WO2023024348A1

WO2023024348A1 - Recyclable prestressed support system and construction method

Info

Publication number: WO2023024348A1
Application number: PCT/CN2021/139584
Authority: WO
Inventors: 梁伟桥; 吴旭君; 龚超; 曹文昭; 于至海
Original assignee: 中冶建筑研究总院（深圳）有限公司
Priority date: 2021-08-26
Filing date: 2021-12-20
Publication date: 2023-03-02
Also published as: CN113529746A

Abstract

Disclosed in the embodiments of the present application are a recyclable prestressed support system and a construction method. The recyclable prestressed support system comprises two rows of enclosure structures, two crown beams, and a bridge-type prestressed supporting system. The two rows of enclosure structures are arranged on two sides of a foundation pit at intervals, each row of enclosure structures comprises a plurality of recyclable support piles that are sequentially engaged, and a first prestressed structure is provided in each recyclable support pile. The plurality of recyclable support piles of each row of enclosure structures are connected to one crown beam, and the first prestressed structure is provided in each crown beam. The bridge-type prestressed supporting system has two ends arranged on the respective crown beams and is connected to the two crown beams, the bridge-type prestressed supporting system is provided with a bearing face for bearing a soil body, and a second prestressed structure is provided in the bridge-type prestressed supporting system.

Description

Recyclable prestressed support system and construction method

This application claims the priority of the Chinese patent application with application number 202110986047.X submitted to the China Patent Office on August 26, 2021, and the entire content of the above application is incorporated by reference in this application.

technical field

The present application relates to the technical field of foundation pit engineering, for example, to a recyclable prestressed support system and a construction method.

Background technique

The support system of support pile + internal support is one of the most common and widely used support types in foundation pit engineering. Both the supporting piles and the inner support are made of concrete. Although it has strong applicability and can control the deformation of the foundation pit well, the concrete needs curing time and a long construction period. After the foundation pit project is completed, the support has to be removed, resulting in construction waste and waste of resources. In some municipal pipe gallery projects, it is often necessary to excavate a foundation pit with a certain width and a long longitudinal length, and the longitudinal construction needs to be divided into sections.

During the construction of the pipe gallery project, it is necessary to construct concrete support structures on both sides of the pipe gallery to achieve the support effect. The support components cannot be recovered after the construction is completed, and the support components are often passive supports. , its deformation is difficult to control, in order to ensure that it has a better support effect, the cross section of the support member is often designed to be larger, which further increases the cost that is difficult to recover. At the same time, during the construction of the foundation pit, the earthwork needs to be excavated and transported out of the site. After the construction of the pipe gallery, part of the earthwork needs to be transported back for backfilling. At the same time, the construction efficiency is reduced, and the construction cost and carbon emissions are increased.

Therefore, there is an urgent need for a recyclable prestressed support system and construction method to solve the above problems.

Contents of the invention

The embodiment of the present application discloses a recyclable prestressed support system, including: two rows of enclosure structures, the two rows of enclosure structures are arranged at intervals on both sides of the foundation pit, and each row of enclosure structures includes multiple The retrievable support piles engaged in sequence, each of the retrievable support piles is provided with a first prestressed structure; two crown beams, a plurality of the retrievable support piles of each row of the enclosure One of the two crown beams is connected to the guard pile, and each of the crown beams is provided with the first prestressed structure; a bridge-type prestressed support system, and the bridge-type prestressed support system The two ends of the system are respectively arranged on one of the two crown beams and connected with the two crown beams, and the bridge type prestressed support system is provided with a bearing surface for bearing soil, The bridge type prestressed support system is provided with a second prestressed structure.

The embodiment of the present application discloses a construction method of a recyclable prestressed support system, based on the aforementioned recyclable prestressed support system, including: S1, setting up enclosure structures on both sides of the foundation pit in the construction section ; S2. Fix and connect the crown beam on the inner side of the top of the two rows of enclosure structures; S3. Install bridge-type prestressed support system on the crown beam; The body is stacked on the bearing surface of the bridge prestressed support system, and the first prestressed structure in the enclosure structure and the second prestressed structure in the bridge prestressed support system are applied S5, after the construction of the underground structure in the foundation pit of the construction section is completed, backfill the soil (soil on the bearing surface of the prestressed support system) into the construction section; S6, release the surrounding The prestressing of the first prestressed structure in the protective structure and the second prestressed structure in the bridge prestressed support system, the bridge prestressed support system, the crown beam and part of the enclosure Protective structure; S7. Repeat steps S1-S6 in the next construction section until the construction of the entire construction section is completed.

Additional aspects and advantages of the application will be set forth in part in the description which follows, and in part will be learned by practice of the application.

