CN114382085B

CN114382085B - A kind of retaining pile and its construction method and steel cage structure manufacturing method

Info

Publication number: CN114382085B
Application number: CN202111495440.5A
Authority: CN
Inventors: 应晓阳; 冯维维; 杨萤; 詹晓波; 王俊; 郭兆明; 吕小欣; 邵友法; 徐海泳; 汪悦
Original assignee: Zhejiang Dadi Survey And Design Co ltd
Current assignee: Zhejiang Dadi Survey And Design Co ltd
Priority date: 2021-12-08
Filing date: 2021-12-08
Publication date: 2024-12-03
Anticipated expiration: 2041-12-08
Also published as: CN114382085A

Abstract

The present application discloses a retaining pile and a construction method thereof and a method for manufacturing a steel cage structure. Belonging to the field of construction engineering technology, the retaining pile and the construction method thereof can apply the steel strand prestressing technology to the retaining pile, and recycle the steel strands in the non-stressed direction, saving the amount of steel; at the same time, the prestressing technology is used to improve the rigidity of the retaining pile, improve the overall stability of the soil, and reduce the deformation and settlement of the surrounding environment of the foundation pit, and the structure is simple, easy to use, and highly reliable. It includes a steel cage structure, wherein the steel cage structure includes a steel cage skeleton and a plurality of U-shaped tubes arranged on the steel cage skeleton, and steel strands passing through the U-shaped tubes; the steel cage skeleton includes longitudinal bars and stirrups, and the U-shaped tubes are arranged at equal intervals along the inner side of the steel cage skeleton, and the steel strands passing through the U-shaped tubes are carriers for applying prestress.

Description

Guard pile, construction method thereof and manufacturing method of reinforcement cage structure

Technical Field

The invention relates to the technical field of constructional engineering, in particular to a fender pile and a construction method thereof and a manufacturing method of a reinforcement cage structure.

Background

When the foundation pit is excavated in the construction of the building engineering, the foundation pit needs to be temporarily supported so as to ensure the safety of the surrounding environment of the foundation pit. When the excavation depth of the foundation pit is large, the supporting mode is usually a mode of adding supporting by using guard piles, wherein the guard piles mainly comprise bored piles, SMW construction method piles, underground continuous walls and the like. When adopting common drilling bored concrete pile, if the foundation ditch excavation degree of depth is darker, then the atress of fender post is great, in order to guarantee safety, the reinforcing bar that needs to dispose is more, and the steel consumption is big. When the foundation pit is excavated, the guard piles deform under the action of soil pressure, the periphery of the foundation pit deforms along with the deformation of the guard piles, and the problems of ground cracking, sedimentation and the like can occur when the foundation pit is seriously excavated.

The steel strand is often used in prestress structural members due to the characteristics of high strength, portability and the like, and is widely applied to the fields of large-span structures, bridges and the like. Pretensioning prestressing is also commonly used in prefabricated components, such as prefabricated panels, prefabricated piles, etc. In underground engineering, steel strands are mainly used in slope engineering and precast piles, and due to complex technology, the steel strands are rarely used in fender pile engineering.

Therefore, there is a need to develop a fender post, a construction method thereof and a reinforcement cage structure manufacturing method to solve the problems in the prior art.

Disclosure of Invention

The invention aims to provide a fender post, a construction method thereof and a reinforcement cage structure manufacturing method, so as to solve the problems in the background art. The invention mainly aims to apply the steel strand prestress technology to the fender post and save the steel consumption. Meanwhile, the rigidity of the fender post is improved by utilizing a prestressing technology, the overall stability of soil is improved, and the deformation and settlement of the periphery of the foundation pit are reduced.

