A semi-underground subway station buoyancy compensation system and method

Abstract

The present application relates to the field of track construction, and relates to a semi-underground subway station buoyancy compensation system and method, the compensation system comprising a retaining structure, a newly-built station, a crown beam and a connecting beam, the retaining structure being provided with an existing station; the newly-built station comprising a first station structure and a second station structure, the first station structure and the second station structure being arranged on the two sides of the existing station, the retaining structure being arranged between the first station structure and the existing station; the crown beam being arranged on the top of the retaining structure, the crown beam being fixedly connected with the retaining structure; the connecting beam being arranged between the existing station and the crown beam, one end of the connecting beam being fixedly connected with the crown beam, and the other end of the connecting beam being fixedly connected with the existing station, the present application solves the problems of high construction risk, long period and high cost of the semi-underground subway station buoyancy compensation measures, and simultaneously solves the core problem of insufficient resistance to buoyancy after the newly-built line passes through the existing station.

Description

Technical Field

[0001] This invention relates to the field of rail transit technology, and more specifically, to a buoyancy compensation system and method for a semi-underground subway station. Background Technology

[0002] With the rapid development of underground rail transit and the increasing number of newly constructed subway lines, there are situations where new subway lines need to cross or pass under existing operating stations. Early construction lines, due to the lack of relevant crossing conditions, frequently encounter situations where they pass under the anti-buoyancy piles of existing stations during construction, further making it difficult to meet the anti-buoyancy requirements of existing stations.

[0003] For projects where new stations intersect with existing stations, conventional compensation measures involve installing anti-uplift piles or using pile foundation replacement around the existing station's foundation slab. However, these measures can only be implemented in the water-rich underground layer of the existing station, resulting in extremely high construction risks. Furthermore, the construction period for adding anti-uplift piles is long and the cost is high. Summary of the Invention

[0004] The purpose of this invention is to provide a buoyancy compensation system and method for semi-underground subway stations to improve the aforementioned problems. To achieve this objective, the technical solution adopted by this invention is as follows:

[0005] On one hand, this application provides a buoyancy compensation system for a semi-underground subway station. The compensation system includes an enclosure structure, a newly built station, a capping beam, and a connecting beam. An existing station is located within the enclosure structure. The newly built station includes a first station structure and a second station structure, which are located on both sides of the existing station. The enclosure structure is located between the first station structure and the existing station. The capping beam is located on top of the enclosure structure and is fixedly connected to the enclosure structure. The connecting beam is located between the existing station and the capping beam, with one end of the connecting beam fixedly connected to the capping beam and the other end of the connecting beam fixedly connected to the existing station.

[0006] On the other hand, this application provides a buoyancy compensation method for a semi-underground subway station, the method comprising:

[0007] Obtain the connection beam layout plan and geological survey report;

[0008] The pull-out coefficient and the standard value of the ultimate skin friction of the pile side are determined based on the geological survey report.

[0009] Obtain the number of anti-buoyancy piles cut off during construction;

[0010] The weakening buoyancy information is obtained by calculating based on the pull-out coefficient, the standard value of the ultimate skin friction of the pile side, and the number of anti-buoyancy piles cut off during construction.

[0011] The number of rebars required for the connecting beam is calculated based on the information about reduced buoyancy.

[0012] The connecting beams are set up based on the aforementioned connecting beam layout scheme and the number of rebars installed in the connecting beams.

[0013] The beneficial effects of this invention are:

[0014] This invention, through buoyancy compensation construction of semi-underground subway stations, transfers the high-risk construction of the lower part of the operating station to a controllable upper area, reducing construction risks and eliminating the need to interrupt the operation of existing stations. Compared with traditional anti-buoyancy technology, it adds connecting beams to the temporary retaining structure of the new line and fixes them to the middle plate of the existing station, forming an anti-buoyancy system that transforms the temporary structure into a permanent structure, reducing redundant construction and space waste, and further shortening the construction cycle and reducing construction costs.

[0015] Other features and advantages of the invention will be set forth in the following description, and will be apparent in part from the description, or may be learned by practicing embodiments of the invention. The objects and other advantages of the invention may be realized and obtained by means of the structures particularly pointed out in the written description, claims, and drawings. Attached Figure Description

[0016] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a schematic diagram of the buoyancy compensation system for a semi-underground subway station as described in an embodiment of the present invention.

[0018] Figure 2 This is a top view of the semi-underground subway station buoyancy compensation system described in this embodiment of the invention.

