and the embedded parts, so that stress concentration is easily generated at the joint of the tower barrel and the bearing platform, the annular concrete of the tower barrel is cracked in a large range, and the service life of the offshore wind power equipment is shortened by the factors.

Disclosure of Invention

In order to solve the problems in the prior art, the invention provides a wind power tower prestress stiffening type steel concrete high-pile bearing platform foundation which is used for solving the problem that stress concentration is serious due to small contact area of the bottom of a tower cylinder and bearing platform concrete under cooperative stress, and avoiding the problems that the joint of the tower cylinder and the bearing platform concrete is easy to crack and the like.

In order to achieve the purpose, the invention provides the following technical scheme: the utility model provides a wind power tower prestressing force stiffening type steel concrete high pile cap basis, waters concrete and prestressing force device behind the pile foundation that inlays, shaped steel cushion cap, the pile foundation bottom is cavity intermediate layer steel pipe reinforced concrete structure, and the shaped steel cushion cap is cavity intermediate layer steel pipe concrete structure, and the shaped steel cushion cap bottom is provided with four corners boots roof beam, waters behind the cushion cap concrete cladding shaped steel cushion cap bottom four corners boots roof beam with shaped steel cushion cap bottom and the top of the pile foundation that inlays is fixed, and multiunit prestressing force device sets up and waters behind the cushion cap in the concrete and be used for increasing the wholeness of shaped steel cushion cap and lower part pile foundation that inlays.

Further, the rock-socketed pile foundation comprises a top bearing platform and a bottom pile foundation, the bottom pile foundations are fixedly connected to the bottom of the top bearing platform, the axes of the bottom pile foundations are outwards provided with inclination angles, and the inclination angles are 3-15 degrees;

the top bearing platform is a concrete bearing platform;

the bottom pile foundation is a hollow interlayer steel pipe reinforced concrete pile, and the distance between the hollow interlayer steel pipe reinforced concrete piles is at least 1.5 times of the pile diameter.

Further, the bottom pile foundation includes steel pipe in the pile foundation, pile foundation outer steel pipe and pile foundation intermediate layer reinforced concrete, and the steel pipe setting is in the outer steel pipe of pile foundation in the pile foundation, and pile foundation intermediate layer reinforced concrete is located the pile foundation inner steel pipe outer wall and the intermediate layer that the outer steel pipe inner wall of pile foundation constitutes, and in the outer steel pipe top embedding top cushion cap of pile foundation, bottom embedding basement rock.

Furthermore, the interlayer reinforced concrete comprises a spiral reinforcement cage and interlayer concrete, and the interlayer concrete is used for coating the spiral reinforcement cage;

the spiral steel bar framework comprises a framework main bar and a top increasing end, the bottom of the framework main bar is embedded into bedrock, the top increasing end is connected with the bottom of the top bearing platform, and the top increasing end is required to be integrally embedded into the top bearing platform connected with the top increasing end.

Further, the shaped steel cushion cap includes a tower section of thick bamboo and sets up the rigid flange at tower section of thick bamboo top, and a tower section of thick bamboo is the cavity intermediate layer steel pipe concrete tower section of thick bamboo, and tower section of thick bamboo bottom is provided with four corners boots roof beam, and tower section of thick bamboo bottom and four corners boots roof beam bottom all anchor with the rock-socketed pile foundation top.

Further, the tower cylinder comprises a tower cylinder inner steel tube, a tower cylinder outer steel tube and tower cylinder barrel clamp layer concrete, wherein the tower cylinder inner steel tube is arranged in the tower cylinder outer steel tube, and the tower cylinder barrel clamp layer concrete is arranged in an interlayer formed by the outer wall of the tower cylinder inner steel tube and the inner wall of the tower cylinder outer steel tube;

the inside diameter of ring flange of rigid flange is the same width with the interior steel pipe diameter of a tower section of thick bamboo, and ring flange outside diameter is greater than the outer steel pipe diameter of a tower section of thick bamboo, and the ring flange bottom is provided with ring flange stiffening rib, and ring flange stiffening rib both right-angle sides are welded with ring flange bottom terminal surface and the outer wall welding of the outer steel pipe of a tower section of thick bamboo respectively.

