阅读说明：本技术 一种用于抗浮施工的预应力张拉结构及方法 (Prestress tensioning structure and method for anti-floating construction ) 是由 高作平 张畅 吴博 代艳辉 李志强 程海华 谭星舟 于 2021-08-24 设计创作，主要内容包括：本发明提出了一种用于抗浮施工的预应力张拉结构及方法,通过斜拉钢绞线,通过转向支座对跨中区施加一个向下的力,抵消向上浮力的影响；设置永久锚和两成品锚具构成的预应力张拉装置,方便快速张紧钢绞线,且锚固后非常牢固；本发明提供了对应的张拉装置,方便快捷,完成张拉后可以快速拆卸；本发明的张拉结构和方法,具有施工工期短,抗浮见效快的优点,所有施工作业均在防水板面进行,施工简便,无需钻穿防水板,施工不受水压力的影响,不会破坏现有防水层,无大型施工机械设备,现有地下室净空满足施工要求,适合大规模推广使用。(The invention provides a prestressed tensioning structure and a method for anti-floating construction, wherein a steel strand is obliquely pulled, and a steering support applies a downward force to a midspan region to counteract the influence of upward buoyancy; the prestressed tensioning device consisting of the permanent anchor and the two finished anchorage devices is arranged, so that the steel strand can be conveniently and rapidly tensioned, and the steel strand is very firm after being anchored; the corresponding tensioning device is convenient and quick, and can be quickly disassembled after tensioning is finished; the tensioning structure and the method have the advantages of short construction period and quick anti-floating effect, all construction operations are carried out on the waterproof board surface, the construction is simple and convenient, the waterproof board does not need to be drilled through, the construction is not influenced by water pressure, the existing waterproof layer cannot be damaged, large-scale construction mechanical equipment is not needed, the existing basement clearance meets the construction requirements, and the tensioning structure and the method are suitable for large-scale popularization and use.)

1. The utility model provides a prestressing force stretch-draw structure for anti construction of floating, its includes ground base plate (1) and pile foundation (2), and ground base plate (1) is including pouring shaping and interconnect stride middle district (11) and support district (12), support district (12) bottom fixed connection pile foundation (2), its characterized in that: also comprises a prestress tension device (3), two steering supports (4), two strands of steel strands (5) and two self-locking anchoring devices (6),

the two steering supports (4) are respectively fixed on the surface of the middle spanning area (11) and are positioned between the two support areas (12);

the prestress tensioning device (3) is arranged between the two steering supports (4) and comprises a permanent anchor (31) and two finished product anchors (32), and holes for single steel wires of the steel strands (5) to pass through are formed in the permanent anchor (31) and the finished product anchors (32);

the two self-locking anchoring devices (6) respectively extend into the support area (12) in an inclined and downward manner and are anchored in a self-locking manner;

one end of each of the two steel strands (5) inclines downwards and is fixed with the self-locking anchoring device (6), the other end of each of the two steel strands penetrates through a finished product anchor (32), a permanent anchor (31) and the other finished product anchor (32) relatively and then is anchored with the finished product anchor (32) close to the tail end, the two steel strands (5) are anchored with the permanent anchor (31), and the middle parts of the two steel strands (5) are abutted to the two steering support seats (4) respectively.

2. The prestressed tension structure for anti-floating construction as claimed in claim 1, wherein: each strand of steel strand (5) comprises two or more single steel wires.

3. The prestressed tension structure for anti-floating construction as claimed in claim 2, wherein: a plurality of holes for steel wires to pass through are uniformly distributed on the permanent anchor (31) and the finished product anchor (32) in an annular mode, and the adjacent holes on the permanent anchor (31) and the finished product anchor (32) are penetrated by different strands of steel wires.

4. The prestressed tension structure for anti-floating construction as claimed in claim 2, wherein: drilling holes are formed between the middle crossing area (11) and the support area (12) along the downward inclined direction of the steel strand (5), expanded holes are formed in the bottoms of the drilling holes, the steel strand (5) penetrates through the drilling holes, and the end part of the steel strand and the expanded holes are anchored through the self-locking anchoring device (6).