[0019] Figure 3 This is a schematic diagram of the waterproof structure of the semi-underground subway station buoyancy compensation system described in this embodiment of the invention.

[0020] Figure 4 This is a schematic diagram showing the horn structure described in this embodiment of the invention positioned below the connecting beam.

[0021] Figure 5 This is a schematic diagram of the rebar installation method for the connecting beam described in an embodiment of the present invention.

[0022] Marked in the diagram: 1. Base plate; 2. Middle plate; 3. Side wall; 4. Superstructure; 5. Enclosure structure; 6. Crown beam; 7. Connecting beam; 8. Horn structure; 9. Anti-buoyancy pile; 10. New underpass section; 11. First station structure; 12. Second station structure; 13. Waterproof layer; 14. Grouting pipe. Detailed Implementation

[0023] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0024] It should be noted that similar reference numerals and letters in the following figures indicate similar items; therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures. Furthermore, in the description of this invention, terms such as "first," "second," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0025] Example 1

[0026] like Figure 1 and Figure 2 As shown, this embodiment provides a buoyancy compensation system for a semi-underground subway station. The compensation system includes a retaining structure 5, a newly built station, a capping beam 6, and a connecting beam 7. An existing station is located within the retaining structure 5. The newly built station includes a first station structure 11 and a second station structure 12, which are located on both sides of the existing station. The retaining structure 5 is located between the first station structure 11 and the existing station. The capping beam 6 is located on top of the retaining structure 5 and is fixedly connected to the retaining structure 5. The connecting beam 7 is located between the existing station and the capping beam 6. One end of the connecting beam 7 is fixedly connected to the capping beam 6, and the other end of the connecting beam 7 is fixedly connected to the existing station. By adding a connecting beam 7 to the capping beam 6 of the retaining structure 5 of the newly built station, the connecting beam 7 is rigidly connected to the existing station, transforming the temporary retaining structure 5 into a permanent anti-buoyancy structure. This reduces the waste caused by repeated construction, meets the anti-buoyancy requirements of the existing station, and solves the problem of interference with the existing station during construction.

[0027] In one specific embodiment of this disclosure, the existing station includes a superstructure 4, a middle slab 2, side walls 3, and a bottom slab 1. The middle slab 2 is located between the superstructure 4 and the bottom slab 1. The superstructure 4 and the middle slab 2 are fixedly connected through the side walls 3, and the bottom slab 1 and the middle slab 2 are fixedly connected through the side walls 3. The superstructure 4 is located above the soil, while the middle slab 2, side walls 3, and bottom slab 1 are all located in the soil. The height of the bottom slab 1 is greater than the height of the newly constructed underpass section 10. The existing station is a semi-underground subway station structure. By placing the newly constructed underpass section 10 below the existing station, the interference with existing operations during construction is reduced. Buoyancy compensation measures are concentrated in the superstructure 4 to avoid collapse and water leakage during construction, which would seriously affect the construction environment.

[0028] In one specific embodiment of this disclosure, a bull horn structure 8 is provided on the side wall 3. The bull horn structure 8 is located on one side of the location of the newly built station and is located at the end of the middle plate 2.

[0029] In one specific embodiment of this disclosure, the horn structure 8 is set above the connecting beam 7. One end of the connecting beam 7 is fixedly connected to the side wall 3, and the other end of the connecting beam 7 is fixedly connected to the cap beam 6. By utilizing the cap beam on the newly built enclosure structure and the construction of the upper area of ​​the existing station, the construction operation space is transferred from the high-risk lower part of the operating station to the controllable upper area, thereby reducing the construction risk.

[0030] like Figure 4 As shown, in one specific embodiment of this disclosure, the horn structure 8 is set below the connecting beam 7, the bottom of the connecting beam 7 contacts the top of the horn structure 8, one end of the connecting beam 7 is fixedly connected to the upper structure 4, and the other end of the connecting beam 7 is fixedly connected to the crown beam 6. By placing the connecting beam on the existing station slab, and filling the bottom of the connecting beam and the horn structure with 120mm thick C40 micro-expansion concrete for anti-buoyancy force transmission, this structure achieves the anti-buoyancy compensation requirement without damaging the existing station waterproofing. It should be noted that the design method of the horn structure 8 can be selected according to the specific construction scenario.