Furthermore, four corner boot beams are four boot beams connected in a circular arc chamfer transition mode, the four boot beams are respectively arranged in four directions at the bottom of the tower barrel, the boot beams are made of wide-flange H-shaped steel, one side of the wide-flange H-shaped steel is connected with the outer wall of the section steel bearing platform, anchor rod pore passages are formed in the wide-flange H-shaped steel and used for setting anchor rods penetrating through the upper flange and the lower flange, multiple rows of rivets are arranged on the top surface of the wide-flange H-shaped steel at equal intervals, and short edges of the wide-flange H-shaped steel in parallel in arrangement direction are arranged.

Furthermore, a longitudinal stiffening rib is arranged in the wide-flange H-shaped steel in parallel with the upper flange and the lower flange, the size of the longitudinal stiffening rib is the same as that of the flange of the wide-flange H-shaped steel, and a plurality of transverse stiffening ribs are arranged in the wide-flange H-shaped steel in a manner of being perpendicular to the upper flange and the lower flange at intervals.

Further, still include the U-shaped reinforcing bar, the U-shaped reinforcing bar is obtained through two vertical reinforcing bars and the combination of a horizontal reinforcement of being connected with two vertical reinforcing bar tops, and the bottom and the embedded rock pile foundation top anchor of two vertical reinforcing bars, the whole cladding of U-shaped reinforcing bar is in the cushion cap post-cast concrete, and the U-shaped reinforcing bar is along boots roof beam length limit direction equidistant at least three.

Furthermore, the prestressing force device sets up four groups, and four groups prestressing force devices are arranged along hoop interval 90, and every group is equipped with three prestressing force stretch-draw end, and prestressing force device includes tip ground tackle and prestressing steel, and prestressing steel one end fastening is at the embedded rock pile foundation top, sets up the prestressing force pore canal in the cushion cap post-poured concrete, and the prestressing steel other end carries out single-end stretch-draw in the prestressing force pore canal through the tip ground tackle.

Compared with the prior art, the invention has at least the following beneficial effects:

the invention provides a wind power tower prestress stiffening type steel concrete high pile cap foundation, which adopts a rock-socketed pile foundation with a hollow interlayer steel pipe reinforced concrete structure and a combined type cap structure combined with a steel cap with a hollow interlayer steel pipe concrete structure, adopts a hollow interlayer structure, and can effectively reduce the dead weight of the structure; the excellent resistance to compression and bending resistance of shaped steel cushion cap cavity intermediate layer steel pipe concrete structure has been fully utilized to the cushion cap structure to set up four corners boots roof beam and increased the area of contact of atress in coordination with the rock-socketed pile foundation in shaped steel cushion cap bottom. Under the action of strong wind load, the compression contact area of the rock-socketed pile foundation and the profile steel bearing platform is increased by the compression side through the four-corner shoe beam, the compression performance of the rock-socketed pile foundation can be fully exerted, the drawing force generated at the joint of the profile steel bearing platform is dispersed by the tension side through the four-corner shoe beam, the pre-pressing is provided for the four-corner shoe beam by pouring concrete load after the bearing platform is poured, the deformation of the four-corner shoe beam is effectively controlled, the tensile stress at the joint of the concrete bearing platform and the tower barrel is effectively reduced, the cracking of concrete of the bearing platform is effectively avoided, and the durability of the bearing platform foundation is further improved; the pre-stress provided by the plurality of groups of pre-stress devices firmly fixes the section steel bearing platform between two layers of concrete by increasing the contact pressure between the rock-socketed pile foundation and the post-cast concrete, the compressive stress can effectively balance the tensile stress at the top of the section steel bearing platform and the rock-socketed pile foundation caused by the horizontal load at the upper part, the concrete cracking of the bearing platform is avoided, meanwhile, the magnitude of the pre-stress can increase the transverse deformation rigidity, and the pre-stress can be increased in a proper range for the bearing platform with the anti-collision requirement according to the design requirement; the bearing platform foundation structure has strong structural integrity, all parts are mutually matched, the performance advantages of concrete compression resistance and steel tensile strength are fully exerted, and meanwhile, the bearing platform foundation structure is convenient to construct, easy to assemble and good in practicability and engineering application value.

