Ventilation structure of metro interval tunnel and construction method of ventilation structure

Abstract

The invention relates to the technical field of subway tunnel construction, in particular to a ventilation structure of a subway interval tunnel and a construction method of the ventilation structure. The ventilation structure comprises a vertical shaft, a left line tunnel, a right line tunnel, a first transverse hole and a second transverse hole, wherein the left line tunnel and the right line tunnel are arranged in parallel; the first transverse hole is connected and communicated with the left line tunnel and the right line tunnel; the second transverse hole is connected and communicated with the left line tunnel and the right line tunnel; the vertical shaft is communicated with the first transverse hole; an equipment well is excavated in the top position of the vertical shaft, and an opening of the vertical shaft is located on the bottom wall of the equipment well; the equipment well is communicated with the second transverse hole through a parallel pilot tunnel; the vertical shaft is formed by expanding and excavating an existing construction vertical shaft; the first transverse hole and the second transverse hole are formed by expanding excavation of existing construction transverse holes. The existing construction vertical shaft and the existing construction transverse hole are effectively utilized, the purposes of practicability and saving are achieved, and the construction cost is reduced.

Description

Technical Field

[0001] The invention relates to the technical field of subway tunnel construction, and in particular to a ventilation structure of a subway section tunnel and a construction method thereof. Background Art

[0002] Large and medium-sized cities are the main areas of urban population concentration. In order to alleviate the heavy traffic pressure in urban areas, improve the efficiency of citizens' attendance, and enhance the radiation and driving effect of urban economy, they have chosen to layout or intensify urban rail transit planning.

[0003] Urban rail transit is mainly composed of interval tunnels, supplemented by bridges. During the operation period, the train operation density is high, and a large amount of harmful gases and heat will accumulate in the tunnel. Therefore, when the subway interval tunnel is long, interval air shafts must be set up to ventilate the tunnel, introduce fresh air into the tunnel, and discharge harmful gases and heat from the tunnel to improve the air environment in the tunnel.

[0004] The location of the interval ventilation shaft must meet the ventilation needs of the interval tunnel operation and the emergency evacuation function. It is generally located near the midpoint of the interval tunnel, and in most cases overlaps with the location of the construction shaft. However, during the current construction of subway interval tunnels, multiple temporary construction shafts are set up as construction passages to increase the tunnel excavation working surface. After the construction is completed, the construction shafts are generally abandoned and backfilled, resulting in great waste. Therefore, the construction shafts can be fully utilized for transformation and upgrading to meet the ventilation needs of the interval ventilation shafts and serve as evacuation passages. How to utilize the existing construction shafts for transformation and upgrading to meet the ventilation needs of the interval ventilation shafts and serve as evacuation passages is a technical problem that needs to be solved urgently. Summary of the invention

[0005] The main purpose of the present invention is to propose a ventilation structure for a subway section tunnel and a construction method thereof, aiming to solve the above-mentioned technical problems.

[0006] To achieve the above-mentioned purpose, on the one hand, the present invention proposes a ventilation structure for a subway section tunnel, comprising a vertical shaft and a left-line tunnel and a right-line tunnel arranged in parallel with each other, and also comprising a first horizontal tunnel and a second horizontal tunnel arranged at intervals from each other; the first horizontal tunnel is connected and penetrated with the left-line tunnel and the right-line tunnel; the second horizontal tunnel is connected and penetrated with the left-line tunnel and the right-line tunnel; the vertical shaft is connected with the first horizontal tunnel; an equipment shaft is excavated at the top position of the vertical shaft, and the mouth of the vertical shaft is located on the bottom wall of the equipment shaft; the equipment shaft and the second horizontal tunnel are connected through a parallel guide pit; the vertical shaft is formed by expanding and excavating the existing construction vertical shaft; the first horizontal tunnel and the second horizontal tunnel are respectively formed by expanding and excavating the existing construction horizontal tunnels.

