CN212316934U

CN212316934U - Supporting member and foundation pit supporting system

Info

Publication number: CN212316934U
Application number: CN202020388786.XU
Authority: CN
Inventors: 林蓼; 徐军林; 闫顺; 费金新; 杨宗元
Original assignee: China Railway Siyuan Survey and Design Group Co Ltd
Current assignee: China Railway Siyuan Survey and Design Group Co Ltd
Priority date: 2020-03-24
Filing date: 2020-03-24
Publication date: 2021-01-08
Anticipated expiration: 2030-03-24

Abstract

The application provides a supporting member, a foundation pit supporting system and a construction method of a subway station. The two chord members are arranged at intervals up and down, two ends of each chord member are respectively connected to the enclosure body of the foundation pit supporting system, and two ends of the chord members on at least the upper part are detachably connected with the enclosure body. The connecting piece is connected between the upper chord member and the lower chord member. In the supporting member that this application provided, owing to adopted prefabricated chord member and connecting piece concatenation to form, therefore can demolish used repeatedly with last chord member after the construction is accomplished, the last chord member then can be used to in the station roof, continue to provide the support for the station roof to the construction degree of difficulty has been reduced.

Description

Supporting member and foundation pit supporting system

Technical Field

The application relates to the technical field of subway station construction, in particular to a supporting member and a foundation pit supporting system.

Background

In the process of the construction of subway station, in order to prevent the earth around the foundation pit from collapsing and flowing into the foundation pit, the development of normal station construction work is influenced, and the foundation pit needs to be supported. Generally, an enclosure is used for enclosure before excavation, and then a supporting member is used for supporting the enclosure after excavation to prevent the enclosure from being failed, wherein the supporting member is used as a part of an inner supporting system of a foundation pit and bears a large amount of supporting work.

In the prior art, the supporting members are usually integrally formed by pouring concrete, so that the supporting members need to be completely dismantled after supporting work is finished, the construction period is long, the workload is large, and the result of high construction difficulty is caused.

SUMMERY OF THE UTILITY MODEL

In view of this, the embodiments of the present application are expected to provide a supporting member and a foundation pit supporting system to solve the problem of high difficulty in the construction of a subway station.

In order to achieve the above object, an aspect of the embodiments of the present application provides a supporting member for use in a foundation pit supporting system for constructing a subway station. The support member includes: the two chord members are arranged at intervals up and down, two ends of each chord member are respectively connected to the enclosure of the foundation pit supporting system, and two ends of at least the upper chord member are detachably connected with the enclosure; and a connecting member connected between the chord member at the upper portion and the chord member at the lower portion.

Further, the chord member comprises a plurality of spliced middle chords and end chords which are respectively spliced at two ends of the middle chords; and the adjacent middle chords and the end chords and the middle chords are connected through flange structures.

Further, the connector includes: the two ends of the first connecting piece are respectively orthogonally connected with the chord member bar at the upper part and the chord member bar at the lower part; and one end of the second connecting piece is arranged at the joint of one first connecting piece and the chord member at the upper part, and the other end of the second connecting piece is arranged at the joint of the other adjacent first connecting piece and the chord member at the lower part.

Further, two adjacent second connecting pieces are symmetrically arranged relative to the first connecting piece; and/or the distance between two adjacent first connecting pieces is 1 m-3 m.

Furthermore, a middle splicing unit is formed by the middle chord on the upper part, the middle chord on the lower part and at least one first connecting piece; and/or one end part splicing unit is formed by one end part chord member on the upper part, one end part chord member on the lower part and at least one first connecting piece.

Furthermore, the connecting pieces also comprise third connecting pieces, and the two third connecting pieces are symmetrically arranged in the middle of the supporting member; one end of each third connecting piece is arranged in the middle of the chord member at the upper part, and the other end of each third connecting piece is arranged at the connecting part of the adjacent first connecting piece and the chord member at the lower part; or one end of each third connecting piece is arranged in the middle of the chord member at the lower part, and the other end of each third connecting piece is arranged at the joint of the adjacent first connecting piece and the chord member at the upper part.

