CN218759877U

CN218759877U - Rich water ultra-deep subway shield tunnel terminal reinforcing structure that starts

Info

Publication number: CN218759877U
Application number: CN202221845740.1U
Authority: CN
Inventors: 杨平; 韩琳亮; 靳贻杰; 王加辉; 张婷; 朱泽萱
Original assignee: Nanjing Forestry University
Current assignee: Nanjing Forestry University
Priority date: 2022-07-18
Filing date: 2022-07-18
Publication date: 2023-03-28
Anticipated expiration: 2032-07-18

Abstract

The utility model discloses an end reinforced structure starts in rich water ultra-deep subway shield tunnel, including end well envelope, cement soil plain wall reinforcement body. The utility model adopts multi-row TRD equal-thickness cement mixing wall lap joint reinforcement, has wide applicable stratum, low mechanical equipment height and large reinforcement depth, can meet the reinforcement of the starting end of a shield tunnel with the buried depth of 60m, has continuous wall formation, compact and uniform depth direction, good water-proof property and little influence on the surrounding environment; an RJP high-pressure jet grouting pile reinforcing body is arranged between the end well enclosure structure and the cement-soil plain wall reinforcing body, so that leakage at a joint position is prevented, the reinforcing depth is large, and the quality is reliable; a plurality of rows of freezing pipes are arranged on the outer side of the end well enclosure structure for reinforcement and reinforcement to form a closed freezing curtain, so that the risk of sand gushing and collapse during tunnel portal chiseling is reduced, and the shield starting safety coefficient is further improved; the plain concrete underground continuous wall and the end well enclosure structure form a closed structure, and the underground water on the outer side is prevented from flowing into the reinforcing range of the starting end.

Description

Rich water ultra-deep subway shield tunnel terminal reinforcing structure that starts

Technical Field

The utility model relates to a shield tunnel construction technical field especially relates to a rich water ultra-deep subway shield tunnel end reinforcing structure that originates.

Background

The shield initiation is one of key links in the shield construction, is also a link which is easy to cause safety accidents, and is characterized in that the end is reinforced before the shield initiation, so that the exposed soil body after the tunnel portal is broken away has certain self-stability capability, the hydraulic connection between a reinforced area and the outside is isolated, and the success or failure of the shield initiation is directly determined by the reinforcement of the end. The current common end reinforcing method comprises the following steps: grouting, jet grouting, triaxial mixing, freezing, and the like.

Along with the continuous development of underground space, the tunnel burial depth is continuously increased, the stratum conditions and the surrounding environment are more complicated and changeable, particularly, in the reinforcing of the starting end of the ultra-deep shield tunnel in a water-rich stratum, cement slurry is difficult to effectively reserve under the seepage action of underground water when a jet grouting pile or grouting is adopted, and the peripheral pressure is continuously increased along with the increase of the reinforcing depth, so that the effective pile diameter of a reinforcing body is reduced, the lap joint length between piles is insufficient, gaps can exist between adjacent piles in the deep part, water can not be effectively prevented, and the shield construction risk is increased; when adopting triaxial stirring stake to consolidate, it is difficult to guarantee to consolidate solid homogeneity and water barrier, and consolidates the degree of depth and is limited, probably causes when abolishing the portal and gushes risks such as water, sand gushes. Therefore, in the starting end of the water-rich ultra-deep shield tunnel, a reinforcing structure capable of improving the soil strength and water resistance of the end is urgently needed, the reinforcing body is ensured to be uniform and compact along the depth direction, and the shield is ensured to be started safely.

SUMMERY OF THE UTILITY MODEL

The utility model aims at solving the shortcoming that exists among the prior art, and the end reinforced structure that starts of rich water ultra-deep subway shield tunnel that proposes, this structure has improved rich water ultra-deep subway shield tunnel and has started end soil body intensity and water proof performance, ensures to follow the even closely knit of degree of depth direction, guarantees that the shield constructs safety and starts.

In order to realize the purpose, the utility model adopts the following technical scheme:

the utility model provides a rich water ultra-deep subway shield tunnel starts end reinforced structure, includes end well envelope, cement plain wall reinforcement body, plain concrete underground continuous wall, end well and shield tunnel, end well envelope encircles the end well setting, and cement plain wall reinforcement body is located the outside of end well envelope, and plain concrete underground continuous wall is the U-shaped and encircles and set up in cement plain wall reinforcement body periphery to be connected with end well envelope, shield tunnel run through end well envelope, cement plain wall reinforcement body and plain concrete underground continuous wall in proper order, set up the reinforcement subassembly between cement plain wall reinforcement body and the end well envelope.