[0031] In one specific embodiment of this disclosure, the connecting beam 7 is laid along the length of the cap beam 6, and two adjacent connecting beams 7 are spaced apart. By arranging the connecting beams 7 at intervals, the anti-buoyancy structure can adapt to deformation cracks caused by temperature and settlement, while the local anti-buoyancy force is evenly transferred to the entire bottom plate 1, avoiding stress concentration and structural damage to the existing station, ensuring anti-buoyancy stability, and the spaced arrangement construction method is more convenient for construction, achieving the effect of saving time and increasing efficiency.

[0032] like Figure 3As shown in a specific embodiment of this disclosure, a waterproof structure is provided at the connection between the connecting beam 7 and the existing station. The waterproof structure includes a waterproof layer 13 and a grouting pipe 14. The waterproof layer 13 is L-shaped, with one end of the waterproof layer 13 in contact with the existing station and the other end of the waterproof layer 13 in contact with the connecting beam 7. The grouting pipe 14 is located inside the connecting beam 7, with one end of the grouting pipe 14 penetrating the surface of the connecting beam 7 and the other end of the grouting pipe 14 located at the connection between the connecting beam 7 and the existing station. By laying two layers of waterproof layer 13 on the water-facing side of the anti-buoyancy node, namely a 3mm thick self-adhesive polymer-modified bitumen waterproof membrane and a 4mm thick polymer-modified bitumen waterproof membrane, and setting one grouting pipe 14 in each section of the connecting beam 7, grouting is performed using the grouting pipe 14 to fill the gaps within the range of the two sealant layers, thereby achieving the purpose of water stoppage. This meets the waterproof performance requirements of the key anti-buoyancy connection point, protects the structural safety of the existing station operation, and reduces the later maintenance costs.

[0033] Example 2

[0034] This embodiment provides a buoyancy compensation method for a semi-underground subway station, the method comprising:

[0035] Step S1: Obtain the layout plan and geological survey report for the connecting beam 7.

[0036] Step S2: Determine the pull-out coefficient and the standard value of the ultimate skin friction of the pile based on the geological survey report;

[0037] In this step, the pull-out coefficient is determined by the type and state of the soil and needs to be determined by referring to the specifications. For example, it is 0.7 to 0.8 for cohesive soil and 0.5 to 0.7 for sandy soil.

[0038] Step S3: Obtain the number of anti-buoyancy piles 9 that were cut off during the construction process.

[0039] Step S4: Calculate the weakened buoyancy information based on the pull-out coefficient, the standard value of the ultimate skin friction of the pile side, and the number of anti-buoyancy piles 9 cut off during construction.

[0040] Step S4 further includes steps S41, S42, S43, and S44, which specifically include:

[0041] Step S41: Obtain the design parameters of the anti-buoyancy pile 9;

[0042] Step S42: Determine the type information of the anti-buoyancy pile 9 according to the design parameters of the anti-buoyancy pile 9;

[0043] Step S43: Determine the perimeter of the anti-buoyancy pile 9 based on the type information of the anti-buoyancy pile 9, and obtain the perimeter information;

[0044] In this step, if the cross-section of the anti-buoyancy pile is circular and the circumference is u...p =πd, where d is the diameter. If the cross-section of the anti-buoyancy pile is square, the perimeter is calculated based on the actual perimeter.

[0045] Step S44: Calculate the weakened buoyancy information based on the perimeter information, the pull-out coefficient, the standard value of the ultimate skin friction of the pile side, the effective embedment depth of the anti-buoyancy pile 9, and the number of anti-buoyancy piles 9 cut off during construction.

[0046] In this step, the formula for calculating the weakened buoyancy information is as follows:

[0047] R k =n∑λ i ·q sik ·u p ·l i

[0048] Where n is the number of anti-buoyancy piles cut off by the newly constructed underpass section 10; λ i q is the pull-out coefficient of the i-th soil layer; sik Let u be the standard value of the ultimate skin friction resistance of the i-th soil layer on the pile side; p The circumference of the pile body; l i The length of the pile shaft penetrating the i-th soil layer is the effective embedment depth of the pile in that soil layer.

[0049] Step S5: Calculate the number of rebars for the connecting beam 7 based on the weakened buoyancy information.

[0050] Step S5 further includes steps S51, S52, S53, S54, S55, and S56, which specifically include:

[0051] Step S51: Obtain the diameter parameters and material parameters of the reinforcing bars;

[0052] Step S52: Calculate the area information of the shear surface of the steel bar based on the diameter parameter of the steel bar;

[0053] In this step, the specific formula for calculating the area of ​​the shear surface of a single rebar is as follows:

[0054]

[0055] Among them, A s0 d0 is the area of ​​the shear surface of a single steel bar; d0 is the diameter of the steel bar.