The supporting member that this application embodiment provided forms through adopting prefabricated chord member and connecting piece concatenation to after strutting the work and accomplishing, can demolish upper chord member and connecting piece, remain the chord member of lower part. The chord member at the lower part is used as a part of the station roof and continues to provide support for the station roof. Therefore, the dismantling work of the chord member at the lower part can be omitted, the resource utilization rate is improved, the construction time is saved, and the construction difficulty is reduced.

Another aspect of the embodiments of the present application provides a foundation pit supporting system, including: the enclosure body is internally excavated to form a foundation pit; and the supporting members of any of the above embodiments, wherein a plurality of the supporting members are arranged on the enclosure body at intervals and above the foundation pit.

Furthermore, the enclosure body comprises an enclosure wall body, a crown beam and a retaining wall, the enclosure wall body is internally excavated to form the foundation pit, the crown beam is connected to the top end of the enclosure wall body, and the retaining wall is connected to the upper part of the crown beam; the chord member on the upper part is detachably connected to the crown beam, and the chord member on the lower part is connected to the enclosure wall.

Furthermore, the crown beam is provided with a first embedded connecting piece, and the chord member at the upper part is detachably connected with the crown beam through the first embedded connecting piece.

Furthermore, the foundation pit supporting system also comprises a supporting body positioned in the foundation pit, and two ends of the supporting body are connected to the two opposite walls of the enclosure body.

The foundation pit supporting system provided by the embodiment of the application has the same technical effect due to the adoption of any one of the supporting members, and the details are not repeated.

Drawings

Fig. 1 is a schematic structural diagram of a foundation pit supporting system according to an embodiment of the present disclosure;

FIG. 2a is a front view of an intermediate chord in one orientation according to one embodiment of the present application;

FIG. 2b is a side view of the flange structure of FIG. 2 a; and

fig. 3 is a flowchart of a construction method of a subway station according to an embodiment of the present application.

Description of reference numerals:

100. a support member; 1. a chord member; 11. a middle chord; 12. an end chord; 21. a middle splicing unit; 22. an end splicing unit; 3. a flange structure; 31. mounting holes; 4. a connecting member; 41. a first connecting member; 42. a second connecting member; 43. and a third connecting member.

200. An enclosure; 210. enclosing a wall body; 211. a second pre-buried connecting piece; 220. a crown beam; 221. a first pre-buried connecting piece; 230. a retaining wall; 300. and a support body.

410. A station roof; 420. a middle plate of a station; 430. a station floor.

Detailed Description

It should be noted that, in the present application, technical features in examples and embodiments may be combined with each other without conflict, and the detailed description in the specific embodiment should be understood as an explanation of the gist of the present application and should not be construed as an improper limitation to the present application.

The directional terms described in this application are used only for convenience in describing the application and for simplicity in description, and do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore should not be construed as limiting the application.

In the process of constructing the foundation pit of the subway station, the enclosure body 200 is generally constructed before excavation, and then the foundation pit supporting system is continuously constructed in the foundation pit while excavation is performed from top to bottom. And when the lowest end is excavated, the subway station is built from bottom to top, and in the process of building the subway station, part of the structure of the foundation pit supporting system is dismantled from bottom to top. The support member 100 serves as a first support of the excavation supporting system, which is installed first and is removed last when it is required to construct the station roof 410 last, so that the support member 100 takes important supporting work in the excavation supporting system. In the prior art, the supporting member 100 is usually cast in situ with concrete, and after the supporting work is completed, the supporting member 100 is usually removed by chiseling, and then the station roof 410 is reconstructed at a corresponding position. Therefore, not only is a longer construction period caused, but also a certain degree of resource waste is caused.

In view of the above, a first aspect of the embodiments of the present application provides a supporting member 100 for use in an excavation supporting system for constructing a subway station. Referring to fig. 1, the supporting member 100 includes a chord member 1 and a connecting member 4. The two chord members 1 are arranged at intervals up and down, two ends of each chord member 1 are respectively connected to the enclosure 200 of the foundation pit supporting system, and two ends of at least the upper chord member 1 are detachably connected with the enclosure 200. The connecting piece 4 is connected between the upper chord member 1 and the lower chord member 1.