Description of drawings

Fig. 1 is the structural representation during construction of the recyclable prestressed support system that the specific embodiment of the application provides;

Fig. 2 is a schematic structural view of a bridge-type prestressed support system and a second prestressed structure provided by a specific embodiment of the present application;

Fig. 3 is the front view of the bridge type prestressed support system, the second prestressed structure and the crown beam provided by the specific embodiment of the present application;

Fig. 4 is one of the internal partial structure schematic diagrams of the recyclable support pile and the crown beam provided by the specific embodiment of the application;

Fig. 5 is the second schematic diagram of the internal partial structure of the recyclable support pile and the crown beam provided by the specific embodiment of the present application;

Fig. 6 is a flow chart of the construction method of the recyclable prestressed support system provided by the specific embodiment of the present application.

reference sign

1. Recyclable support pile; 11. Recyclable steel pipe; 12. Plastic concrete;

2. The first prestressed structure; 21. The first anchorage; 22. The first steel strand;

3. Crown beam;

4. Bridge-type prestressed support system; 41. Bearing components; 411. Main girder of bridge deck; 4111. H-shaped steel; 4112. Connecting plate; 4113. Stiffener; 412. Diagonal support; 413. Supporting plate; beam; 42, high-strength steel rod; 43, displacement regulator;

5. The second prestressed structure; 51. The second anchor; 52. The second steel strand; 53. The support rod;

101, base plate; 102, pipe gallery; 103, soil mass.

Detailed ways

The technical solution of the present application will be described below in conjunction with the accompanying drawings and through specific implementation methods.

In the description of this application, unless otherwise clearly specified and limited, the terms "connected", "connected" and "fixed" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integrated ; It can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediary, and it can be the internal communication of two components or the interaction relationship between two components. Those of ordinary skill in the art can understand the specific meanings of the above terms in this application in specific situations.

In this application, unless otherwise expressly specified and limited, a first feature being "on" or "under" a second feature may include direct contact between the first and second features, and may also include the first and second features Not in direct contact but through another characteristic contact between them. Moreover, "above", "above" and "above" the first feature on the second feature include that the first feature is directly above and obliquely above the second feature, or simply means that the first feature is horizontally higher than the second feature. "Below", "beneath" and "under" the first feature to the second feature include that the first feature is directly below and obliquely below the second feature, or simply means that the first feature has a lower level than the second feature.

It will be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "Right", "Vertical", "Horizontal", "Top", "Bottom", "Inner", "Outer", "Clockwise", "Counterclockwise", "Axial", "Radial", " The orientation or positional relationship indicated by "circumferential direction" and so on is based on the orientation or positional relationship shown in the drawings, which is only for the convenience of describing the application and simplifying the description, rather than indicating or implying that the referred device or element must have a specific orientation, constructed and operated in a particular orientation and therefore should not be construed as limiting the application. In the description of the present application, unless otherwise specified, "plurality" means two or more. In addition, the terms "first" and "second" are only used to distinguish in description, and have no special meaning.

The following describes the recyclable prestressed support system and construction method of the embodiment of the present application with reference to FIGS. 1-6 .

FIG. 4 is a schematic view of the internal partial structure of the structure depicted in FIG. 1 under a front view.

FIG. 5 is a schematic diagram of the internal partial structure of the structure depicted in FIG. 1 in a top view.

As shown in FIGS. 1-5 , FIG. 1 discloses a recoverable prestressed support system, which includes two rows of enclosure structures, two crown beams 3 and a bridge-type prestressed support system 4 . Two rows of enclosure structures are arranged at intervals on both sides of the foundation pit, and each row of enclosure structures includes a plurality of retrievable support piles 1 that are sequentially engaged, and each retrievable support pile 1 is provided with a first prestressed structure 2. A crown beam 3 is connected to a plurality of recoverable support piles 1 of each row of enclosure structures, and a first prestressed structure 2 is arranged inside each crown beam 3 . The two ends of the bridge-type prestressed support system 4 are respectively arranged on a crown beam 3 and connected with the crown beam 3. The bridge-type prestressed support system 4 is provided with a bearing surface for bearing the soil 103. The bridge-type prestressed support system 4 is provided with a second prestressed structure 5 .

It is understandable that since the recyclable support pile 1 can be recycled, it can be constructed and recycled in multiple construction sections of the pipe gallery project in turn, and can play a recycling effect during the construction process, and can be used in the entire pipe gallery. After the project construction is completed, it can be finally recycled, thereby reducing the cost and construction period, which is conducive to improving construction efficiency and convenience, effectively improving resource utilization, and avoiding resource waste.