5. The prestressed tension structure for anti-floating construction as claimed in claim 4, wherein: the self-locking anchoring device (6) comprises a self-locking anchoring rod (61) and a switching anchor joint (62), the self-locking anchoring rod (61) extends into the drill hole and forms self-locking with the enlarged hole, and the end part of the self-locking anchoring rod (61) is fixedly connected with the steel strand (5) through the switching anchor joint (62).

6. The prestressed tension structure for anti-floating construction as claimed in claim 1, wherein: the steering support (4) comprises a bearing seat (41) and a second anchor rod (42), the surface of the bearing seat (41) is an arc-shaped surface, the bottom of the bearing seat is fixed on the middle crossing area (11) through the second anchor rod (42), and the steel strand (5) is abutted to the arc-shaped surface of the bearing seat (41).

7. The prestressed tension structure for anti-floating construction as claimed in claim 1, wherein: the anti-floating support is applied to basement foundation anti-floating, four adjacent support areas (12) of the basement foundation are selected, and a prestress tensioning device (3), two steering supports (4), two strands of steel strands (5) and two self-locking anchoring devices (6) are arranged between the adjacent and opposite support areas (12) respectively.

8. The prestressed tension structure for anti-floating construction as claimed in claim 1, wherein: the steel wire tensioning device is characterized by further comprising a tensioning device (7), wherein the tensioning device (7) comprises two movable plates (71) and two jacks (72), grooves for single steel wires to penetrate through are formed in the movable plates (71), the movable plates (71) are arranged between the finished product anchorage devices (32) and the permanent anchors (31) and abut against the finished product anchorage devices (32), and the two jacks (72) are arranged between the two movable plates (71) and drive the two movable plates to move relatively.

9. The prestressed tension structure for anti-floating construction as claimed in claim 1, wherein: the anti-seepage assembly (8) of making level still includes, anti-seepage assembly (8) of making level includes anti-seepage concrete layer (81), reinforcing bar net piece (82) and first stock (83), and anti-seepage concrete layer (81) set up in basement floor (1) surface and submerge prestressing force tensioning equipment (3) and turn to support (4), and reinforcing bar net piece (82) are laid in anti-seepage concrete layer (81) and are anchored with basement floor (1) through first stock (83).

10. A prestress tension method for anti-floating construction is characterized in that: comprises the following steps of (a) carrying out,

s1, identifying the mounting position: finding out the position of the support area (12) according to an engineering drawing, connecting lines by taking the centers of the four support areas (12) as vertexes to form a quadrangle, and marking the middle point of the side line or the middle point of the diagonal line of the quadrangle on the ground floor board (1);

s2, mounting a steering support (4): symmetrically installing steering supports (4) on two sides of the middle point of the quadrilateral edge or the middle point of the diagonal line obtained in the step S1;

s3, punching and reaming: from the midspan region (11), drilling downwards towards the support region (12) in an inclined mode until the support region (12), and then reaming the bottom of the obtained drilled hole;

the execution sequence of the steps S2 and S3 is not sequential;

s4, installing a self-locking anchoring device (6): extending the self-locking anchoring device (6) into the drill hole, self-locking with the bottom reaming hole and fixing with the steel strand (5);

s5, prestress tension: the free ends of the two steel strands (5) penetrate through a finished product anchor (32), a permanent anchor (31) and another finished product anchor (32) and then are anchored with the finished product anchor (32) close to the tail end, then the two finished product anchors (32) are driven to move relatively, the two steel strands (5) are tensioned, and finally the two steel strands (5) are respectively anchored with the permanent anchor (31);

s6, leveling: and paving concrete on the foundation (1) so that the steering support (4) and the prestress tension device (3) are submerged by the concrete.

Technical Field

The invention relates to the technical field of anti-floating, in particular to a prestress tensioning structure and method for anti-floating construction.

Background

With the rapid development of social economy, new technologies and new materials are widely applied to building engineering projects, the more deep the basement of a newly built building is built, the more deep the basement is built, the deep excavated basement cannot be influenced by underground water level, and particularly, the basement bottom plate is easy to deform, crack, seep water and other diseases under the direct action of high-pressure underground water, so that the safety and normal use of the structure are influenced.