Preferably, the reinforcing component comprises an RJP high-pressure jet grouting pile reinforcing body and a vertical freezing pipe, the RJP high-pressure jet grouting pile reinforcing body is arranged close to the end well enclosure structure, and the vertical freezing pipe is vertically arranged inside the RJP high-pressure jet grouting pile reinforcing body and the cement-soil plain wall reinforcing body.

Preferably, the cement-soil plain wall reinforcing body consists of a plurality of rows of TRD equal-thickness cement-soil mixing walls, the thickness of each row is 800mm, and the lap joint width between the rows is not less than 350mm.

Preferably, the depth of the cement-soil plain wall reinforcing body is 3-4m from the ground surface to the position below the bottom of the shield tunnel, and the transverse width is 3-4m from the left side to 3-4m from the right side of the shield tunnel.

Preferably, the RJP high-pressure jet grouting pile reinforcing body and the plain concrete underground continuous wall are embedded into a waterproof layer not less than 1m.

Preferably, the vertical freezing pipes are arranged in 2 rows in a quincunx manner, the transverse spacing of the vertical freezing pipes is 850mm, and the longitudinal row spacing is 850mm.

Preferably, the distance between the cement-soil plain wall reinforcing body and the end well enclosure structure is 600mm.

Preferably, the distance between the bottom of the vertical freezing pipe and the bottom of the cement plain wall reinforced body is not less than 0.5m.

Compared with the prior art, the beneficial effects of the utility model are that:

(1) The soil body is lapped and reinforced by adopting a plurality of rows of TRD equal-thickness cement soil stirring walls, the applicable stratum is wide, the height of mechanical equipment is low, the reinforcing depth is large, the starting end reinforcement of a shield tunnel with the buried depth of 60m can be met, the wall formation is continuous, the depth direction is compact and uniform, the water-resisting property is good, and the influence on the surrounding environment is small;

(2) An RJP high-pressure jet grouting pile reinforcing body is arranged between the end well enclosure structure and the cement-soil plain wall reinforcing body, so that leakage at a joint position is prevented, the reinforcing depth is large, and the quality is reliable;

(3) A plurality of rows of freezing pipes are arranged outside the enclosing structure of the end well for reinforcement and reinforcement to form a closed freezing curtain, so that the risk of sand gushing and collapse during the chiseling of the tunnel portal is reduced, and the safety coefficient of the shield starting is further improved;

(4) The plain concrete underground continuous wall and the end well enclosure structure form a closed structure, and outside underground water is prevented from flowing into the reinforcing range of the starting end.

Drawings

In order to more particularly and intuitively illustrate an embodiment of the present invention or a prior art solution, a brief description of the drawings needed for use in the description of the embodiment or the prior art will be provided below.

Fig. 1 is a schematic structural diagram of the present invention;

fig. 2 is a cross-sectional view of fig. 1.

In the figure: the method comprises the following steps of 1-end well enclosure structure, 2-RJP high-pressure jet grouting pile reinforcing body, 3-vertical freezing pipe, 4-cement soil plain wall reinforcing body, 5-plain concrete underground continuous wall, 6-end well and 7-shield tunnel.

Detailed Description

The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments.

Referring to fig. 1-2, the water-rich ultra-deep subway shield tunnel starting end reinforcement structure comprises an end well enclosure structure 1, a cement-soil plain wall reinforcement body 4, a plain concrete underground continuous wall 5, an end well 6 and a shield tunnel 7, wherein the end well enclosure structure 1 is arranged around the end well 6, the cement-soil plain wall reinforcement body 4 is positioned on the outer side of the end well enclosure structure 1, the plain concrete underground continuous wall 5 is arranged around the cement-soil plain wall reinforcement body 4 in a U-shaped mode and is connected with the end well enclosure structure 1, the shield tunnel 7 sequentially penetrates through the end well enclosure structure 1, the cement-soil plain wall reinforcement body 4 and the plain concrete underground continuous wall 5, and a reinforcement assembly is arranged between the cement-soil plain wall reinforcement body 4 and the end well enclosure structure 1.

In this embodiment, the reinforcing component includes RJP high pressure jet grouting pile reinforcing body 2 and perpendicular freezing pipe 3, and RJP high pressure jet grouting pile reinforcing body 2 is close to end well envelope 1 and sets up, freezes the pipe 3 perpendicularly and sets up inside RJP high pressure jet grouting pile reinforcing body 2 and cement plain wall reinforcing body 4.