In order to achieve the above purpose, the present invention provides the following technical solutions:

The fender post comprises a reinforcement cage structure, wherein the reinforcement cage structure comprises a reinforcement cage framework, a plurality of U-shaped pipes and steel strands penetrating through the U-shaped pipes, the plurality of U-shaped pipes are arranged on the reinforcement cage framework, the reinforcement cage framework comprises longitudinal ribs and stirrups, the U-shaped pipes are arranged at equal intervals along the inner side of the reinforcement cage framework, and the steel strands penetrating through the U-shaped pipes are carriers for applying prestress.

As a further scheme of the invention, the U-shaped pipe is fixed on the inner side of the reinforcement cage framework and bent into a U shape at a certain distance from the bottom of the reinforcement cage framework.

As a further scheme of the invention, the plurality of U-shaped pipes are arranged at equal intervals in the horizontal direction, are staggered close to the bottom end of the reinforcement cage framework in the vertical direction, and are fixed on the reinforcement cage framework.

According to the foundation pit supporting structure, the crown beam is arranged at the top end of the reinforcement cage structure, the crown beam and the reinforcement cage structures are connected together through concrete pouring to form the foundation pit supporting structure, steel strands of the reinforcement cage structure penetrate through the crown beam and then stretch-draw anchor, and then grouting is carried out into the U-shaped pipe to be filled.

A manufacturing method of a reinforcement cage structure of a fender post of the fender post comprises the following steps:

s1, uniformly distributing a plurality of longitudinal bars and stirrups at certain intervals and assembling the longitudinal bars and the stirrups into a reinforcement cage framework;

s2, threading a plurality of steel strands into the U-shaped pipe;

S3, uniformly fixing straight line sections of the U-shaped pipe on the reinforcement cage framework according to the interval;

s4, fixing the U-shaped part of the U-shaped pipe near the bottom of the reinforcement cage framework, and staggering;

s5, integrally manufacturing the reinforcement cage structure.

A construction method of a fender pile, comprising:

S1, assembling a reinforcement cage structure by a reinforcement cage framework, a U-shaped pipe and a steel strand penetrating the U-shaped pipe;

s2, lowering the reinforcement cage structure into the pile hole, filling clear water into the U-shaped pipe, and blocking the top end of the U-shaped pipe, wherein S3, pile body concrete is poured, and the end heads of the steel strands extend out of the concrete surface;

S4, recycling the steel strands in the non-stressed direction;

And S5, tensioning and anchoring the steel stranded wires after the concrete strength of the pile body and the crown beam is met, grouting and filling the U-shaped pipe, and putting the bonded prestressed guard pile into engineering by a post-tensioning method.

The invention further adopts the scheme that the reinforcement cage structure in the step S2 is lowered into the pile hole, clean water is filled into the U-shaped pipe, the top end of the U-shaped pipe is blocked, protection measures are taken, and concrete is poured into the pile body.

Compared with the prior art, the invention has the beneficial effects that the steel strand prestress technology is used for the guard pile, the steel strands with three times of strength and one third of weight in the stress direction can be replaced, and the steel strands with no stress direction can be recovered to save the steel consumption. Meanwhile, a new method for realizing the prestress technology in the fender post is provided, the construction process is simple and convenient, the rigidity of the fender post is improved, the overall stability of soil is improved, and the deformation of the periphery of a foundation pit is reduced.

Other features and advantages of the present invention will be disclosed in the following detailed description of the invention and the accompanying drawings.

Drawings

FIG. 1 is a schematic view of the overall construction of a fender post according to an embodiment of the invention;

FIG. 2 is a schematic top view of a fender post in an embodiment of the invention;

FIG. 3 is a schematic cross-sectional view of a U-tube in accordance with an embodiment of the present invention;

FIG. 4 is a schematic illustration of one position of a pile top connection in an embodiment of the present invention;

fig. 5 is a schematic flow chart of a construction method of a prestressed fender pile in an embodiment of the present invention.

In the figure, the reference numerals are a reinforcement cage structure 1, a reinforcement cage framework 11, stirrups 111, longitudinal ribs 112, U-shaped pipes 12, steel strands 13, pile holes 2, a stress area 3, a pressure-bearing steel plate 4 and a crown beam 5.