The existing high pile cap foundation mostly adopts a steel pipe pile foundation filled with concrete, the hollow interlayer structure is adopted, the self weight of the structure can be effectively reduced, the spiral reinforcement cage is arranged in the interlayer concrete, the anchoring capability of a pile body and the foundation can be increased, meanwhile, the cross section of the top of the spiral reinforcement cage is increased, the embedding capability with the top cap can be increased, the reinforced concrete wrapped by the inner steel pipe and the outer steel pipe has higher bearing performance than that of the simply poured concrete, and the hollow interlayer concrete has the advantages of reducing the using amount of the inner steel material and the outer steel material and improving the structural economy. When there is great level and vertical load effect in the upper load, the load passes through pile foundation top cushion cap concrete and transmits to the pile body, hollow sandwich structure has reduced the distribution area of concrete, the cross sectional area of steel pipe has been increased, cross-section bending resistance and antitorque inertia moment have been improved, can effectively share the each direction load effect of upper portion load, avoid taking place inefficacy because of the pile foundation bearing capacity is not enough, set up spiral reinforcement framework in the concrete and can increase the anchoring ability of pile foundation and stratum when horizontal load is great, because of the tensile stress that the outer steel pipe of hollow intermediate layer reinforced concrete pile foundation more is close to the cross-section center and bears of steel bar distribution position is obviously less than outer steel pipe of hollow intermediate layer reinforced concrete pile foundation.

According to the bearing platform foundation, the structural steel tower barrel structure is used as a connecting device of the bearing platform and the wind power upper structure, and the core hollow sandwich steel tube concrete tower barrel in the center of the structural steel tower barrel can fully exert excellent axial bearing performance and lateral bending resistance of the hollow sandwich steel tube concrete structure; the boots roof beam has set up the boots roof beam bottom and has increased the atress area of contact in coordination with the cushion cap concrete, and boots roof beam upside has set up the anchor effect that U-shaped reinforcing bar increased top cushion cap and boots roof beam, and the tensile stress distributes in the abundant reduction concrete, has effectively avoided concrete top cushion cap fracture.

The anchorage device at one side of the prestress tensioning end of the prestress device is buried at the top of the rock-socketed pile foundation, the structure can be pre-pressed in a single-end tensioning mode after the construction of pouring concrete after the bearing platform is finished, the integrity of the steel reinforced concrete bearing platform and the pile group structure at the lower part is increased due to the arrangement of the prestress device, and meanwhile, the application of the prestress is favorable for reducing the tension stress in the concrete of the bearing platform under the strong wind load and slowing down the cracking of the concrete.

The flange plate is arranged at the top of the section steel bearing platform, the stiffening ribs are arranged at the bottom of the flange and used for increasing the compressive rigidity of the flange plate, and the top surface of the flange is flush with the top surface of the section steel tower cylinder, so that the flange is convenient to assemble and connect with the tower cylinder section at the upper part of the wind power tower, the construction efficiency of the wind power tower is improved, and the field wet operation is reduced.

Drawings

FIG. 1 is a perspective view of the present invention construction;

FIG. 2 is a vertical cross-sectional view of the present invention

FIG. 3 is a structural view of a section steel platform according to the present invention;

FIG. 4 is a bottom pile construction drawing of the present invention;

FIG. 5 is a bottom cross-sectional view and a vertical cross-sectional view of the bottom pile foundation of the present invention;

in the drawings: 1-rock-socketed pile foundation, 100-top bearing platform, 101-bottom pile foundation, 1011-pile foundation inner steel pipe, 1012-pile foundation outer steel pipe, 1013-interlayer reinforced concrete, 1014-spiral steel bar framework, 10141-framework main bar, 10142-stirrup, 10143-top enlarged end, 1015-sandwich concrete, 2-section steel bearing platform, 201-tower drum, 2011-tower drum inner steel pipe, 2012-tower drum outer steel pipe, 2013-tower collet sandwich concrete, 202-four corner shoe beam, 2021-wide flange H-shaped steel, 2020-H section steel flange, 20211-H section steel web, 20212-longitudinal stiffening rib, 20213-transverse stiffening rib, 2022-anchor rod, 2023-U-shaped steel bar, 2024-rivet, 203-rigid flange, 2031-flange plate, 2032-flange stiffening rib, 2033-flange connecting hole, 3-bearing platform post-poured concrete, 4-prestressing device, 401-prestressing steel and 402-pile reinforcement.

Detailed Description

The invention is further described with reference to the following figures and detailed description.

The invention provides a wind power tower prestress stiffening type steel concrete high pile cap foundation which is applied to offshore wind power and comprises a rock-socketed pile foundation 1, a steel cap foundation 2, a cap post-cast concrete 3 and prestress devices 4, wherein the steel cap foundation 2 is arranged at the top of the rock-socketed pile foundation 1, the cap post-cast concrete 3 coats the bottom of the steel cap foundation 2 to fix the bottom of the steel cap foundation 2 and the top of the rock-socketed pile foundation 1, and the top of the cap post-cast concrete 3 is also provided with a plurality of groups of prestress devices 4 for improving the integrity of the steel cap foundation 2 and the lower rock-socketed pile foundation 1.