In one embodiment, please refer to fig. 1, which illustrates an application of the support member 100 provided herein in an excavation supporting system. The foundation pit supporting system comprises an enclosure body 200 and supporting members 100, a foundation pit is formed by digging in the enclosure body 200, and a plurality of supporting members 100 are arranged on the enclosure body 200 at intervals and located above the foundation pit. By providing the supporting member 100 between two parallel walls in the enclosure 20, a resistance force perpendicular to the inner wall of the pit is provided to the enclosure 200, thereby improving the supporting strength of the enclosure 200. In order to ensure sufficient supporting strength of the enclosure 200, the supporting member 100 is required to have high strength. The support member 100 provided by the present application is connected between the upper and lower parallel chord members 1 by using the prefabricated connecting pieces 4 to form the support member 100.

When the station roof 410 needs to be constructed, the upper chord members 1 and the connecting members 4 are removed, the lower chord members 1 are retained, a plurality of chord members 1 arranged at intervals in the horizontal direction are connected with a plurality of connecting beams (not shown) in a staggered manner to form a part of the frame structure of the station roof 410, and finally concrete is poured on the frame structure to form the station roof 410.

The supporting member 100 provided by the embodiment of the application is formed by splicing the prefabricated chord members 1 and the prefabricated connecting members 4, so that after the supporting work is completed, the chord members 1 and the prefabricated connecting members 4 on the upper portion can be detached, the chord members 1 on the lower portion are reserved, and the chord members 1 on the lower portion are used as a part of the station roof 410 to continuously provide support for the station roof 410. Therefore, the upper chord member 1 can be repeatedly used after being dismantled, the dismantling work of the lower chord member 1 can be omitted, the resource utilization rate is improved, the construction time is saved, and the construction difficulty is reduced.

Preferably, in order to ensure the supporting strength of the chord members 1 and the connecting members 4 while reducing the cost, the chord members 1 and the connecting members 4 are each cast with concrete.

In an embodiment, referring to fig. 1, the present application provides a support member 100, in which a chord member 1 includes a plurality of middle chords 11 and end chords 12 respectively connected to two ends of the middle chords 11. The adjacent middle chords 11 and the end chords 12 and the middle chords 11 are connected by the flange structure 3, please refer to fig. 2a and 2 b. The chord members 1 are formed by splicing a plurality of middle chords 11 and end chords 12 at two ends, so that the number of the middle chords 11 can be flexibly selected in the assembling process according to the required length during construction.

Specifically, referring to fig. 2a and 2b, the flange structures 3 are disposed at the ends of the middle chords 11 or the end chords 12, mounting holes 31 are formed around the flange structures near the boundaries, the flange structures 3 are fitted between adjacent middle chords 11 or between the middle chords 11 and the end chords 12, and the mounting holes 31 of two flange structures 3 are aligned and then fastened by using fasteners. When the fastener needs to be detached, the fastener is detached. This connected mode is simple high-efficient, and the dismouting of being convenient for is convenient for reuse middle chord 11 and tip chord 12.

In one embodiment, referring to fig. 1, the present application provides a support member 100, in which the connection member 4 includes a first connection member 41 and a second connection member 42. The first connecting member 41 has both ends orthogonally connected to the upper chord member 1 and the lower chord member 1, respectively. One end of the second connecting piece 42 is arranged at the connection of one first connecting piece 41 and the upper chord member 1, and the other end is arranged at the connection of the adjacent other first connecting piece 41 and the lower chord member 1. By arranging the first connecting pieces 41 to be connected orthogonally to the upper string member 1 and the lower string member 1, respectively, the first connecting pieces 41 provide the string member 1 with a supporting force in the vertical direction. The second connecting member 22 is disposed obliquely, and provides an oblique supporting force for the chord member 1, so as to further improve the supporting strength of the supporting member 100 to the enclosure 200.

Further, in an embodiment, referring to fig. 1, the present application provides a supporting member 100 in which two adjacent second connecting members 42 are symmetrically disposed with respect to the first connecting member 41. Thus, at the connection of the first connecting member 41 and the two second connecting members 42 at the upper chord member 1 and the lower chord member 1, respectively, a three-point support is formed, and the two adjacent second connecting members 42 apply symmetrical forces to the upper chord member 1 or to the lower chord member 1, thereby facilitating the support member 100 to be in a stable balanced state.