For the above-mentioned diseases, the conventional methods of thickening the bottom plate, pressing weight to resist floating, supplementing an anti-floating anchor rod behind a waterproof plate to resist floating, draining and reducing pressure are generally adopted, but the conventional method is adopted to solve the above-mentioned basement bottom plate anti-floating diseases and can also produce the following problems: 1. thickening the bottom plate and resisting floating by weight: the increased thickness of the bottom plate can greatly reduce the clear height of the basement, so that the use is influenced; 2. and (3) supplementing an anti-floating anchor rod behind the waterproof plate for anti-floating: the existing basement structure is formed, pressure underground water can gush out when a hole is formed in a bottom plate, silt below a foundation can be brought out along with the pressure underground water, the bottom of the foundation can be hollowed out seriously, the bearing capacity of the existing structural foundation is influenced, the structural potential safety hazard is generated, and the existing waterproof plate can be prevented from being damaged by anchor rod drilling and cannot be recovered; 3. draining and reducing pressure: the anti-floating problem cannot be fundamentally solved, the drainage ditch and the drainage facility need to be regularly enclosed, the operation cost is high, and the method is suitable for the soil layer with the upper layer of stagnant water and low water permeability, wherein the underground water is the soil layer.

Disclosure of Invention

In view of the above, the present invention provides a prestressed tension structure and method for anti-floating construction, which can enhance the anti-floating strength of basement foundation without affecting the use space of basement and damaging the foundation.

The technical scheme of the invention is realized as follows:

on one hand, the invention provides a prestressed tensioning structure for anti-floating construction, which comprises a foundation slab and a pile foundation, wherein the foundation slab comprises a mid-span region and a support region which are formed by casting and connected with each other, the bottom of the support region is fixedly connected with the pile foundation, the prestressed tensioning structure also comprises a prestressed tensioning device, two steering supports, two steel strands and two self-locking anchoring devices, wherein,

the two steering supports are respectively fixed on the surface of the middle spanning area and are positioned between the two support areas;

the prestress tensioning device is arranged between the two steering supports and comprises a permanent anchor and two finished anchorage devices, and the permanent anchor and the finished anchorage devices are provided with holes for single steel wires of the steel strands to pass through;

the two self-locking anchoring devices respectively extend into the support area in an inclined and downward manner and are anchored in a self-locking manner;

one end of each of the two strands of steel strands inclines downwards and is fixed with the self-locking anchoring device, the other end of each of the two strands of steel strands penetrates through a finished product anchorage device, a permanent anchor and the other finished product anchorage device respectively and is anchored with the finished product anchorage device close to the tail end, the two strands of steel strands are anchored with the permanent anchors respectively, and the middle parts of the two strands of steel strands are propped against the two steering support seats respectively.

On the basis of the technical scheme, preferably, each strand of steel strand comprises two or more single steel wires.

Preferably, the steel wires are threaded through the holes in the anchor and the finished anchor, and the steel wires are threaded through the holes in the anchor and the finished anchor.

Preferably, a drill hole is formed between the middle crossing area and the support area along the direction in which the steel strand inclines downwards, an enlarged hole is formed in the bottom of the drill hole, the steel strand penetrates through the drill hole, and the end part of the steel strand and the enlarged hole are anchored through a self-locking anchoring device.

Further preferably, the self-locking anchoring device comprises a self-locking anchoring rod and a conversion anchor joint, the self-locking anchoring rod extends into the drilled hole and forms self-locking with the enlarged hole, and the end part of the self-locking anchoring rod is fixedly connected with the steel strand through the conversion anchor joint.

On the basis of the technical scheme, preferably, the steering support comprises a bearing seat and a second anchor rod, the surface of the bearing seat is an arc-shaped surface, the bottom of the bearing seat is fixed on the middle span area through the second anchor rod, and the steel strand is abutted to the arc-shaped surface of the bearing seat.

On the basis of the technical scheme, preferably, the anti-floating support is applied to basement foundation anti-floating, four adjacent support areas of the basement foundation are selected, and a prestress tensioning device, two steering supports, two strands of steel strands and two self-locking anchoring devices are arranged between the adjacent and opposite support areas respectively.