At the same time, the bridge-type prestressed support system 4 can also be used repeatedly in multiple construction sections due to its connection with the crown beam 3, and when it carries a load, it can transfer the force of the load to the crown beam 3 and the recoverable support piles 1, so as to better ensure the reliability of its load bearing. During the construction process of the construction section, the soil 103 excavated in the foundation pit can be piled up on the bearing surface of the bridge-type prestressed support system 4, so that the soil 103 can be processed nearby without being transported out of the foundation pit, and can be stored in the foundation pit. In the post-construction stage of the construction section, the soil 103 on the bearing surface is directly used for backfilling, thereby avoiding repeated and ineffective transportation of the soil 103, thereby reducing construction costs and carbon emissions, and improving construction efficiency. Moreover, the second prestressed structure 5 is provided in the bridge-type prestressed support system 4, which can better ensure its bending stiffness in the vertical direction, and further ensure its reliability when carrying loads.

Since the first prestressed structure 2 can actively improve the bending resistance of the recoverable support pile 1 and the crown beam 3, the design of the section size of the recoverable support pile 1 and the crown beam 3 can be further optimized so that it does not need It is designed in a larger size according to the bending resistance requirements, thereby improving its design flexibility and reducing its production cost.

In some embodiments, as shown in FIGS. 1-3 , the bridge-type prestressed support system 4 includes a plurality of bearing assemblies 41, and the plurality of bearing assemblies 41 are distributed along the length direction L of the crown beam 3. The two ends of the bearing assemblies 41 They are respectively connected to the crown beam 3 through the supporting components, and the second prestressed structure 5 is arranged on the bearing component 41 .

It can be understood that the bearing assembly 41 can provide a bearing surface for bearing the soil mass 103, thereby improving the load-bearing performance, and at the same time, the support assembly can provide a stable support effect on the bearing assembly 41, which can bear the pressure of the soil mass 103, It can also be transferred to the recoverable support pile 1. Compared with conventional supporting structures, the load-bearing component 41 has better load-bearing capacity.

In some embodiments, as shown in FIGS. 1-3 , the bearing assembly 41 includes a plurality of bridge deck girders 411 and support plates 413 . A plurality of deck girders 411 are distributed along the length direction of the crown girder 3, and the two ends of each bridge deck girder 411 are respectively connected to the crown girder 3 through a diagonal support 412, and the second prestressed structure 5 is arranged on the bridge deck main girder. Beam 411 on. The supporting boards 413 are arranged on the plurality of bridge girders 411 , and the top walls of the supporting boards 413 form a bearing surface.

In some embodiments, the support assembly may be a diagonal stand 412 .

It can be understood that the main beam 411 of the bridge deck has good strength and rigidity, so as to provide stable support, and the main beam 411 of the bridge deck is connected with the crown beam 3 through the inclined support 412, so that the bearing plate 413 can be supported The pressure of the soil body 103 is transmitted to the oblique support 412, and the oblique support 412 can divide the pressure of the soil body 103 into horizontal thrust and vertical pressure, which not only forms a supporting force for the recoverable support pile 1 on both sides, but also can The horizontal displacement of the recoverable support pile 1 is regulated to better ensure the reliable load bearing of the soil 103 and the reliable support effect of the recoverable support pile 1 .

In some embodiments, one second prestressed structure 5 may be provided on one bridge deck girder 411 .

In some embodiments, as shown in FIG. 2 , the bearing assembly 41 further includes a plurality of connecting beams 414, and the plurality of connecting beams 414 are arranged on the main beam 411 of the bridge deck at intervals. Between two adjacent connecting beams 414, a A support plate 413. It can be understood that the connecting beam 414 can further strengthen the strength of the bearing assembly 41 so that the support plate 413 can support the excavated soil 103 more reliably.

In some embodiments, as shown in FIG. 2 , the deck girder 411 includes two H-shaped steel bars 4111 and stiffeners 4113 . The side faces of the two H-shaped steels 4111 are connected in pairs by connecting plates 4112 . Stiffeners 4113 are set inside the H-shaped steel 4111.

It can be understood that the H-shaped steel 4111 is convenient to connect with the crown beam 3 , and also has good strength and rigidity, so as to facilitate reliable support for the soil body 103 . The connecting plate 4112 can facilitate the fixed connection of two adjacent H-shaped steels 4111, so as to improve the connection stability of the two adjacent H-shaped steels 4111, thereby improving the reliability of the main girder 411 of the bridge deck. Since the H-shaped steel 4111 has a large space inside, arranging a plurality of stiffeners 4113 can further increase the strength and rigidity of the H-shaped steel 4111 , thereby further improving the reliability of the bridge deck girder 411 .

In some embodiments, as shown in FIGS. 1-3 , the bridge-type prestressed support system 4 further includes a plurality of high-strength steel rods 42 and a displacement adjuster 43 . Both ends of the high-strength steel rod 42 are respectively connected to the crown beam 3 , and the two ends of each high-strength steel rod 42 are respectively set corresponding to a diagonal support 412 . The displacement adjuster 43 is arranged on the high-strength steel rod 42 , and the displacement adjuster 43 is configured to control part of the thrust force applied to the crown beam 3 by the high-strength steel rod 42 carrying the soil 103 .