As shown in fig. 4 to 5, the rock-socketed pile foundation 1 of the present invention includes a top pile cap 100 and a plurality of bottom pile foundations 101 fixedly connected to the top pile cap 100, the top pile cap 100 is a concrete pile cap, the bottom pile foundations 101 are hollow steel pipe reinforced concrete piles with an interlayer, the bottom pile foundations 101 are in pile group form, the axis of the bottom pile foundations 101 is provided with an inclination outward, the diameter of the pile body of the bottom pile foundations 101 needs to meet the design requirement of bearing capacity, and generally 8 pile foundations are provided;

preferably, bottom pile foundation 101 includes steel pipe 1011 in the pile foundation, outer steel pipe 1012 of pile foundation and pile foundation intermediate layer reinforced concrete 1013, and steel pipe 1011 sets up in outer steel pipe 1012 of pile foundation in the pile foundation, and pile foundation intermediate layer reinforced concrete 1013 is arranged in the intermediate layer that steel pipe 1011 outer wall and outer steel pipe 1012 inner wall of pile foundation constitute and closely laminates, bonds with inside and outside steel pipe, and during steel pipe 1012 top embedding top cushion cap 100 outside the pile foundation, the bottom embedded bedrock.

Preferably, the wall thickness of the outer steel pipe 1012 of the pile foundation needs to meet the requirement of corrosion thickness, and in order to ensure that the rock-socketed pile foundation 1 has enough bearing capacity, the depth of the outer steel pipe 1012 of the pile foundation buried in the rock stratum needs to meet the requirement of standard design.

The interlayer reinforced concrete 1013 comprises a spiral steel bar framework 1014 and interlayer concrete 1015, wherein the interlayer concrete 1015 is used for coating the spiral steel bar framework 1014 and needs to meet the thickness requirement of a steel bar protection layer; the spiral steel bar framework 1014 is embedded into bedrock at the bottom.

The spiral steel bar framework 1014 comprises a framework main bar 10141, a stirrup 10142 and a top increasing end 10143, wherein the framework main bar 10141 needs to meet the design requirement of the bearing capacity of a pile foundation, and in order to ensure that the rock-socketed pile foundation 1 has enough bearing capacity, the depth of the bottom of the framework main bar 10141 embedded into a rock stratum needs to meet the standard design requirement; the stirrups 10142 are arranged on the framework main reinforcement 10141, the arrangement distance of the stirrups 10142 needs to meet the standard requirement, and the steel consumption can be reduced on the premise of fully exerting the stirrup constraint effect; the top enlarged end 10143 is connected with the bottom of the top bearing platform 100, and the top enlarged end 10143 is required to be integrally embedded into the top bearing platform 100 connected with the top enlarged end;

preferably, the inclination angle of the bottom pile foundation 101 is generally 3-15 degrees, and 5-10 degrees is recommended; the spacing between the bottom pilings 101 must be at least 1.5 times the diameter of the bottom pilings 101.

As shown in fig. 3, the section steel bearing platform 2 of the present invention includes a tower 201, a four-corner shoe beam 202, and a rigid flange 203, the rigid flange 203 is disposed on the top of the tower 201, the bottom of the tower 201 is welded with the four-corner shoe beam 202, the bottom of the tower 201 and the bottom of the four-corner shoe beam 202 are both anchored with the upper end surface of the top bearing platform 100, and the bearing platform post-cast concrete 3 integrally coats the four-corner shoe beam 202.

Preferably, tower section of thick bamboo 201 is a cavity intermediate layer steel pipe concrete tower section of thick bamboo, including steel pipe 2011, the outer steel pipe 2012 of tower section of thick bamboo and tower section of thick bamboo collet chuck layer concrete 2013 in the tower section of thick bamboo, steel pipe 2011 sets up in the outer steel pipe 2012 of tower section of thick bamboo in the tower section of thick bamboo, tower section of thick bamboo collet chuck layer concrete 2013 sets up in the intermediate layer that steel pipe 2011 outer wall and the outer steel pipe 2012 inner wall of tower section of thick bamboo constitute in the tower section of thick bamboo and closely laminate, bond with inside and outside steel pipe.