Detailed Description

The following description of the embodiments of the present invention will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present invention, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.

In the embodiment of the invention, the fender post is shown in fig. 1-4, and comprises a reinforcement cage structure 1, wherein the reinforcement cage structure 1 comprises a reinforcement cage framework 11, a plurality of U-shaped pipes 12 arranged on the reinforcement cage framework 11 and steel strands 13 penetrating through the U-shaped pipes 12, the reinforcement cage framework 11 comprises longitudinal ribs 112 and stirrups 111, the U-shaped pipes 12 are arranged at equal intervals along the inner side of the reinforcement cage framework 11, and the steel strands 13 penetrating through the U-shaped pipes 12 are carriers for applying prestress.

Wherein, because the design value of the tensile strength of the HRB400 steel bar is 360MPa, the design value of the tensile strength of the common steel strand 13 is 1320MPa, and the design value of the tensile strength of the steel strand 13 is about 3.67 times of the design value of the tensile strength of the HRB400 steel bar. Under the condition of the same strength, the steel consumption of the steel strand 13 is less than one third of that of the HRB400 steel bar. Compared with the traditional mode of adopting the steel bars, in the embodiment of the invention, the steel strands 13 in the stress direction are used for replacing the steel bars, and the steel strands in the non-stress direction can be pulled out and put into the next pile for use, so that the steel consumption can be saved by more than one half.

The fender post that this embodiment provided, pile head are above ground, and convenient stretch-draw adopts prestressing force steel strand wires 13 as the main muscle, and the intensity of steel strand wires 13 can fully play a role, improves pile body quality, reduces the stake crack, and increases pile body rigidity, reduces foundation ditch peripheral deformation. During construction, the steel reinforcement cage structure 1 is free of requirements on the placement direction, can be placed at will according to the convenience of construction, and after the concrete pouring of the pile body is completed and certain strength exists, the steel strands in the unstressed direction are recycled and put into the next pile for use, so that the steel reinforcement cage structure is green and environment-friendly.

In this embodiment, referring to fig. 1-3, the U-shaped tube 12 is fixed on the inner side of the reinforcement cage 11, and is bent into a U shape at a distance from the bottom of the reinforcement cage 11. The U-shaped tube 12 extends from one side of the top of the cage 11 to the bottom, curves into a U-shape at a distance (e.g., about 2 m) from the bottom of the cage 11 and returns to the top of the cage 11 along the other side of the cage 11. Because the U-shaped pipe 12 does not need to be provided with an anchorage device at the bottom, the problems that grouting is difficult and the grouting quality is unreliable under the condition of closed bottom end of the pipe, and soil impurities falling into the pipe are difficult to remove due to closed bottom end of the pipe, so that the grouting quality is affected are avoided.

In this embodiment, referring to fig. 1-3, a plurality of U-shaped pipes 12 are arranged at equal intervals in a horizontal direction, are staggered near the bottom end of the reinforcement cage 11 in a vertical direction, and are fixed on the reinforcement cage 11. The plurality of U-shaped pipes 12 are fixed on the reinforcement cage framework 11 in a staggered arrangement mode in the horizontal direction at equal intervals and in the vertical direction near the lower end of the reinforcement cage framework 11. In the vertical direction, for example, the first U-shaped pipe 12 passes from the top of the pile to near the bottom of the pile and then turns back, and the second U-shaped pipe 12 passes to a position about 1 meter above the bottom of the first U-shaped pipe 12 and turns back. The U-shaped tubes 12 are equally spaced in the planar direction. By orderly staggering the U-shaped pipes 12 in the horizontal direction and the vertical direction, the U-shaped pipes do not interfere with each other and exert the prestress effect respectively.