It can be understood that when the load-bearing assembly 41 does not carry the soil mass 103 or bears a small amount of soil mass 103, the pile tops of the recoverable support piles 1 on both sides of the foundation pit will move toward the foundation under the action of the lateral pressure on the outside of the foundation pit. The trend of the horizontal displacement in the pit, at this time the displacement controller can control the high-strength steel rod 42 without force. When the soil mass 103 carried on the bearing assembly 41 gradually increases, the soil mass 103 will exert a force on the bearing assembly 41, and at the same time, the bearing assembly 41 is connected with the recoverable support pile 1, so that the recoverable support pile 1 Under this force, the pile tends to have a large horizontal displacement towards the outside of the foundation pit. In this embodiment, since high-strength steel rods 42 are also arranged between the two crown beams 3, the high-strength steel rods 42 are connected with the two recyclable support piles 1 oppositely arranged through the crown beams 3. Under the action of the device 43, the high-strength steel rod 42 can bear part of the thrust of the force of the soil 103, thereby effectively controlling the displacement of the top of the recoverable support pile 1 towards the outside of the foundation pit, and preventing the load-bearing component 41 from pushing the recoverable support pile 1 to the outside of the foundation pit. The extrapolation of the top of the pile 1 further ensures the reliability of the recoverable support pile 1 and the bridge prestressed support system 4 .

In some embodiments, the two high-strength steel rods 42 can move freely in the opposite direction, and are restrained in the opposite direction, so as to generate tension between them.

In some embodiments, as shown in FIGS. 4 and 5 , the first prestressed structure 2 includes two first anchors 21 and first steel strands 22 arranged at intervals. The first anchor 21 is arranged in the recoverable support pile 1 and the crown beam 3 . Two ends of the first steel strand 22 are respectively fixedly connected with two first anchors 21 .

It can be understood that the two first anchors 21 are fixedly connected to the recoverable support pile 1 or the crown beam 3, so that the steel strands fixedly connected with the two first anchors 21 can be fixed in one or two first The anchorage 21 is prestressed and stretched, so as to realize the tension effect, and then improve the bending resistance of the recoverable support pile 1, which is conducive to improving the support effect of the recoverable support pile 1 and improving the strength of the crown beam 3. Bending resistance, so as to resist the lateral pressure caused by the soil 103 on the recoverable support pile 1 , which is beneficial to improve the support effect of the recoverable support pile 1 .

For example, the recoverable support pile 1 is extended vertically, and the crown beam 3 is extended horizontally. Carry out the prestressed stretching of the first steel strand 22, carry out the prestressed tension of the first steel strand 22 at the two first anchorages 21 places at the two ends of the crown beam 3, in other construction occasions, also can It is adjusted according to the actual construction situation, and no specific limitation is required.

In some embodiments, as shown in FIG. 2 and FIG. 3 , the second prestressed structure 5 includes two second anchors 51 arranged at intervals, a second steel strand 52 and a plurality of support rods 53 distributed at intervals. The second anchor 51 is arranged in the bridge type prestressed support system 4 . Two ends of the second steel strand 52 are respectively fixedly connected with two second anchors 51 . One end of the support rod 53 is connected with the bridge type prestressed support system 4, and the other end of the support rod 53 is connected with the steel strand.

It can be understood that the two second anchors 51 are fixedly connected in the bridge type prestressed support system 4, so that the steel strands fixedly connected with the two second anchors 51 can be fixed in one or two second anchors 51 Prestressed stretching is carried out at the place, so as to realize the tension effect, thereby improving the bending resistance of the bridge type prestressed support system 4. In addition, the steel strands will also exert pressure on the support rod 53 during the prestressed stretching process to further The bending stiffness of the bridge-type prestressed support system 4 in the vertical direction is improved, thereby ensuring the ability of the bridge-type prestressed support system 4 to bear the soil 103 .

For example, in this embodiment, the two second anchorages 51 are connected by multiple straight sections of recoverable steel pipes, and the second steel strand 52 is passed through the recoverable steel pipes, thereby facilitating the connection between the support rod 53 and the recoverable steel pipes. connected so as to realize that the steel strands can also exert pressure on the support rod 53 when the steel strand is prestressed and stretched, so as to improve the vertical bending stiffness of the bridge prestressed support system 4 .

In the embodiment of the present application, the first prestressed structure 2 and the second prestressed structure are not limited to the above description, for example, the first prestressed structure 2 can additionally be provided with a plurality of support bars 53, and the second prestressed 5. Only the second anchorage 51 and the second steel strand 52 can be set, and the first prestressed structure 2 and the second prestressed structure 2 in the recoverable support pile 1, the crown beam 3 and the bridge prestressed support system 4 The specific structure of structure 5 can be adjusted according to actual construction requirements, construction difficulty and other on-site reasons, without specific limitations.