[0007] Preferably, the parallel guide pit is located outside the left-line tunnel or the right-line tunnel, and in a top-down direction, the parallel guide pit is parallel to the left-line tunnel or the right-line tunnel.

[0008] Preferably, the parallel guide pit gradually rises from the second transverse hole position to the equipment well, so that the parallel guide pit has a slope.

[0009] Preferably, the upper structure of the cross-section of the first transverse tunnel and the second transverse tunnel is a semicircular arch, and the lower structure is a rectangle; the connection part between the first transverse tunnel, the second transverse tunnel and the left-line tunnel and the right-line tunnel is located in the lower rectangular part, and the connection part between the second transverse tunnel and the parallel guide pit is located in the upper semicircular arch part.

[0010] On the other hand, the present invention also provides a construction method for the ventilation structure of the above-mentioned subway section tunnel, comprising the following steps:

[0011] S1. Expand and dig two adjacent existing construction transverse tunnels to obtain a first transverse tunnel and a second transverse tunnel;

[0012] S2. Backfill the existing construction shaft: pour a concrete retaining wall at the connection between the existing construction shaft and the first horizontal hole, and then use slag to backfill the existing construction shaft to the ground level;

[0013] S3. Digging equipment wells;

[0014] S4. After the equipment well is excavated to the designed elevation, a parallel pilot pit is excavated between the equipment well and the second horizontal tunnel;

[0015] S5, excavating the slag backfilled on the existing construction shaft, and at the same time expanding the existing construction shaft to form a shaft;

[0016] S6. Remove the concrete retaining wall and the construction is completed.

[0017] Preferably, in step S1, when the existing construction transverse tunnel is expanded, the top of the existing construction transverse tunnel is first determined as the transverse tunnel expansion area, and the transverse tunnel expansion area is expanded to form an arch shape.

[0018] Preferably, in step S2, during the backfilling of the existing construction shaft, damage to the temporary support of the existing construction shaft is avoided.

[0019] Preferably, in step S3, after the foundation pit excavation and support of the equipment well are completed, the foundation pit excavation of the equipment well can be carried out. During the excavation, the excavation construction is carried out in sections and steps from top to bottom and the foundation pit support is completed.

[0020] Preferably, in step S4, when excavating the parallel pilot pit, excavation is performed simultaneously from both ends of the parallel pilot pit.

[0021] Preferably, in step S5, when the existing construction shaft is expanded, the vertical surface of the existing construction shaft away from the first horizontal hole is selected as the shaft expansion area, and the shaft expansion area is expanded to form the shaft.

[0022] Due to the adoption of the above technical solution, the beneficial effects of the present invention are as follows:

[0023] (1) In the present invention, the vertical shaft is formed by expanding the existing vertical shaft; the first horizontal tunnel and the second horizontal tunnel are formed by expanding the existing horizontal tunnel, respectively, so that the existing vertical shaft and the existing horizontal tunnel are effectively utilized, achieving the purpose of practicality and economy.

[0024] (2) Using existing construction shafts and existing construction tunnels to construct the ventilation structure of subway section tunnels can reduce construction costs.

[0025] (3) In the present invention, when constructing the ventilation structure of the subway section tunnel, since the vertical shaft is formed by expanding the existing construction vertical shaft; the first horizontal tunnel and the second horizontal tunnel are respectively formed by expanding the existing construction horizontal tunnels. Therefore, the support system of the existing construction vertical shaft and the existing construction horizontal tunnel can be fully utilized to reduce the initial support free surface, effectively control the deformation of the vertical shaft excavation, ensure the safety of the vertical shaft construction, and at the same time reduce the amount of engineering steel and other materials, which is economical and environmentally friendly.

[0026] (4) In the construction method provided by the present invention, the existing construction shaft is separated from the first horizontal tunnel by using a concrete retaining wall, which does not affect the normal operation of the left tunnel and the right tunnel. In addition, the existing construction shaft is backfilled to facilitate the excavation of the equipment well.