Preferably, the four corner shoe beams 202 are four shoe beams connected in an arc chamfer transition manner, the four shoe beams are respectively arranged in four directions at the bottom of the tower barrel 201, each shoe beam comprises a wide-flange H-shaped steel 2021, an anchor rod 2022, a U-shaped steel bar 2023 and a rivet 2024, an H-shaped steel web 20211 is arranged in the wide-flange H-shaped steel 2021, and the wide-flange H-shaped steel beams are welded with the tower barrel outer steel pipe 2012 through an H-shaped steel flange 20210 and an H-shaped steel web 20211; the wide-flange H-shaped steel 2021 is provided with an anchor rod hole channel for arranging an anchor rod 2022 penetrating through upper and lower flanges on the wide-flange H-shaped steel 2021, rivets 2024 are arranged at four corners of the four-corner boot beam 202 and welded to the top surface of the wide-flange H-shaped steel 2021, and are arranged in a plurality of rows at equal intervals, wherein the arrangement direction is parallel to the short side of the H-shaped steel flange 20210;

a plurality of U-shaped steel bars 2023 are arranged on the shoe beam in parallel at intervals, the U-shaped steel bars 2023 are obtained by combining two vertical steel bars and one horizontal steel bar connected with the tops of the two vertical steel bars, the bottom ends of the two vertical steel bars are anchored in the top bearing platform 100, and the U-shaped steel bars 2023 are integrally coated in the post-cast concrete 3 of the bearing platform;

preferably, U-shaped reinforcement 2023 is arranged along H shaped steel edge 2020 long limit direction equidistant, proposes to specifically choose for use according to wind power tower height and arranges the quantity, for satisfying that shaped steel cushion cap 2 has sufficient anchoring ability with the rock-socketed pile foundation 1, U-shaped reinforcement 2023 arranges 3 at least at the interval on the four corners of four corners boots roof beam 202 respectively.

Preferably, the middle part of the wide-flange H-shaped steel 2021 is provided with a longitudinal stiffening rib 20212 and a transverse stiffening rib 20213 which have the same thickness and width as the H-shaped steel flange 20210, one end of the longitudinal stiffening rib 20212 is welded with the tower tube 2012 outside the tower, the transverse stiffening rib 20213 is welded with the H-shaped steel flange 20210, and the joint is interrupted at the passing part of the longitudinal stiffening rib 20212, so that the requirement of intersecting the longitudinal stiffening rib and the transverse stiffening rib in the steel structure specification is met during setting;

preferably, the arrangement of the anchor 2022 includes two types, specifically: the four-corner boot beam 202 and the tower barrel 201 are arranged in an annular manner at the joint and are positioned at the four corners of the four-corner boot beam 202 and are arranged in parallel with the short edge of the H-shaped steel;

the prestressed reinforcement device 4 comprises an end anchorage 401 and a prestressed reinforcement 402, wherein the prestressed reinforcement 402 is fastened in concrete through an anchorage arranged in a top bearing platform 100, and the prestressed reinforcement tensioning is completed in a prestressed pore channel arranged at the top of the post-cast concrete 3 of the bearing platform in a single-end tensioning mode.

Preferably, 4 groups are arranged on each prestress device 4, each group of prestress devices 4 is arranged at 90 degrees along the circumferential direction, each group is provided with 3 prestress tensioning ends, the prestress tensioning ends are located on the post-cast concrete layer 3, the prestress tensioning ends are selected from end anchorage devices 401 and are not less than 6 prestress anchoring holes, and anchoring of the end anchorage devices 401 is required after the prestress steel bars 402 are tensioned.

The internal diameter of a flange plate 2031 of the rigid flange 203 is as wide as the diameter of a steel pipe 2011 in a tower, the external diameter of the flange plate 2031 is 200-300 mm larger than the diameter of a steel pipe 2012 outside the tower, a flange plate stiffening rib 2032 is arranged at the bottom of the flange plate 2031, and two right-angle sides of the flange plate stiffening rib 2032 are respectively welded with the end surface at the bottom of the flange plate 2031 and the outer wall surface of the steel pipe 2012 outside the tower.

The construction method of the high pile cap foundation comprises the following steps:

(1) The spiral steel bar framework 1014 of the bottom pile foundation 101 is respectively positioned with the inner steel pipe 1011 of the pile foundation and the outer steel pipe 1012 of the pile foundation by adopting a short steel bar welding method, so that the relative positions of the three are ensured to be consistent with the design, and the axes of the three need to meet the requirement that the spiral steel bar framework 1014, the inner steel pipe 1011 of the pile foundation and the outer steel pipe 1012 of the pile foundation are positioned on the same straight line.