In an embodiment, in the supporting member 100 provided by the present application, in order to ensure the strength of the supporting member 100 itself and prevent the supporting member 100 from failing to support the enclosure 200, the distance between two adjacent first connectors 41 is 1m to 3m, for example, may be 1m, 1.5m, 1.8m, 2m, 2.4m, 2.7m, or 3m, etc., so as to avoid that the interval between the first connectors 41 is too long, and the strength of the supporting member 100 is low, so that it is not enough to effectively support the enclosure 200.

In an embodiment, referring to fig. 1, the present application provides a support member 100, in which an upper middle chord 11, a lower middle chord 11 and at least one first connecting member 41 form a middle splicing unit 21. Specifically, the intermediate splicing unit 21 may include one first connecting member 41, or may include 2 or more first connecting members 41, so as to select the actual construction requirement. In the field construction, the intermediate splice unit 21 may be spliced as a whole. Therefore, the prefabricated middle splicing units 21 can be spliced well before construction, and the time of site construction is further shortened.

In one embodiment, referring to fig. 1, the present application provides a support member 100, in which an upper end chord 12, a lower end chord 12 and at least one first connecting member 41 form an end splicing unit 22. Like the middle splicing unit 21, the end splicing units 22 can be spliced well before construction, so that the field is prevented from being spliced one by one, the construction difficulty is reduced, and the field construction time is saved.

It can be understood that, when the middle splicing units 21 and the end splicing units 22 are adopted simultaneously, in the process of field construction, the assembling work of the field supporting member 100 can be completed only by splicing a plurality of middle splicing units 21 between the two end splicing units 22, so that the assembling and disassembling time of the field supporting member 100 is greatly reduced.

It should be noted that the intermediate splicing unit 21 may be formed by respectively casting concrete on the intermediate chord 11 and the first connecting member 41, and then connecting them together by the connecting member to form the intermediate splicing unit 21, or may be integrally formed in the casting process of concrete. Similarly, the end splicing unit 22 can be formed by respectively pouring concrete on the end chord 12 and the first connecting piece 41, and then connected together by the connecting piece to form the end splicing unit 22, or can be integrally formed in the concrete pouring process.

In an embodiment, referring to fig. 1, in the supporting member 100 provided by the present application, the connecting member 4 further includes third connecting members 43, and the two third connecting members 43 are symmetrically disposed at the middle portion of the supporting member 100. One end of each third connecting piece 43 is arranged in the middle of the upper chord member 1, and the other end is arranged at the connection of the adjacent first connecting piece 41 and the lower chord member 1. It will be appreciated that the two third connecting members 43 form a three-point support in cooperation with one first connecting member, compared to the two-point support of the first connecting member 41 and the second connecting member 42, which can provide a stronger supporting strength to the supporting member 100. When the support member 100 supports the enclosure 200 at both ends thereof, the middle portion of the support member 100 may be subjected to a large bending stress, and by providing two third connection members 43 and a first connection member at the middle portion of the support member 100, the structural strength of the middle portion may be improved, and the support member 100 may be prevented from being deformed or broken.

Alternatively, in an embodiment not shown, the present application provides a support member 100 in which one end of each third connecting member 43 is disposed at the middle of the lower chord member 1 and the other end is disposed at the junction of the adjacent first connecting member 41 and the upper chord member 1. In this embodiment and the previous embodiment, the technical solution in which one end of the third connecting member is disposed in the middle of the upper chord member 1 has the same technical effect, and is not described herein again.

A second aspect of an embodiment of the present application provides an excavation supporting system, please refer to fig. 1. The foundation pit supporting system comprises the enclosure 200 and the supporting member 100 provided by any one of the above embodiments, and a foundation pit is formed by digging in the enclosure 200. A plurality of support members 100 are spaced apart on the enclosure 200 above the foundation pit.

The foundation pit supporting system provided by the embodiment of the application has the same technical effects due to the adoption of the supporting member 100 provided by any one of the above embodiments, and the details are not repeated herein.