[0027] (5) In the present invention, the equipment shaft and the second horizontal tunnel are connected via a parallel pilot tunnel, so the parallel pilot tunnel can be used as a ventilation tunnel and an emergency evacuation passage at the same time.

[0028] (6) The construction method provided by the present invention is simple, easy to operate and has low construction difficulty. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.

[0030] Figure 1 A three-dimensional schematic diagram of the ventilation structure provided by the present invention;

[0031] Figure 2A plan view of the ventilation structure provided by the present invention;

[0032] Figure 3 for Figure 2 Middle AA section view;

[0033] Figure 4 for Figure 2 Middle BB section view;

[0034] Figure 5 for Figure 2 Middle CC section view;

[0035] Figure 6 This is a schematic diagram of expanding and excavating an existing construction horizontal tunnel in the construction method provided by the present invention;

[0036] Figure 7 A schematic diagram of the construction method provided by the present invention after pouring a concrete retaining wall at the connection position of the existing construction shaft and the first horizontal hole and backfilling the existing construction shaft;

[0037] Figure 8 This is a schematic diagram of the construction method provided by the present invention after excavating the equipment well;

[0038] Fig. 9 This is a schematic diagram of the construction method provided by the present invention after excavating parallel pilot pits;

[0039] Fig.10 It is a schematic diagram of excavating the existing construction shaft, backfilling the slag, and expanding the existing construction shaft in the construction method provided by the present invention;

[0040] Fig.11 This is a schematic diagram of the construction method provided by the present invention after the shaft expansion is completed and the concrete retaining wall is removed.

[0041] Explanation of the figure numbers: 1. First transverse tunnel; 2. Left-line tunnel; 3. Second transverse tunnel; 4. Right-line tunnel; 5. Parallel pilot tunnel; 6. Vertical shaft; 6a. Existing construction vertical shaft; 6b. Expansion area of ​​vertical shaft; 7. Equipment shaft; 8. Existing transverse tunnel for construction; 8a. Expansion area of ​​transverse tunnel; 9. Concrete retaining wall. DETAILED DESCRIPTION

[0042] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0043] It should be noted that all directional indications in the embodiments of the present invention (such as up, down, left, right, front, back, etc.) are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0044] In addition, the descriptions of "first", "second", etc. in the present invention are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the ability of ordinary technicians in the field to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0045] Combination Figures 1 to 5 As shown, on the one hand, this embodiment provides a ventilation structure for a subway section tunnel, including a vertical shaft 6 and a left-line tunnel 2 and a right-line tunnel 4 arranged in parallel with each other, and also including a first horizontal tunnel 1 and a second horizontal tunnel 3 arranged at intervals from each other; the first horizontal tunnel 1 is connected and penetrated with the left-line tunnel 2 and the right-line tunnel 4; the second horizontal tunnel 3 is connected and penetrated with the left-line tunnel 2 and the right-line tunnel 4; the vertical shaft 6 is connected with the first horizontal tunnel 1; an equipment shaft 7 is excavated at the top position of the vertical shaft 6, and the mouth of the vertical shaft 6 is located on the bottom wall of the equipment shaft 7; the equipment shaft 7 is connected with the second horizontal tunnel 3 through a parallel guide pit 5; the vertical shaft 6 is formed by expanding and digging using an existing construction vertical shaft 6a; the first horizontal tunnel 1 and the second horizontal tunnel 3 are respectively formed by expanding and digging using existing construction horizontal tunnels 8.

[0046] Combination Figure 2 As shown, the parallel pilot pit 5 is located outside the left-line tunnel 2 or the right-line tunnel 4, and in the top view direction, the parallel pilot pit 5 is parallel to the left-line tunnel 2 or the right-line tunnel 4. If the parallel pilot pit 5 is set between the left-line tunnel 2 and the right-line tunnel 4, when the parallel pilot pit 5 is excavated, it is easy to affect the left-line tunnel 2 or the right-line tunnel 4. Therefore, in this embodiment, the parallel pilot pit 5 is set outside the left-line tunnel 2 or the right-line tunnel 4 to avoid affecting the left-line tunnel 2 and the right-line tunnel 4 when the parallel pilot pit 5 is excavated. Specifically, in this embodiment, the parallel pilot pit 5 is set outside the right-line tunnel 4.