In some embodiments, the crown beam 3 is provided with multiple first prestressed structures 2 , and the bridge type prestressed support system 4 is provided with multiple second prestressed structures 5 .

In some embodiments, the entire crown beam 3 can be formed by connecting multiple crown beam segments back and forth due to its relatively long length, and a first prestressing structure 2 is arranged in each crown beam segment.

It can be understood that, in some construction sections, the crown beam 3 and the bridge-type prestressed support system 4 usually have relatively long lengths. Therefore, setting a plurality of first prestressed structures 2 in the crown beam 3 can further improve the prestressed tension effect, so as to further improve the bending resistance of the crown beam 3, improve its ability to resist lateral pressure, and further ensure the support system. reliability. Setting a plurality of second prestressed structures 5 in the bridge prestressed support system 4 can further improve the bending stiffness of the bridge prestressed support system 4, thereby better ensuring that the bridge prestressed support system 4 bears soil mass 103 to prevent the soil body 103 from falling during construction and ensure construction safety.

In some embodiments, as shown in Fig. 4 and Fig. 5, the recoverable support pile 1 includes a recoverable steel pipe 11 and plastic concrete 12 arranged on the outside of the recoverable steel tube 11, and two adjacent recoverable support piles The plastic concrete 12 of the pile 1 interlocks with each other, and the prestressed structure is set in the recyclable steel pipe 11 .

It can be understood that the recyclable steel pipe 11 can be easily removed after the construction of a construction section is completed, so as to be applied to the construction of the next section of recyclable support pile 1, so as to improve the turnover rate of construction materials and reduce construction costs. At the same time, since the plastic concrete 12 of two adjacent recoverable support piles 1 interlocks with each other, multiple recoverable support piles 1 can be overlapped with each other to achieve a better water-stop effect, and the recoverable steel pipe 11 It can provide resistance to the recoverable support pile 1 to bear the pressure on both sides of the foundation pit and ensure the safe construction of the pipe gallery 102 in the foundation pit.

In addition, the support system formed by the recyclable steel pipe 11 and the plastic concrete 12 has the characteristics of modular assembly, recyclability and fast construction speed, so it is suitable for segmental construction of multiple construction sections in the pipe gallery project, thus facilitating After the construction of the previous construction section is completed, it is removed to the next construction section for construction. And the foundation pit depth of the pipe gallery project is usually 6-7m, and its depth is also conducive to the construction of the support system formed by the recyclable steel pipe 11 and the plastic concrete 12, which better ensures the support quality.

In some embodiments, as shown in FIG. 4 and FIG. 5 , the cross section of the recyclable steel pipe 11 is rectangular, the crown beam 3 is made of steel, and the cross section of the crown beam 3 is rectangular.

It can be understood that since the crown beam 3 and the recoverable steel pipe 11 have rectangular cross-sections, it is convenient to chisel out the local plastic concrete 12 on the inside of the top of the recoverable support pile 1 during construction, so that the recoverable support The recyclable steel pipe 11 of the pile 1 is exposed, which can not only facilitate the lamination of the crown beam 3 and the recyclable steel pipe 11 and the fixed connection by bolts, but also facilitate the formation of steps on the recyclable support pile 1, thereby providing partial support for the crown beam 3 As a result, the reliable connection between the crown beam 3 and the recoverable support pile 1 is ensured.

As shown in Figure 6, this application also discloses a construction method of a recyclable prestressed support system, based on the aforementioned recyclable prestressed support system, including: S1, on both sides of the foundation pit in the construction section Set up the enclosure structure; S2, fixedly connect the crown beams (two crown beams) on the inside of the top of the two rows of enclosure structures; S3, install bridge-type prestressed support system 4 on the crown beams; S4, carry out the earthwork in the foundation pit of the construction section Excavation, during the excavation process, part of the soil 103 in the pit is stacked on the bearing surface of the bridge prestressed support system 4, and the first prestressed structure 2 and the bridge prestressed structure 2 in the enclosure structure are applied (as required). The prestress of the second prestressed structure 5 in the support system 4; S5, after the construction of the underground structure in the foundation pit of the construction section, backfill the soil 103 in the construction section (the foundation pit of the construction section); S6, release the first prestressed Prestressing of the stress structure 2 (e.g. the first prestress structure 2 within the building envelope) and the second prestress structure 5 (e.g. the second prestress structure 5 within the bridge prestressed bracing system), demolition of the bridge prestressed bracing system 4. Crown beam 3 and part of the enclosure structure; S7. Repeat steps S1-S6 in the next construction section until the construction of the entire construction section is completed.