[0056] Step S53: Determine the design value of the shear strength of the reinforcing steel based on the material parameter information of the reinforcing steel.

[0057] Step S54: Calculate based on the area information of the shear surface of the steel bar and the design value of the shear strength of the steel bar to obtain the first calculation result;

[0058] In this step, the first calculation result is the product of the area of ​​the shear surface of the single steel bar and the design value of the shear strength of the steel bar.

[0059] Step S55: Calculate based on the first calculation result and the weakened anti-buoyancy information to obtain the second calculation result;

[0060] In this step, the second calculation result is the ratio of the weakened anti-buoyancy information to the first calculation result.

[0061] Step S56: Determine the number of reinforcing bars for the connecting beam 7 based on the second calculation result;

[0062] In this step, such as Figure 5 As shown, the internal reinforcement of connecting beam 7 is composed of intersecting transverse and longitudinal reinforcement. The number of rebars refers to the number of transverse reinforcements embedded in the existing station structure. The specific formula for calculating the number of rebars within the range of a single connecting beam is as follows:

[0063] n0·A s0 ·f v ≥V s =R k

[0064] Transforming the above formula, we get:

[0065] n0≥R k / (A s0 f v )

[0066] Among them, R k To weaken the anti-buoyancy force; A s0 f is the area of ​​the shear surface of a single steel bar; v This is the design value for the shear strength of the reinforcing steel.

[0067] Step S6: Based on the layout scheme of the connecting beam 7 and the number of rebars in the connecting beam 7, set up the connecting beam 7.

[0068] Because the newly constructed underpass 10 damages the anti-buoyancy piles 9 of the existing stations, the anti-buoyancy requirements of the existing stations are difficult to meet. Existing technologies usually meet the anti-buoyancy requirements by adding anti-buoyancy piles 9 around the existing stations. However, this repeated construction increases the construction cycle and wastes construction materials. This application adds a connecting beam 7, allowing the newly constructed temporary structure to participate in the anti-buoyancy system. According to relevant calculations, a reasonable number of steel bars are planted on the connecting beam 7, so that the anti-buoyancy system can achieve stable performance requirements, meet the anti-buoyancy requirements, and greatly reduce the cost of materials.

[0069] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of this invention is in use. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention. In addition, the terms "first," "second," "third," etc., are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0070] In the description of this invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0071] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

[0072] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A buoyancy compensation method for a semi-underground subway station, comprising a buoyancy compensation system for a semi-underground subway station, characterized in that, The buoyancy compensation system of the semi-underground subway station includes: an enclosure structure (5), in which an existing station is located; The newly built station includes a first station structure (11) and a second station structure (12), the first station structure (11) and the second station structure (12) are located on both sides of the existing station, and the enclosure structure (5) is located between the first station structure (11) and the existing station. Crown beam (6), the crown beam (6) is disposed on the top of the enclosure structure (5), and the crown beam (6) is fixedly connected to the enclosure structure (5); A connecting beam (7) is provided between the existing station and the capping beam (6). One end of the connecting beam (7) is fixedly connected to the capping beam (6), and the other end of the connecting beam (7) is fixedly connected to the existing station. The buoyancy compensation method for the semi-underground subway station includes the following steps: Obtain the layout plan and geological survey report of the connecting beam (7). The layout plan of the connecting beam indicates that the connecting beams are arranged at intervals along the length of the cap beam. One end of the connecting beam is fixedly connected to the existing station side wall, and the other end of the connecting beam is fixedly connected to the cap beam. The pull-out coefficient and the standard value of the ultimate skin friction of the pile side are determined based on the geological survey report. Obtain the number of anti-buoyancy piles (9) that were cut off during construction; The weakening buoyancy information is obtained by calculating based on the pull-out coefficient, the standard value of the ultimate skin friction of the pile side and the number of anti-buoyancy piles (9) cut off during the construction process; The number of reinforcing bars for the connecting beam (7) is calculated based on the weakened buoyancy information. The connecting beam (7) is set up based on the layout scheme of the connecting beam (7) and the number of rebars in the connecting beam (7); The calculation is based on the pull-out coefficient, the standard value of the ultimate skin friction of the pile side, and the number of anti-buoyancy piles (9) cut off during construction, including: Obtain the design parameters of the anti-buoyancy pile (9); The type information of the anti-buoyancy pile (9) is determined according to the design parameters of the anti-buoyancy pile (9); The perimeter of the anti-buoyancy pile (9) is determined based on the type information of the anti-buoyancy pile (9), and the perimeter information is obtained; The weakened buoyancy information is obtained by calculating based on the perimeter information, the pull-out coefficient, the standard value of the ultimate skin friction of the pile side, and the number of anti-buoyancy piles (9) cut off during the construction process; The number of rebars for the connecting beam (7) is calculated based on the weakened buoyancy information, including: Obtain the diameter and material parameters of the reinforcing bars; The area information of the shear surface of the steel bar is obtained by calculating based on the diameter parameter of the steel bar. The design value of the shear strength of the reinforcing steel is determined based on the material parameter information of the reinforcing steel. The first calculation result is obtained by calculating the area of ​​the shear surface of a single steel bar and the design value of the shear strength of the steel bar. A second calculation result is obtained by calculating based on the first calculation result and the weakened anti-buoyancy information. The second calculation result is the ratio of the weakened anti-buoyancy information to the first calculation result. The number of reinforcing bars for the connecting beam (7) is determined based on the second calculation result.