[0047] Combination Figure 1 As shown, the parallel guide pit 5 gradually rises from the position of the second transverse hole 3 to the equipment shaft 7, so that the parallel guide pit 5 has a slope.

[0048] Combination Figure 5As shown, the cross-section upper structure of the first transverse tunnel 1 and the second transverse tunnel 3 is semicircular arch-shaped, and the lower structure is rectangular; the connection through-connection part of the first transverse tunnel 1, the second transverse tunnel 3 and the left-line tunnel 2 and the right-line tunnel 4 is located in the lower rectangular part, and the connection part of the second transverse tunnel 3 and the parallel pilot pit 5 is located in the upper semicircular arch part. The gas between the first transverse tunnel 1 and the equipment shaft 7 is exchanged through the vertical shaft 6, and the gas between the second transverse tunnel 3 and the equipment shaft 7 is exchanged through the parallel pilot pit 5.

[0049] Combination Figures 6 to 11 As shown, this embodiment also provides a construction method for the ventilation structure of the above-mentioned subway section tunnel, comprising the following steps:

[0050] S1. Expand and dig two adjacent existing transverse tunnels 8 to obtain a first transverse tunnel 1 and a second transverse tunnel 3. Specifically, first determine that the top of the existing transverse tunnel 8 is the transverse tunnel expansion area 8a, and expand the transverse tunnel expansion area 8a to form an arch shape.

[0051] S2, backfilling the existing construction shaft 6a: pouring concrete retaining wall 9 at the connection between the existing construction shaft 6a and the first horizontal hole 1, and after the concrete retaining wall 9 reaches the design strength, using slag to backfill the existing construction shaft 6a to the ground level; in the process of backfilling the existing construction shaft 6a, avoid damaging the temporary support of the existing construction shaft 6a. Backfilling slag to avoid excessive particle size of slag, which will lead to difficulties in later excavation.

[0052] S3, excavating the equipment well 7. Specifically, after the foundation pit excavation and support of the equipment well 7 are completed, the foundation pit excavation of the equipment well 7 can be carried out. During the excavation, the excavation construction is carried out in sections and steps from top to bottom and the foundation pit support is completed.

[0053] S4, after the equipment well 7 is excavated to the design elevation, a parallel pilot pit 5 is excavated between the equipment well 7 and the second horizontal tunnel 3. In order to speed up the construction efficiency of the parallel pilot pit 5, when excavating the parallel pilot pit 5, excavation is carried out from both ends of the parallel pilot pit 5 at the same time.

[0054] S5, excavating the slag backfilled on the existing construction shaft 6a, and expanding the existing construction shaft 6a to form the shaft 6. Specifically, the vertical surface of the existing construction shaft 6a away from the first horizontal hole 1 is selected as the shaft expansion area 6b, and the shaft expansion area 6b is expanded to form the shaft 6.

[0055] S6, dismantle the concrete retaining wall 9, and the construction is completed.

[0056] The above description is only a preferred embodiment of the present invention, and does not limit the patent scope of the present invention. All equivalent structural changes made by using the contents of the present invention specification and drawings under the inventive concept of the present invention, or directly / indirectly applied in other related technical fields are included in the patent protection scope of the present invention.