For example, in the construction method of this embodiment, the first prestressed structure 2 is preset in the enclosure structure and the crown beam 3, the second prestressed structure 5 is preset in the bridge prestressed support system 4, and the enclosure The structure and the crown beam 3 are installed with the first prestressed structure 2 when the components leave the factory, and the second prestressed structure 5 built in the bridge prestressed support system 4 is assembled on site. The structure 2 is prestressed when it leaves the factory, and the first prestressed structure 2 in the enclosure structure and the second prestressed structure 5 in the bridge prestressed support system 4 are prestressed on site as required during the construction process. In other embodiments of the present application, the specific processing and application methods and order of the prestressed structures in the multiple components can be determined according to actual requirements.

In addition, in the construction method of this embodiment, the crown beam 3 includes a plurality of standard sections, and each standard section is provided with a first prestressed structure 2, so that the site only needs to place the prestressed multiple standard sections Connect in sequence to form the crown beam 3. In other embodiments of the present application, the crown beam 3 can also be connected with a plurality of standard sections in advance, and its specific processing and connection sequence can be determined according to actual needs.

Example:

The recyclable prestressed support system and construction method of a specific embodiment of the present application are described below with reference to FIGS. 1-6 .

The recoverable prestressed support system of this embodiment includes two rows of enclosure structures, two crown beams 3 , a bridge-type prestressed support system 4 , a first prestressed structure 2 and a second prestressed structure 5 .

Two rows of enclosure structures are arranged at intervals on both sides of the foundation pit, and each row of enclosure structures includes a plurality of retrievable support piles 1 that are sequentially engaged, and each retrievable support pile 1 is provided with a first prestressed structure 2. A crown beam 3 is connected to a plurality of recoverable support piles 1 of each row of enclosure structures, and a first prestressed structure 2 is arranged inside the crown beam 3 . The recyclable support pile 1 includes a recyclable steel pipe 11 and plastic concrete 12 arranged on the outside of the recyclable steel pipe 11, the plastic concrete 12 of two adjacent recyclable support piles 1 interlocks with each other, and the prestressed structure is located at the In the recovery steel pipe 11.

The first prestressed structure 2 includes two first anchors 21 and first steel strands 22 arranged at intervals. The first anchor 21 is arranged in the recoverable support pile 1 and the crown beam 3 . Two ends of the first steel strand 22 are respectively fixedly connected with two first anchors 21 .

The two ends of the bridge-type prestressed support system 4 are respectively arranged on a crown beam 3 and connected with the crown beam 3. The bridge-type prestressed support system 4 is provided with a bearing surface for bearing the soil 103. The bridge-type prestressed support system 4 is provided with a second prestressed structure 5 . The bridge type prestressed support system 4 includes a plurality of bearing assemblies 41, and the plurality of bearing assemblies 41 are distributed along the length direction of the crown beam 3. The two ends of the bearing assemblies 41 are respectively connected with the crown beam 3 through the support assemblies. Set on the carrier assembly 41. The bearing assembly 41 includes a plurality of deck girders 411 and support plates 413 . A plurality of deck girders 411 are distributed along the length direction of the crown girder 3, and the two ends of each bridge deck girder 411 are respectively connected to the crown girder 3 through a diagonal support 412, and the second prestressed structure 5 is arranged on the bridge deck main girder. Beam 411 on. The supporting boards 413 are arranged on the plurality of bridge girders 411 , and the top walls of the supporting boards 413 form a bearing surface. The deck girder 411 includes two H-shaped steels 4111 and stiffeners 4113 . The side faces of the two H-shaped steels 4111 are connected in pairs by connecting plates 4112 . Stiffeners 4113 are set inside the H-shaped steel 4111. The bridge prestressed support system 4 also includes a plurality of high-strength steel rods 42 and a displacement adjuster 43 . Both ends of the high-strength steel rod 42 are respectively connected to the crown beam 3 , and the two ends of each high-strength steel rod 42 are respectively set corresponding to a diagonal support 412 . The displacement adjuster 43 is arranged on the high-strength steel rod 42 , and the displacement adjuster 43 is configured to control part of the thrust force applied to the crown beam 3 by the high-strength steel rod 42 carrying the soil 103 .

The second prestressed structure 5 includes two second anchors 51 arranged at intervals, a second steel strand 52 and a plurality of support rods 53 distributed at intervals. The second anchor 51 is arranged in the bridge type prestressed support system 4 . Both ends of the second steel strand 52 are fixedly connected to the second anchor 51 respectively. One end of the support rod 53 is connected to the bridge type prestressed support system 4, and the other end of the support rod 53 is connected to the steel strand.

The construction method of the recyclable prestressed support system of the present embodiment comprises:

1. In a construction section of the pipe gallery project, the hole forming process is carried out along the edge of the foundation pit, the recyclable steel pipe 11 is hoisted in the hole, and the plastic concrete 12 is poured to form an interlocking enclosure structure.