On the basis of the technical scheme, the steel wire tensioning device preferably further comprises a tensioning device, the tensioning device comprises two movable plates and two jacks, grooves for single steel wires to penetrate through are formed in the movable plates, the movable plates are arranged between the finished product anchorage device and the permanent anchors and abut against the finished product anchorage device, and the two jacks are arranged between the two movable plates and drive the two movable plates to move relatively.

On the basis of the technical scheme, the anti-seepage leveling assembly preferably further comprises an anti-seepage leveling assembly, wherein the anti-seepage leveling assembly comprises an anti-seepage concrete layer, a steel bar net piece and a first anchor rod, the anti-seepage concrete layer is arranged on the surface of the ground floor slab and submerges the prestress tensioning device and the steering support, and the steel bar net piece is laid in the anti-seepage concrete layer and anchored with the ground floor slab through the first anchor rod.

In a second aspect, the present invention provides a prestressed tension method for anti-floating construction, comprising the steps of,

s1, identifying the mounting position: finding out the positions of the support areas according to an engineering drawing, connecting lines by taking the centers of the four support areas as vertexes to form a quadrangle, and marking the middle points of side lines or the middle points of diagonals of the quadrangle on the ground floor slab;

s2, mounting a steering support: symmetrically installing steering supports on two sides of the middle point of the quadrilateral sideline or the middle point of the diagonal line obtained in the step S1;

s3, punching and reaming: from the midspan region, obliquely drilling downwards towards the support region until reaching the support region, and then reaming the bottom of the obtained drilled hole;

the execution sequence of the steps S2 and S3 is not sequential;

s4, installing a self-locking anchoring device: extending the self-locking anchoring device into the drill hole, self-locking the self-locking anchoring device with the bottom reaming hole and fixing the self-locking anchoring device with the steel strand;

s5, prestress tension: the free ends of the two strands of steel strands penetrate through a finished anchorage device, a permanent anchor and another finished anchorage device and then are anchored with the finished anchorage device close to the tail end, then the two finished anchorage devices are driven to move relatively, the two strands of steel strands are tensioned, and finally the two strands of steel strands are respectively anchored with the permanent anchor;

s6, leveling: and paving concrete on the foundation, so that the concrete submerges the steering support and the prestress tension device.

Compared with the prior art, the prestress tensioning structure and method for anti-floating construction have the following beneficial effects:

(1) a downward force is applied to the midspan area through the steering support by obliquely pulling the steel strand to counteract the influence of the upward buoyancy;

(2) the prestressed tensioning device consisting of the permanent anchor and the two finished anchorage devices is arranged, so that the steel strand can be conveniently and rapidly tensioned, and the steel strand is very firm after being anchored;

(3) the corresponding tensioning device is convenient and quick, and can be quickly disassembled after tensioning is finished;

(4) the tensioning structure and the method have the advantages of short construction period and quick anti-floating effect, all construction operations are carried out on the waterproof board surface, the construction is simple and convenient, the waterproof board does not need to be drilled through, the construction is not influenced by water pressure, the existing waterproof layer cannot be damaged, large-scale construction mechanical equipment is not needed, the existing basement clearance meets the construction requirements, and the tensioning structure and the method are suitable for large-scale popularization and use.

Drawings

In order to more clearly illustrate the 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 described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.

FIG. 1 is a plan view of the prestressed tension structure of the present invention applied to a basement;

FIG. 2 is a schematic cross-sectional structural view of a pre-stressed tension structure according to an embodiment of the present invention;

FIG. 3 is an enlarged view of the oval area of FIG. 2;

FIG. 4 is an enlarged view of the circled area in FIG. 2;

fig. 5 is a schematic view showing the operation of the prestress tensioner of the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be obtained by a person skilled in the art without any inventive step based on the embodiments of the present invention, are within the scope of the present invention.

As shown in fig. 1 to 5, the prestressed tensioning structure for anti-floating construction of the present invention includes a foundation slab 1, a pile foundation 2, a prestressed tensioning device 3, two steering supports 4, two strands of steel strands 5, a self-locking anchoring device 6, a tensioning device 7, and a leveling and anti-permeability assembly 8.