Claims

1. A ventilation structure for a subway tunnel, characterized in that: It comprises a vertical shaft (6), a left-line tunnel (2) and a right-line tunnel (4) arranged in parallel with each other, and also comprises a first horizontal tunnel (1) and a second horizontal tunnel (3) arranged at intervals from each other; The first horizontal tunnel (1) is connected and connected with the left-line tunnel (2) and the right-line tunnel (4); The second horizontal tunnel (3) is connected and connected with the left-line tunnel (2) and the right-line tunnel (4); The vertical shaft (6) is connected to the first horizontal hole (1); An equipment well (7) is excavated at the top of the vertical well (6), and the mouth of the vertical well (6) is located on the bottom wall of the equipment well (7); The equipment well (7) is connected to the second horizontal hole (3) via a parallel pilot pit (5); The vertical shaft (6) is formed by expanding and digging an existing construction vertical shaft (6a); the first horizontal tunnel (1) and the second horizontal tunnel (3) are formed by expanding and digging an existing construction horizontal tunnel (8).

2. A ventilation structure for a subway tunnel as claimed in claim 1, characterized in that: The parallel pilot pit (5) is located outside the left-line tunnel (2) or the right-line tunnel (4), and in a top-view direction, the parallel pilot pit (5) is parallel to the left-line tunnel (2) or the right-line tunnel (4).

3. The ventilation structure of a subway tunnel according to claim 1, characterized in that: In the vertical direction, the parallel guide pit (5) gradually rises from the position of the second horizontal hole (3) to the equipment well (7), so that the parallel guide pit (5) has a slope.

4. The ventilation structure of a subway tunnel according to claim 1, characterized in that: The cross-section upper structure of the first horizontal hole (1) and the second horizontal hole (3) is a semicircular arch, and the lower structure is a rectangle; The connecting parts of the first transverse tunnel (1), the second transverse tunnel (3) and the left-line tunnel (2) and the right-line tunnel (4) are located in the lower rectangular part, and the connecting part of the second transverse tunnel (3) and the parallel guide pit (5) is located in the upper semicircular arch part.

5. A construction method for a ventilation structure of a subway section tunnel according to any one of claims 1 to 4, characterized in that: The following steps are involved: S1, expanding and excavating two adjacent existing construction transverse tunnels (8) to obtain a first transverse tunnel (1) and a second transverse tunnel (3); S2, backfilling the existing construction shaft (6a): pouring a concrete retaining wall (9) at the connection between the existing construction shaft (6a) and the first horizontal hole (1), and then backfilling the existing construction shaft (6a) to the ground level with slag; S3, digging equipment well (7); S4. After the equipment well (7) is excavated to the designed elevation, a parallel pilot pit (5) is excavated between the equipment well (7) and the second horizontal tunnel (3); S5, excavating the slag backfilled on the existing construction shaft (6a), and at the same time expanding the existing construction shaft (6a) to form a shaft (6); S6, dismantle the concrete retaining wall (9), and the construction is completed.

6. The construction method according to claim 5, characterized in that: In the step S1, when the existing construction transverse tunnel (8) is expanded, the top of the existing construction transverse tunnel (8) is first determined as the transverse tunnel expansion area (8a), and the transverse tunnel expansion area (8a) is expanded to form an arch shape.

7. The construction method according to claim 5, characterized in that: In the step S2, during the backfilling process of the existing construction shaft (6a), damage to the temporary support of the existing construction shaft (6a) is avoided.

8. The construction method according to claim 5, characterized in that: In step S3, after the foundation pit excavation and support of the equipment well (7) are completed, the foundation pit excavation of the equipment well (7) can be carried out. During the excavation, the excavation construction is carried out in sections and steps from top to bottom and the foundation pit support is completed.

9. The construction method according to claim 5, characterized in that: In the step S4, when excavating the parallel pilot pit (5), excavation is performed simultaneously from both ends of the parallel pilot pit (5).

10. The construction method according to claim 5, characterized in that: In the step S5, when the existing construction shaft (6a) is expanded, the vertical surface of the existing construction shaft (6a) away from the first horizontal hole (1) is selected as the shaft expansion area (6b), and the shaft expansion area (6b) is expanded to form the shaft (6).

Images