2. Cut away part of the plastic concrete 12 near the inner side of the foundation pit on the top of the recyclable support pile 1, so that the recyclable steel pipe 11 is exposed, and the crown beam 3 is fixedly connected and installed on the exposed recyclable steel pipe 11 to form a recyclable Type support pile 1 and the integral body of crown beam 3.

3. Assemble the bridge-type prestressed support system 4 on site, and connect the two ends of the bridge-type prestressed support system 4 with the two crown beams 3 .

4. With the excavation of the foundation pit, cover the excavated part of the soil 103 on the bridge-type prestressed support system 4, and apply the prestress of the bridge-type prestressed support system 4 as required, and recyclable support piles 1 prestress.

5. Excavate the foundation pit to the bottom, and construct the bottom plate 101 and the pipe gallery 102 in it, and backfill the soil 103 on the bridge prestressed support system 4 into the foundation pit after the construction is completed.

6. Release the prestress of the first prestressed structure 2 in the enclosure structure and the second prestressed structure 5 in the bridge-type prestressed support system 4, remove the bridge-type prestressed support system 4 and the crown beam 3, and pull out the recyclable The recyclable steel pipe 11 in the support pile 1 is backfilled and compacted in the plastic concrete 12 .

7. Repeat steps 1-6 until the construction of the entire construction section is completed, and recover the recyclable prestressed support system after the construction is completed.

The embodiment of the present application discloses a recyclable prestressed support system and a construction method, which can reduce construction costs and improve construction efficiency and construction quality.

In the embodiment of the present application, since the recyclable support pile can be recycled, it can be constructed and recycled in multiple construction sections of the pipe gallery project in turn, and can play a recycling effect during the construction process, and can be used in the entire pipe gallery project. After the construction is completed, it can be finally recycled, thereby reducing the cost and the construction period, which is conducive to improving the construction efficiency and convenience, and effectively improving the resource utilization rate, avoiding the problem of resource waste. At the same time, the bridge-type prestressed support system can also be used repeatedly in multiple construction sections due to its connection with the crown beam, and when it bears a load, it can transfer the force of the load to the crown beam and the recoverable support piles, thereby The reliability of its bearing load is better guaranteed. During the construction process of the construction section, the soil excavated in the foundation pit can be piled up on the bearing surface of the bridge-type prestressed support system, so that the soil can be processed nearby without being transported out of the foundation pit, and can be placed in the construction section. In the later stage of construction, the soil on the bearing surface is directly used for backfilling, thereby avoiding repeated and invalid transportation of the soil, thereby reducing construction costs and carbon emissions. Moreover, a second prestressed structure is provided in the bridge-type prestressed support system, which can better ensure its bending stiffness in the vertical direction and further ensure its reliability when carrying loads. Since the first prestressed structure can actively improve the bending resistance of the recoverable support piles and crown beams, the section size design of the recoverable support piles and crown beams can be further optimized, so that it does not need to be designed according to the bending resistance requirements. For larger size, thus improving its design flexibility and reducing its production cost.

In the description of this specification, descriptions with reference to the terms "some embodiments", "other embodiments" and the like mean that specific features, structures, materials or characteristics described in connection with the embodiments or examples are included in at least one embodiment of the present application or example. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

The above content is only part of the embodiments of the application. For those of ordinary skill in the art, according to the concept of the present invention, there will be changes in the specific implementation and application scope. The content of this specification should not be interpreted as a limitation of the application .

Claims

A recyclable prestressed support system comprising:

Two rows of enclosure structures, the two rows of enclosure structures are arranged at intervals on both sides of the foundation pit, each row of enclosure structures includes a plurality of recoverable support piles (1) that are sequentially engaged, and each of the recoverable The type support pile (1) is provided with a first prestressed structure (2);

Two crown beams (3), one of the crown beams (3) in the two crown beams (3) is connected to a plurality of the recoverable support piles (1) of each row of the enclosure structure ), each of the crown beams (3) is provided with the first prestressed structure (2);

A bridge-type prestressed support system (4), the two ends of the bridge-type prestressed support system (4) are respectively arranged on one of the crown beams (3) in the two crown beams (3) and are connected to the two crown beams (3) The two crown beams (3) are connected, the bridge type prestressed support system (4) is provided with a bearing surface for bearing soil (103), and the bridge type prestressed support system (4) is provided with a first Two prestressed structures (5).
The recyclable prestressed support system according to claim 1, wherein, the bridge type prestressed support system (4) comprises a plurality of load-bearing components (41), and a plurality of load-bearing components (41) along the The two crown beams (3) are distributed in the length direction, and the two ends of each load-bearing component (41) are respectively connected to the two crown beams (3) through a support component, and the second prestressed structure (5) It is arranged on each bearing component (41) in the plurality of bearing components (41).
The recyclable prestressed support system according to claim 2, wherein each load-bearing component (41) in the plurality of load-bearing components (41) comprises:

A plurality of bridge deck girders (411), a plurality of said bridge deck girders (411) are distributed along the length direction of said two crown girders (3), each of said bridge deck girders (411) at both ends Connect with a crown girder (3) through an oblique support (412) respectively, and the second prestressed structure (5) is arranged on each bridge deck girder (411) in the plurality of bridge deck girders ( 411) on;

A support plate (413), the support plate (413) is arranged on a plurality of said main girders (411) of the bridge deck, and the top wall of the support plate (413) forms the bearing surface.
The recyclable prestressed support system according to claim 3, wherein each bridge deck girder (411) in the plurality of bridge deck girders (411) comprises:

Two H-shaped steels (4111), the sides of the two H-shaped steels (4111) are joined together through connecting plates (4112);

Stiffeners (4113), the stiffeners (4113) are arranged inside the two H-shaped steels (4111).
The recyclable prestressed support system according to claim 3, wherein the bridge type prestressed support system (4) further comprises:

A plurality of high-strength steel rods (42), the two ends of each of the high-strength steel rods (42) in the plurality of high-strength steel rods (42) are respectively connected to the two crown beams (3), and each The two ends of the high-strength steel rod (42) are respectively set corresponding to one of the inclined supports (412);

Displacement adjuster (43), described displacement adjuster (43) is located on described each high-strength steel rod (42), and described displacement adjuster (43) is arranged to control described each high-strength steel rod (42) It bears part of the thrust applied by the soil body (103) to the two crown beams (3).
The recyclable prestressed support system according to claim 1, wherein the first prestressed structure (2) comprises:

Two first anchors (21) arranged at intervals, the two first anchors (21) are arranged in the plurality of recoverable support piles (1) and the two crown beams (3) Inside;

The first steel strand (22), the two ends of the first steel strand (22) are respectively fixedly connected with the two first anchors (21).
The recyclable prestressed support system according to claim 1, wherein the first prestressed structure (2) comprises:

Two first anchorages (21) arranged at intervals;

The first steel strand (22), the two ends of the first steel strand (22) are respectively fixedly connected with the two first anchors (21).
The recoverable prestressed support system according to any one of claims 1-7, wherein each recoverable support pile (1) in the plurality of recoverable support piles (1) One first prestressed structure (2) is arranged inside, and a plurality of first prestressed structures (2) are arranged inside each of the two crown beams (3).
The recyclable prestressed support system according to claim 1, wherein the second prestressed structure (5) comprises:

Two second anchors (51) arranged at intervals, the two second anchors (51) are arranged in the bridge type prestressed support system (4);

A second steel strand (52), the two ends of the second steel strand (52) are fixedly connected to the two second anchors (51) respectively;

A plurality of supporting rods (53) distributed at intervals, one end of each of the supporting rods (53) is connected with the bridge type prestressed support system (4), and the other end of each of the supporting rods (53) is connected with the The second steel strand (52) is connected.
The recyclable prestressed support system according to claim 1, wherein, each of the two crown beams (3) is provided with a plurality of first prestressed structures (2) ), the bridge type prestressed support system (4) is provided with multiple second prestressed structures (5).
The recoverable prestressed support system according to claim 1, wherein each recoverable support pile (1) in the plurality of recoverable support piles (1) comprises a recoverable steel pipe (11 ) and the plastic concrete (12) located on the outside of the recyclable steel pipe (11), two adjacent recyclable support piles (1) in the plurality of recyclable support piles (1) The said plastic concrete (12) interlocks with each other, and said first prestressed structure (2) is arranged in said recyclable steel pipe (11).
A construction method of a recyclable prestressed support system, based on the recyclable prestressed support system according to any one of claims 1-11, comprising:

Step 1 (S1), respectively setting enclosure structures on both sides of the foundation pit in the construction section;

Step 2 (S2), fixing and connecting the crown beam (3) on the inner side of the top of the enclosure structure;

Step 3 (S3), installing a bridge-type prestressed support system (4) on the crown beam (3);

Step 4 (S4), excavating the earth in the foundation pit of the construction section, stacking part of the soil (103) in the pit on the bearing surface of the bridge-type prestressed support system (4) during the excavation process, and applying the surrounding The prestressing of the first prestressing structure (2) in the protective structure and the second prestressing structure (5) in the bridge prestressing support system (4);

Step 5 (S5), after the construction of the underground structure in the construction section is completed, backfill the soil (103) into the construction section;

Step 6 (S6), releasing the prestress of the first prestress structure (2) in the enclosure structure and the second prestress structure (5) in the bridge prestress support system (4), Removing the bridge type prestressed support system (4), the crown beam (3) and part of the enclosure structure;

Step 7 (S7), repeat step 1 (S1)-step 6 (S6) in the next construction section until the construction of the entire construction section is completed.