Further, in an embodiment, referring to fig. 1, in the foundation pit supporting system provided by the present application, the enclosure body 200 includes an enclosure wall 210, a crown beam 220 and a retaining wall 230. A foundation pit is formed by digging in the enclosure wall 210, the crown beam 220 is connected to the top end of the enclosure wall 210, and the retaining wall 230 is connected to the upper part of the crown beam 220. The upper chord member 1 is detachably attached to the crown beam 220, and the lower chord member 1 is attached to the enclosure wall 210. It will be appreciated that since the upper chord member 1 is to be removed after the bracing work is completed, it is necessary to provide the detachable connection between the chord member 1 and the enclosure 200, and by connecting the upper chord member 1 to the crown beam 220, it is convenient not only to connect the upper chord member 1 to the enclosure 200 but also to remove it. The lower chord member 1 needs to be retained to provide support for the station roof 410, so that the lower chord member 1 can be permanently connected with the enclosure 200, and the more firmly the connection is, the higher the support reliability is.

It can be understood that the connection form of the chord member 1 at the upper part and the crown beam 220 and the connection form of the chord member 1 at the lower part and the enclosure wall 210 can be through flange connection, or the connection can be pre-buried on the enclosure wall 210 and the crown beam 220 and connected through pre-buried connection members. The chord member 1 at the lower part and the enclosure wall 210 can be connected permanently, so the connection of the chord member and the enclosure wall can be in the form of pouring concrete at the connection part of the chord member and the enclosure wall, and can also be welded.

In a preferred embodiment, referring to fig. 1, in the foundation pit supporting system provided by the present application, the top beam 220 has a first pre-buried connector 221, and the upper chord member 1 is detachably connected to the top beam 220 through the first pre-buried connector 221. Specifically, the first pre-embedded connection member 221 may be a pre-embedded anchor bolt or a bolt, and the upper chord member 1 should have a fitting hole matched with the first pre-embedded connection member. Through the first pre-buried connecting piece 221, not only is the connecting strength between the upper chord member 1 and the crown beam 220 improved, but also the convenience of connection between the upper chord member and the crown beam is improved.

In an embodiment, referring to fig. 1, in the foundation pit supporting system provided by the present application, the enclosure wall 210 has a second pre-embedded connector 211, and the chord member 1 at the lower portion is connected to the enclosure wall 210 through the second pre-embedded connector 211. Specifically, the first fastener driving member 221 may be a fastener bolt or a bolt, and the lower chord member 2 should have a fitting hole for fitting. In addition, the lower chord member 2 and the enclosure wall 210 can be permanently connected, or steel members can be embedded at the matching position of the lower chord member and the enclosure wall, and the lower chord member and the enclosure wall are connected in a welding mode.

In one embodiment, referring to fig. 1, the foundation pit supporting system provided by the present application further includes a supporting body 300 located in the foundation pit. The supporting body 300 is coupled at both ends thereof to the two opposite walls of the enclosure 200. It can be understood that as the excavation depth of the excavation increases, it is not sufficient to provide support to the enclosure 200 by means of the support members 100 alone, and it is necessary to continuously install the supports 300 on the walls at both ends of the enclosure 200 to provide effective support to the enclosure 200. According to the difference of the depth of the foundation pit and the difference of the distance between the two opposite walls of the enclosure 200 in the foundation pit, the supporting force required by the enclosure 200 is different, so that a proper number of supporting bodies 300 can be arranged according to the requirements of site construction.

In an embodiment, in the foundation pit supporting system provided by the present application, the supporting body 300 is made of steel, and it can be understood that the steel has high bending strength and can be recycled, so that not only can the supporting requirement be met, but also the resource utilization rate can be improved.

It should be noted that, in the process of sequentially building the station bottom plate 430, the station middle plate 420 and the station top plate 410 from bottom to top in the subway station, the support bodies 300 need to be removed one by one in due time, so that the support bodies 300 provide support for the enclosure body 200 and do not affect the construction work of the subway station.

A third aspect of the embodiments of the present application provides a construction method for a subway station, please refer to fig. 3, where with the adoption of the foundation pit supporting system provided in any one of the above embodiments, the construction method includes:

s1, constructing an enclosure body 200 of a foundation pit supporting system;

s2, excavating a foundation pit in the enclosure 200 to a preset first depth;

s3, mounting the supporting member 100 on the enclosure 200;

s4, excavating the foundation pit to a preset second depth;

s5, constructing a main body frame of the station, and leaving a blank station top plate 410;

s6, removing the main body frame of the support member 100 and reserving the chord member 1 at the lower part of the support member 100;

and S7, constructing and forming the station roof 410 at the position of the chord member 1 at the lower part.