(2) With fixed spiral reinforcement skeleton 1014, hoist to appointed mounted position with steel pipe 1011 and the outer steel pipe 1012 of pile foundation in the pile foundation, with skeleton owner muscle 10141 and the pre-buried income rock stratum in the outer steel pipe 1012 bottom of pile foundation, according to pile body design angle adjustment pile foundation mounted position, can pour intermediate layer concrete 1015 after accomplishing the pile foundation and burying work, obtain bottom pile foundation 101 when treating intermediate layer concrete 1015 satisfies the design strength requirement, carry out the construction of top cushion cap 100 after bottom pile foundation 101 possesses sufficient bearing capacity.

(3) When the top bearing platform 100 is constructed, a concrete pouring template is installed at the top of a pile foundation, the U-shaped steel bar 2023 is constructed by a segmented welding method, straight-bar steel bars and anchor rods 2022 on two sides of the U-shaped steel bar 2023 are pre-embedded into the top bearing platform 100, the section steel bearing platform 2 is hoisted after the concrete reaches the designed strength, the section steel bearing platform 2 and the four-corner shoe beams 202 are welded in advance, and anchor rod channels are reserved on the four-corner shoe beams 202.

(4) Hoisting equipment such as a floating crane is adopted to complete hoisting of the section steel bearing platform 2, the section steel bearing platform 2 is hoisted to a designated position, the anchor rod 2022 penetrates through an anchor rod hole channel reserved in the four-corner shoe beam 202, fixing of the anchor rod is completed in a nut or end welding mode, straight steel bars with the same diameter are welded with straight bars on two sides of the U-shaped steel bar, and sealing of the U-shaped steel bar 2023 is completed.

(5) After the hoisting and assembling work of the section steel bearing platform 2 is completed, the construction of post-bearing platform cast-in-place concrete 3 is completed in a mode of vertical template cast-in-place concrete, when the concrete is poured, the tensioning hole and the anchorage device installation position of the prestressed steel bars are reserved, after the post-bearing platform concrete reaches the design strength, the tensioning of 6 prestressed steel bars 402 is completed in the reserved prestressed steel bar tensioning hole in a single-side tensioning mode, the end parts of the prestressed steel bars are fixed by anchorage devices 401, and after the tensioning of all the prestressed steel bars is completed, the anchor sealing work of tensioning ends is completed at the anchorage device installation position.

The working principle of the invention is as follows:

the invention fully utilizes the excellent axial compression and bending resistance of the hollow sandwich steel pipe concrete, meanwhile, the hollow steel pipe structure is similar to the traditional steel pipe pile structure, and is convenient for positioning and constructing the pile body, on the basis, the spiral steel bar framework 1014 is arranged in the sandwich concrete, the anchoring capability between the pile body and the foundation can be increased, meanwhile, the section of the top of the spiral steel bar framework 1014 is enlarged, which is beneficial to increasing the embedding capability with the top bearing platform 100, the reinforced concrete wrapped by the inner and outer steel pipes has higher bearing performance than that of the simply poured concrete, and has advantages in reducing the using amount of the inner and outer steel materials and improving the economical efficiency of the structure, under the constraint action of the outer steel pipes, the sandwich reinforced concrete effectively improves the bearing performance of the pile foundation, and simultaneously improves the anti-buckling performance of the inner and outer steel pipes. When there is great level and vertical load effect in the upper portion load, the load passes through pile foundation top cushion cap concrete and transmits to the pile body, hollow sandwich structure has reduced the distribution area of concrete, the cross sectional area of steel pipe has been increased, cross-section bending resistance and antitorque inertia moment have been improved, can effectively share the load effect of each direction of upper portion load, avoid taking place inefficacy because of the pile foundation bearing capacity is not enough, set up spiral reinforcement framework 1014 in with the concrete can increase the anchor ability of pile foundation and stratum when horizontal load is great, because of the tensile stress that steel bar distribution position more closely the cross-section center than hollow intermediate layer reinforced concrete pile foundation outer steel pipe 1012 bears is obviously less than hollow intermediate layer concrete pile foundation outer steel pipe 1012.