In this embodiment, referring to fig. 1-4, a crown beam 5 is provided at the top end of a reinforcement cage structure 1, and the crown beam 5 and a plurality of reinforcement cage structures 1 are connected together by concrete pouring to construct a foundation pit supporting structure, wherein steel strands 13 of the reinforcement cage structure 1 pass through the crown beam 5 and then are tensioned and anchored, and then grouting is performed into a U-shaped pipe 12. After the pouring of the crown beam 5 at the pile top of the guard pile is completed and certain strength is met, the steel stranded wires 13 are tensioned and anchored, and cement paste is filled into the U-shaped pipe 12. The symmetrical stretching mode can prevent the concrete from generating overstress, prevent the reinforcement cage from twisting, lateral bending and the like. The post-tensioning method is adopted to apply the prestress without pedestal equipment, so that the flexibility is high. The construction method integrates the prestressed tendons and the concrete structure, and improves the anchoring reliability and durability of the prestressed tendons.

S1, uniformly distributing a plurality of longitudinal ribs 112 and stirrups 111 at certain intervals and assembling the longitudinal ribs and the stirrups into a reinforcement cage framework 11, S2, penetrating a plurality of steel strands 13 into a U-shaped pipe 12;

S3, uniformly fixing the straight line section of the U-shaped pipe 12 on the reinforcement cage framework 11 according to the interval;

s4, fixing the U-shaped part of the U-shaped pipe 12 near the bottom of the reinforcement cage framework 11, and staggering;

S5, integrally manufacturing the reinforcement cage structure 1.

A method of construction of a fender pile, as shown in fig. 5, comprising:

S1, assembling a reinforcement cage structure 1 by a reinforcement cage framework 11, a U-shaped pipe 12 and a steel strand 13 penetrating into the U-shaped pipe 12;

s2, the reinforcement cage structure 1 is placed in a pile hole, clear water is filled into the U-shaped pipe 12, and the top end of the U-shaped pipe 12 is blocked;

s3, pouring pile body concrete, wherein the end heads of the steel strands 13 extend out of the concrete surface;

S4, recycling the steel stranded wires 13 in the non-stressed direction;

S5, tensioning and anchoring the steel stranded wires after the concrete strength of the pile body and the crown beam 5 is satisfied, and grouting and filling the U-shaped pipe 12;

S6, the post-tensioning method is used for engineering with the bonded prestressed guard piles.

The construction method of the guard pile in the embodiment is that the stirrup 111, the longitudinal ribs 112, the U-shaped pipe 12 and the steel stranded wires 13 are assembled into the steel reinforcement cage structure 1, the matched steel stranded wires 13 are designed and pass through the U-shaped pipe 12, the steel stranded wires 13 pass through the steel reinforcement cage structure 1 of the U-shaped pipe 12 and are placed in the pile hole 2, concrete is poured into the pile hole 3, the crown beam 5 is poured into the pile top, the steel stranded wires 13 are stretched and anchored at the pile top after the concrete strength of the pile body and the crown beam 5 is met, cement paste is filled into the U-shaped pipe 12, and the guard pile is put into engineering use, so that the steel consumption of steel bars is reduced, the weight of the steel reinforcement cage structure 1 is lightened, the rigidity of the guard pile is increased, and the deformation of a foundation pit is reduced. And meanwhile, the steel stranded wires 13 of the non-stressed part are recovered and put into the next pile for use, so that economy is realized.

Referring to fig. 4 to 5, the reinforcement cage structure 1 is lowered to the pile hole 2, clean water is injected into the U-shaped pipe 12, and the top end of the U-shaped pipe 12 is blocked, so that concrete can be prevented from entering the U-shaped pipe 12 in the pile body concrete pouring process, and meanwhile the U-shaped pipe is protected from being damaged in the pile body concrete pouring process. And a pressure-bearing steel plate 4 for dispersing pressure is arranged between the pile body and the crown beam 5, so that the damage caused by stress concentration at the pile body and the crown beam is prevented. And then the steel strands which are not in the stress area 3 in the non-stress direction are recovered according to the stress requirement.