The ground base plate 1 is formed by pouring reinforced concrete in the prior art. The ground floor slab 1 comprises a midspan region 11 and a support region 12 which are integrally cast and connected with each other, the support region 12 is a main bearing region of a building, a bearing platform region is generally arranged at the bottom of the building, the bottom of the building is fixedly connected with a pile foundation 2, the casting thickness of the building is generally thicker, the area of the building is relatively smaller, and therefore the floating resistance of the building is stronger; the midspan area 11 is a pouring area connected between the support areas 12, is relatively weak in thickness and large in area, so that the anti-floating capacity is poor, and the fracture is easy to occur under the buoyancy action of underground water.

The main design idea of the invention is as follows: the buoyancy borne by the midspan region 11 is conducted to the support region 12 through the stayed-steel wires, thereby providing anti-buoyancy to the midspan region 11 and preventing the midspan region from cracking.

Specifically, two steering seats 4 are respectively fixed on the surface of the midspan region 11 and located between the two seat regions 12. The steering support 4 is arranged at the steering position of the steel strand 5 and supports the steel strand, and specifically comprises a bearing seat 41 and a second anchor rod 42, wherein the surface of the bearing seat 41 is an arc-shaped surface, the bottom of the bearing seat is fixed on the middle crossing area 11 through the second anchor rod 42, and the steel strand 5 is abutted to the arc-shaped surface of the bearing seat 41. The arc-shaped surface is arranged to prevent a single steel wire from being in frictional fracture with the steel wire, and the single steel wire are in line contact with each other to uniformly disperse the force of the steel strand 5.

And the prestress tensioning device 3 is arranged between the two steering supports 4 and used for tensioning and fixing the two strands of steel strands 5. The pre-stressed tension device 3 comprises a permanent anchor 31 and two finished anchorage devices 32, wherein the permanent anchor 31 and the finished anchorage devices 32 are provided with holes for single steel wires of the steel strand 5 to pass through.

And the two self-locking anchoring devices 6 respectively extend into the support area 12 in an inclined and downward manner and are anchored in a self-locking manner. Specifically, a drill hole is formed between the middle crossing area 11 and the support area 12 along the downward inclined direction of the steel strand 5, an enlarged hole is formed in the bottom of the drill hole, the steel strand 5 penetrates through the drill hole, and the end part of the steel strand and the enlarged hole are anchored through the self-locking anchoring device 6. The self-locking anchoring device 6 comprises a self-locking anchoring rod 61 and a conversion anchor joint 62, the self-locking anchoring rod 61 extends into the drill hole and forms self-locking with the enlarged hole, and the end part of the self-locking anchoring rod 61 is fixedly connected with the steel strand 5 through the conversion anchor joint 62. The self-locking anchoring device 6 can adopt the existing self-locking technology and is not limited to the self-locking anchor rod 61 provided by the embodiment.

One end of each of the two steel strands 5 is inclined downwards and fixed with the self-locking anchoring device 6, the other end of each of the two steel strands 5 penetrates through a finished product anchorage device 32, a permanent anchor 31 and another finished product anchorage device 32 relatively and then is anchored with the finished product anchorage device 32 close to the tail end, the two steel strands 5 are anchored with the permanent anchor 31 respectively, and the middle parts of the two steel strands 5 are abutted to the two steering supports 4 respectively. Under the supporting action of the steering support 4, the steel strand 5 applies a downward force to the steering support 4 and conducts the downward force to the midspan region 11, so that the anti-floating capacity of the steel strand is improved.

As a preferred embodiment, each strand of steel strand 5 comprises two or more steel wires, and the steel wires have higher tensile strength and are convenient to anchor.

In order to improve the stress balance between the permanent anchor 31 and the finished anchor 32, as a preferred embodiment, a plurality of holes for steel wires to pass through are uniformly distributed on the permanent anchor 31 and the finished anchor 32 in a ring shape, and adjacent holes on the permanent anchor 31 and the finished anchor 32 are penetrated by steel wires of different strands.