The invention fully utilizes the performance advantages of concrete and steel, the four-corner shoe beam 202 is arranged at the bottom of the profile steel bearing platform 2, the contact area between the bottom of the original tower and the bearing platform is increased, under the action of upper load, the tower 201 of the profile steel bearing platform 2 bears almost all vertical load, the bottom area of the four-corner shoe beam 202 enlarges the distribution area of vertical pressure, when the upper load contains horizontal force, the stress state of the beam end of the four-corner shoe beam 202 is in a similar tension-compression stress mode, because the contact area between the bottom of the four-corner shoe beam 202 and the concrete of the pile foundation bearing platform is large, the concrete stress change of the pile foundation bearing platform is small, when the upper horizontal force component is further increased, the U-shaped reinforcing bars 2023 and the anchor rods 2023 at the upper parts of the four corners of the four-corner shoe beam 202 further restrict the shoe beam from tilting, and simultaneously, the load of the post-cast concrete 3 of the bearing platform provides pre-pressing for the four-corner shoe beam 202, the deformation of the four-corner shoe beam 202 is effectively controlled, the tension stress at the joint of the concrete bearing platform and the tower is effectively reduced, and the service life of the structure is obviously prolonged.

The anchorage device 401 is fixed in the pile foundation top bearing platform concrete 100 by reserving the installation positions of the anchorage device 401 and the prestressed reinforcement 402 in the pile foundation top bearing platform concrete, the prestressed reinforcement 402 is tensioned in a single-end tensioning mode in the prestressed reinforcement hole reserved at the top of the post-cast concrete 3 of the bearing platform to provide the prestressed stress for the section steel concrete bearing platform, the prestressed reinforcement 402 provides the prestressed stress to firmly fix the section steel bearing platform 2 between two layers of layers by increasing the contact pressure between the top bearing platform 100 and the post-cast concrete 3, the prestressed stress enables the top bearing platform 100 and the section steel bearing platform 2, and the section steel bearing platform 2 and the post-cast concrete 3 of the bearing platform to generate certain compressive stress, the tensile stress between the section steel bearing platform 2 and the top bearing platform 100 caused by upper horizontal load can be effectively balanced, the bearing platform concrete is prevented from cracking, meanwhile, the magnitude of the prestressed stress can increase the transverse deformation rigidity, and the stress can be increased in a proper range according to the design requirement for the bearing platform with the requirement of collision avoidance.

Claims (10)

1. The utility model provides a wind power tower prestressing force stiffening type steel concrete high pile cap basis, its characterized in that, including rock-socketed pile foundation (1), shaped steel cushion cap (2), cushion cap post-cast concrete (3) and prestressing force device (4), rock-socketed pile foundation (1) bottom is cavity intermediate layer steel pipe reinforced concrete structure, and shaped steel cushion cap (2) are cavity intermediate layer steel pipe concrete structure, and shaped steel cushion cap (2) bottom is provided with four corners boots roof beam (202), and concrete (3) cladding shaped steel cushion cap (2) bottom four corners boots roof beam (202) are fixed shaped steel cushion cap (2) bottom and the top of rock-socketed pile foundation (1) after the cushion cap, and multiunit prestressing force device (4) set up in concrete (3) are watered after the cushion cap and are used for increasing the wholeness of shaped steel cushion cap (2) and lower part rock-socketed pile foundation (1).

2. The wind power tower prestress stiffening steel concrete high pile cap foundation according to claim 1, wherein the rock-socketed pile foundation (1) comprises a top cap (100) and a bottom pile foundation (101), a plurality of bottom pile foundations (101) are fixedly connected to the bottom of the top cap (100), the axes of the plurality of bottom pile foundations (101) are provided with outward inclination angles, and the inclination angles are 3-15 degrees;

the top bearing platform (100) is a concrete bearing platform;

bottom pile foundation (101) are cavity intermediate layer steel pipe reinforced concrete pile, and the interval between a plurality of cavity intermediate layer steel pipe reinforced concrete piles is 1.5 times of stake footpath at least.

3. The wind power tower prestress stiffening steel concrete high pile cap foundation according to claim 2, wherein the bottom pile foundation (101) comprises a pile foundation inner steel tube (1011), a pile foundation outer steel tube (1012) and a pile foundation interlayer reinforced concrete (1013), the pile foundation inner steel tube (1011) is arranged in the pile foundation outer steel tube (1012), the pile foundation interlayer reinforced concrete (1013) is positioned in an interlayer formed by the outer wall of the pile foundation inner steel tube (1011) and the inner wall of the pile foundation outer steel tube (1012), the top of the pile foundation outer steel tube (1012) is embedded into the top cap (100), and the bottom of the pile foundation outer steel tube (1012) is embedded into a bedrock.