The construction method of the subway station provided by the embodiment of the application has the same technical effect due to the adoption of the foundation pit supporting system provided by any one of the above embodiments, and is not repeated herein.

It should be noted that, in the process of excavating the foundation pit, the support member 100 needs to be installed between the walls of the enclosure 200, and the preset first depth in step S2 is the depth at which the support member 100 can be constructed, which is determined according to the preset installation position of the support member 100. And continuously excavating the foundation pit, wherein in the process of excavating the foundation pit, the support body 300 is required to be installed at a corresponding depth according to the bearing capacity of the enclosure body 200 and the width of the foundation pit.

According to the position of the designed station bottom plate 430, when digging the second preset depth, namely when the station bottom plate 430 is to be constructed, the main frame of the station is not dug downwards any more, and the construction is started, wherein the main frame comprises the station bottom plate 430, a station wall body, a station upright post and a station middle plate 420. It is understood that the support body 300 should be sequentially removed from the bottom up in the process of constructing the main body frame of the station from the bottom up.

The various embodiments/implementations provided herein may be combined with each other without contradiction.

The above description is only a preferred embodiment of the present application and is not intended to limit the present application, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, improvement and the like made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A supporting member for use in a foundation pit support system for constructing a subway station, the supporting member comprising:

the two chord members are arranged at intervals up and down, two ends of each chord member are respectively connected to the enclosure of the foundation pit supporting system, and two ends of at least the upper chord member are detachably connected with the enclosure; and

and the connecting piece is connected between the upper chord piece and the lower chord piece.

2. The support member of claim 1,

the chord member comprises a plurality of spliced middle chords and end chords which are respectively spliced at two ends of the middle chords;

and the adjacent middle chords and the end chords and the middle chords are connected through flange structures.

3. The support member of claim 2, wherein the connector comprises:

the two ends of the first connecting piece are respectively orthogonally connected with the chord member bar at the upper part and the chord member bar at the lower part; and

and one end of the second connecting piece is arranged at the joint of one first connecting piece and the chord member at the upper part, and the other end of the second connecting piece is arranged at the joint of the other adjacent first connecting piece and the chord member at the lower part.

4. The support member according to claim 3, wherein adjacent two of the second connectors are symmetrically disposed with respect to the first connector; and/or the presence of a gas in the gas,

the distance between two adjacent first connecting pieces is 1-3 m.

5. The support structure of claim 3, wherein an upper one of said intermediate chords, a lower one of said intermediate chords, and at least one of said first connectors comprise an intermediate splice unit; and/or the presence of a gas in the gas,

one end part chord member on the upper part, one end part chord member on the lower part and at least one first connecting piece form an end part splicing unit.

6. The support structure according to claim 3, wherein the connectors further comprise third connectors, and the third connectors are symmetrically arranged in the middle of the support structure;

one end of each third connecting piece is arranged in the middle of the chord member at the upper part, and the other end of each third connecting piece is arranged at the connecting part of the adjacent first connecting piece and the chord member at the lower part; or the like, or, alternatively,

one end of each third connecting piece is arranged in the middle of the chord member at the lower part, and the other end of each third connecting piece is arranged at the joint of the adjacent first connecting piece and the chord member at the upper part.

7. An excavation supporting system, comprising:

the enclosure body is internally excavated to form a foundation pit; and

the support member of any one of claims 1 to 6, wherein a plurality of the support members are spaced apart from one another on the enclosure above the excavation.

8. The system as claimed in claim 7, wherein the enclosure includes an enclosure wall, a crown beam and a retaining wall, the enclosure wall is excavated to form the pit, the crown beam is connected to a top end of the enclosure wall, and the retaining wall is connected to an upper portion of the crown beam;

the chord member on the upper part is detachably connected to the crown beam, and the chord member on the lower part is connected to the enclosure wall.

9. The excavation supporting system of claim 8, wherein the crown beam has a first pre-embedded connector thereon, and the upper chord member is detachably connected to the crown beam through the first pre-embedded connector.

10. The foundation pit supporting system according to any one of claims 7 to 9, further comprising a supporting body located in the foundation pit, wherein two ends of the supporting body are connected to two walls opposite to the enclosure.