2. A buoyancy compensation system for a semi-underground subway station, used in the buoyancy compensation method for a semi-underground subway station as described in claim 1, characterized in that, include: Enclosure structure (5), within which an existing station is located; The newly built station includes a first station structure (11) and a second station structure (12), the first station structure (11) and the second station structure (12) are located on both sides of the existing station, and the enclosure structure (5) is located between the first station structure (11) and the existing station. Crown beam (6), the crown beam (6) is disposed on the top of the enclosure structure (5), and the crown beam (6) is fixedly connected to the enclosure structure (5); A connecting beam (7) is provided between the existing station and the capping beam (6). One end of the connecting beam (7) is fixedly connected to the capping beam (6), and the other end of the connecting beam (7) is fixedly connected to the existing station.

3. The buoyancy compensation system for a semi-underground subway station according to claim 2, characterized in that, The existing station includes an upper structure (4), a middle slab (2), side walls (3), and a bottom slab (1). The middle slab (2) is located between the upper structure (4) and the bottom slab (1). The upper structure (4) and the middle slab (2) are fixedly connected through the side walls (3). The bottom slab (1) and the middle slab (2) are fixedly connected through the side walls (3). The upper structure (4) is located above the soil. The middle slab (2), the side walls (3), and the bottom slab (1) are all located in the soil. The height of the bottom slab (1) is greater than the height of the newly built underpass section (10).

4. The buoyancy compensation system for a semi-underground subway station according to claim 3, characterized in that, A bull horn structure (8) is provided on the side wall (3). The bull horn structure (8) is located on one side of the location of the newly built station. The bull horn structure (8) is located at the end of the middle plate (2).

5. The buoyancy compensation system for a semi-underground subway station according to claim 4, characterized in that, The horn structure (8) is located above the connecting beam (7), one end of the connecting beam (7) is fixedly connected to the side wall (3), and the other end of the connecting beam (7) is fixedly connected to the crown beam (6).

6. The buoyancy compensation system for a semi-underground subway station according to claim 4, characterized in that, The horn structure (8) is located below the connecting beam (7), the bottom of the connecting beam (7) is in contact with the top of the horn structure (8), one end of the connecting beam (7) is fixedly connected to the upper structure (4), and the other end of the connecting beam (7) is fixedly connected to the crown beam (6).

7. The buoyancy compensation system for a semi-underground subway station according to claim 2, characterized in that, The connecting beam (7) is laid along the length of the cap beam (6), and two adjacent connecting beams (7) are spaced apart.

8. The buoyancy compensation system for a semi-underground subway station according to claim 2, characterized in that, A waterproof structure is provided at the connection between the connecting beam (7) and the existing station. The waterproof structure includes a waterproof layer (13) and a grouting pipe (14). The waterproof layer (13) is L-shaped. One end of the waterproof layer (13) contacts the existing station, and the other end of the waterproof layer (13) contacts the connecting beam (7). The grouting pipe (14) is located inside the connecting beam (7). One end of the grouting pipe (14) penetrates the surface of the connecting beam (7), and the other end of the grouting pipe (14) is located at the connection between the connecting beam (7) and the existing station.

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