The invention further provides a tensioning device 7 for tensioning, wherein the tensioning device 7 comprises two movable plates 71 and two jacks 72, the movable plates 71 are provided with grooves for single steel wires to pass through, the movable plates 71 are arranged between the finished product anchorage device 32 and the permanent anchors 31 and are abutted against the finished product anchorage device 32, and the two jacks 72 are arranged between the two movable plates 71 and drive the two movable plates 71 to move relatively. The two jacks 72 drive the two movable plates 71 to move relatively, so that the two finished anchorage devices 32 are separated, the steel strand 5 anchored with the finished anchorage devices 32 is tensioned, then the steel strand 5 is anchored with the permanent anchors 31, tensioning and anchoring can be completed, and the tensioning device 7 can be detached after tensioning is completed.

Aiming at the application scene of basement foundation anti-floating, four adjacent support areas 12 of the basement foundation are selected, a steering support 4 is arranged between the adjacent and opposite support areas 12, and a prestress tensioning device 3, two steering supports 4 and two strands of steel strands 5 are respectively arranged between the adjacent and opposite support areas 12. Therefore, the steering support 4 is distributed at multiple points on the midspan area 11, and can play a better anti-floating role.

The prestress tension method for anti-floating construction of the present embodiment is described below, including the steps of,

s1, identifying the mounting position: according to engineering drawings, the positions of the support areas 12 are found out, a quadrilateral is formed by connecting lines by taking the centers of the four support areas 12 as vertexes, and the midpoints of side lines or the midpoints of diagonals of the quadrilateral are marked on the ground base plate 1. Generally speaking, the prestress tension device 3 is arranged near the position of the middle point of the side line or the middle point of the diagonal line of the quadrangle.

S2, mounting the steering bracket 4: the steering brackets 4 are symmetrically arranged on both sides of the middle point of the quadrilateral edge or the middle point of the diagonal line obtained in the step S1. Specifically, the force bearing seat 41 is fixed on the middle crossing area 11 through the second anchor rod 42, the depth of the second anchor rod 42 cannot exceed the thickness of the middle crossing area 11, otherwise, the problem of water leakage through the hole occurs.

S3, punching and reaming: starting from the midspan region 11, the hole is drilled obliquely downwards into the seat region 12 up to the seat region 12 and then the hole is reamed in the bottom of the resulting borehole. Drilling and reaming are well established techniques and will not be described in detail herein.

The execution sequence of the steps S2 and S3 is not sequential, and may be performed synchronously or sequentially.

S4, anchoring the steel strand 5: and (3) extending the self-locking anchoring device 6 into the drill hole, self-locking with the bottom reaming hole and fixing with the steel strand 5. The above self-locking anchoring technology can adopt the prior art, and is not described in detail herein.

S5, prestress tension: and tensioning the free end of the steel strand 5 through a steering support 4, and anchoring the steel strand with the prestress tensioning device 3. Specifically, as shown in fig. 5, a steel wire on one strand of steel strand 5 is first passed through a finished anchor 32, a permanent anchor 31 and another finished anchor 32, and then anchored with the finished anchor 32 near the end, then the two finished anchors 32 are driven to move relatively, two strands of steel strand 5 are tensioned, and finally two strands of steel strand 5 are anchored with the permanent anchor 31 respectively. Specifically, in the process of tensioning two strands of steel strands 5, the two jacks 72 drive the two movable plates 71 to move relatively, so that the two finished anchorage devices 32 are separated, the steel strands 5 anchored with the finished anchorage devices 32 are tensioned, then the steel strands 5 are anchored with the permanent anchors 31, and then tensioning and anchoring can be completed, and the tensioning device 7 can be detached after tensioning is completed. In this way, the two strands 5 can form an anchor.

S6, leveling: concrete is laid on the foundation 1 so that the concrete submerges the steering support 4 and the prestress tensioning device 3. Specifically, an impervious concrete layer 81 may be laid on the foundation 1, and in the process, a steel mesh 82 is implanted and anchored with the ground base plate 1 by a first anchor rod 83.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like that fall within the spirit and principle of the present invention are intended to be included therein.