4. The wind power tower prestress stiffened steel concrete high pile cap foundation of claim 3, wherein the sandwich reinforced concrete (1013) comprises a spiral steel reinforcement framework (1014) and a sandwich concrete (1015), the sandwich concrete (1015) is used for coating the spiral steel reinforcement framework (1014);

spiral steel bar skeleton (1014) include skeleton owner muscle (10141) and top increase end (10143), and skeleton owner muscle (10141) bottom embedding bed rock, top increase end (10143) are connected with top cushion cap (100) bottom, and need with the whole embedding of top increase end (10143) in top cushion cap (100) of being connected with it.

5. The wind power tower prestress stiffening type steel concrete high pile cap foundation according to claim 1, characterized in that, the steel cap (2) comprises a tower (201) and a rigid flange (203) arranged at the top of the tower (201), the tower (201) is a hollow interlayer steel pipe concrete tower, a four corner shoe beam (202) is arranged at the bottom of the tower (201), and the bottom of the tower (201) and the bottom of the four corner shoe beam (202) are anchored with the top of the rock-socketed pile foundation (1).

6. The wind power tower prestress stiffened steel concrete high pile cap foundation as recited in claim 1, wherein the tower (201) comprises a tower inner steel tube (2011), a tower outer steel tube (2012) and tower collet laminated concrete (2013), the tower inner steel tube (2011) is arranged in the tower outer steel tube (2012), and the tower collet laminated concrete (2013) is arranged in an interlayer formed by the outer wall of the tower inner steel tube (2011) and the inner wall of the tower outer steel tube (2012);

the inside diameter of ring flange (2031) of rigid flange (203) and tower section of thick bamboo in steel pipe (2011) diameter aequilate, ring flange (2031) outside diameter is greater than tower section of thick bamboo outer steel pipe (2012) diameter, and ring flange (2031) bottom is provided with ring flange stiffening rib (2032), and two right-angle sides of ring flange stiffening rib (2032) weld with ring flange (2031) bottom terminal surface and tower section of thick bamboo outer steel pipe (2012) outer wall respectively.

7. The wind power tower prestress stiffening steel concrete high pile cap foundation according to claim 1, wherein the four corner shoe beams (202) are four shoe beams connected in a circular arc chamfer transition mode, the four shoe beams are respectively arranged in four directions at the bottom of the tower barrel (201), the shoe beams are wide-flange H-shaped steel (2021), one side of the wide-flange H-shaped steel (2021) is connected with the outer wall of the steel cap (2), anchor rod hole passages for arranging anchor rods (2022) penetrating through upper and lower flanges are arranged on the wide-flange H-shaped steel (2021), rivets (2024) are arranged on the top surface of the wide-flange H-shaped steel (2021) in multiple rows at equal intervals, and the arrangement direction is parallel to the short side of the wide-flange H-shaped steel (2021).

8. The wind power tower prestressed stiffened steel concrete high pile cap foundation of claim 7, wherein a longitudinal stiffening rib (20212) is arranged in the wide-flange H-section steel (2021) in parallel with the upper and lower flanges, the size of the longitudinal stiffening rib (20212) is the same as that of the flange of the wide-flange H-section steel (2021), and a plurality of transverse stiffening ribs (20213) are arranged in the wide-flange H-section steel (2021) at intervals in a direction perpendicular to the upper and lower flanges.

9. The wind power tower prestress stiffening steel concrete high pile cap foundation according to claim 7, characterized by further comprising U-shaped steel bars (2023), wherein the U-shaped steel bars (2023) are obtained by combining two vertical steel bars and a horizontal steel bar connected with the tops of the two vertical steel bars, the bottom ends of the two vertical steel bars are anchored with the top of the rock-socketed pile foundation (1), the U-shaped steel bars (2023) are integrally coated in the post-cast concrete (3) of the cap, and at least three U-shaped steel bars (2023) are arranged at equal intervals along the long side direction of the shoe beam.

10. The wind power tower prestress stiffening steel concrete high pile cap foundation according to claim 1, wherein the prestress devices (4) are arranged in four groups, the four groups of prestress devices (4) are arranged at intervals of 90 degrees in the circumferential direction, each group is provided with three prestress tensioning ends, each prestress device (4) comprises an end anchorage (401) and a prestress steel bar (402), one end of the prestress steel bar (402) is fastened at the top of the rock-socketed pile foundation (1), a prestress hole channel is arranged in the cap post-cast concrete (3), and the other end of the prestress steel bar (402) is subjected to single-end tensioning in the prestress hole channel through the end anchorage (401).

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