The invention provides a fender post, a construction method thereof and a manufacturing method of a reinforcement cage structure, which can use a steel strand prestress technology for the fender post, save steel consumption, and simultaneously utilize the prestress technology to improve the rigidity of the fender post, improve the overall stability of soil, reduce the deformation and settlement of the periphery of a foundation pit, and have the advantages of simple structure, convenient use and high reliability.

It will be evident to those skilled in the art that the invention is not limited to the details of the foregoing illustrative embodiments, and that the present invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. The present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. Any reference sign in a claim should not be construed as limiting the claim concerned.

Furthermore, it should be understood that although the present disclosure describes embodiments, not every embodiment is provided with a separate embodiment, and that this description is provided for clarity only, and that the disclosure is not limited to the embodiments described in detail below, and that the embodiments described in the examples may be combined as appropriate to form other embodiments that will be apparent to those skilled in the art.

Claims

1. A construction method for a retaining pile, characterized in that it comprises a steel cage structure, wherein the steel cage structure comprises a steel cage skeleton and a plurality of U-shaped tubes arranged on the steel cage skeleton, and steel strands passing through the U-shaped tubes; the steel cage skeleton comprises longitudinal bars and stirrups, the U-shaped tubes are arranged at equal intervals along the inner side of the steel cage skeleton, and the steel strands passing through the U-shaped tubes are carriers for applying prestress;

A cap beam is provided at the top of the steel cage structure, and the cap beam is connected with a plurality of steel cage structures by pouring concrete to form a foundation pit support structure, wherein the steel strands of the steel cage structure are tensioned and anchored after passing through the cap beam, and then grouting is filled into the U-shaped tube; the construction method of the retaining pile comprises:

S1: The steel cage structure is assembled by a steel cage frame, a U-shaped tube and steel strands inserted into the U-shaped tube;

S2: The steel cage structure is lowered into the pile hole, the U-shaped tube is filled with clean water, and the top of the U-shaped tube is sealed;

S3: pouring pile concrete, with the ends of the steel strands extending out of the concrete surface;

S4: Recover the steel strands in the non-stress direction;

S5: After the concrete strength of the pile body and cap beam meets the requirements, the steel strands are tensioned and anchored, and the U-shaped tube is filled with grouting;

S6: Post-tensioned bonded prestressed retaining piles are put into use in the project.

2. The construction method of retaining piles according to claim 1 is characterized in that the U-shaped tube is fixed on the inner side of the steel cage frame and is bent into a U shape at a certain distance from the bottom of the steel cage frame.

3. The construction method of retaining piles according to claim 1 or 2 is characterized in that a plurality of U-shaped tubes are arranged at equal intervals in the horizontal direction, are staggered in the vertical direction toward the bottom end of the steel cage frame, and are fixed on the steel cage frame.

4. The construction method of the retaining pile according to claim 1 is characterized in that the steel cage structure in S2 is lowered into the pile hole, the U-shaped tube is filled with clean water and the top of the U-shaped tube is sealed, protective measures are taken, and the pile body is then poured with concrete.

5. A method for manufacturing a steel cage structure of a retaining pile, characterized in that it comprises a steel cage structure, wherein the steel cage structure comprises a steel cage frame and a plurality of U-shaped tubes arranged on the steel cage frame, and steel strands passing through the U-shaped tubes; the steel cage frame comprises longitudinal bars and stirrups, the U-shaped tubes are arranged at equal intervals along the inner side of the steel cage frame, and the steel strands passing through the U-shaped tubes are carriers for applying prestress;

The production method includes:

S1: Several longitudinal bars and stirrups are evenly distributed at a certain interval and assembled into a steel cage skeleton;

S2: insert several steel strands into the U-shaped tube;

S3: The straight section of the U-shaped tube is fixed on the steel cage frame at uniform intervals;

S4: The U-shaped part of the U-shaped tube is fixed near the bottom of the steel cage frame and arranged staggered;

S5: The overall fabrication of the steel cage structure is completed.