In the embodiment, the cement-soil plain wall reinforcing body 4 consists of a plurality of rows of TRD equal-thickness cement-soil mixing walls, the thickness of each row is 800mm, the lap joint width between the rows is not less than 350mm, the verticality of the wall body is not more than 1/400, the cement mixing amount is 23%, the unconfined compressive strength of the reinforcing body is not less than 0.8MPa within 28 days, the impermeability coefficient is not more than 10-7cm/s, the depth of the cement-soil plain wall reinforcing body 4 is 3-4m from the earth surface to the bottom of the shield tunnel 7, the transverse width is 3-4m from the left side to the right side of the shield tunnel 7, the RJP high-pressure jet grouting pile reinforcing body 2 and the plain concrete underground continuous wall 5 are embedded into a watertight layer which is not less than 1m.

The TRD method is characterized in that a chain saw type cutting box inserted into a foundation is connected with a host, cement slurry is moved, cut and poured along the transverse direction, convection is formed in a groove, and mixing, stirring and consolidation are carried out to form the equal-thickness cement soil underground stirring wall.

In the embodiment, the distance 600mm between the cement-soil plain wall reinforcing body 4 and the end well enclosure structure 1 is 600mm, and 600mm is a gap area, and the gap area is provided with the RJP high-pressure jet grouting pile reinforcing body 2, and the RJP high-pressure jet grouting pile reinforcing body 2 is formed by meshing single-row piles with the diameter of 1500mm and the distance of 1100mm and is embedded into the impermeable layer 1m.

By arranging the single-row RJP high-pressure jet grouting pile reinforcing body 2, a hydraulic channel at the joint of the end well enclosure structure 1 and the cement-soil plain wall reinforcing body 4 is isolated, the strength and the diameter of the pile body are far greater than those of a common jet grouting pile, the reinforcing quality is reliable, and the depth is large.

The junction of the reinforcing body and the end well enclosure structure 1 is easy to gush sand, discharge water and collapse when a tunnel door is chiseled. Therefore, the vertical freezing pipe 3 is arranged on the freezing outer side, so that the soil body is frozen to form a closed freezing curtain, the soil body at the junction can be effectively reinforced, and risks such as collapse, water burst, sand burst and the like are avoided.

The vertical freezing pipes 3 are low-carbon steel pipes with the diameter of 89mm, 2 rows are arranged in a quincunx mode, the distance between every two transverse freezing pipes is 850mm, the distance between every two longitudinal rows is 850mm, and the distance between the bottom of each vertical freezing pipe 3 and the bottom of the cement-soil plain wall reinforcing body 4 is 0.5m.

The 5 wall thickness 800mm of plain concrete underground continuous wall is U-shaped and encircles the setting of end reinforcing scope, can effectively prevent outside groundwater from flowing into the reinforcement district. The utility model discloses a multiple method is united and is consolidated shield and construct the end of starting, ensures end soil body homogeneity, self-reliance nature and water proof nature.

The above, only be the embodiment of the preferred of the present invention, but the protection scope of the present invention is not limited thereto, and any person skilled in the art is in the technical scope of the present invention, according to the technical solution of the present invention and the utility model, which are designed to be replaced or changed equally, all should be covered within the protection scope of the present invention.

Claims

1. The utility model provides a rich water ultra-deep subway shield tunnel starts end reinforced structure, includes end well envelope (1), cement plain wall reinforcement body (4), plain concrete underground continuous wall (5), end well (6) and shield tunnel (7), its characterized in that, end well envelope (1) encircles end well (6) and sets up, and cement plain wall reinforcement body (4) are located the outside of end well envelope (1), and plain concrete underground continuous wall (5) are the U-shaped and encircle and set up in cement plain wall reinforcement body (4) periphery to be connected with end well envelope (1), shield tunnel (7) run through end well envelope (1), cement plain wall reinforcement body (4) and plain concrete underground continuous wall (5) in proper order, set up between cement plain wall reinforcement body (4) and end well envelope (1) and consolidate the subassembly.

2. The water-rich ultra-deep subway shield tunnel starting end reinforcing structure is characterized in that the reinforcing assembly comprises an RJP high-pressure jet grouting pile reinforcing body (2) and a vertical freezing pipe (3), the RJP high-pressure jet grouting pile reinforcing body (2) is arranged close to the end well enclosure structure (1), and the vertical freezing pipe (3) is vertically arranged inside the RJP high-pressure jet grouting pile reinforcing body (2) and a cement soil plain wall reinforcing body (4).

3. The water-rich ultra-deep subway shield tunnel starting end reinforcing structure as claimed in claim 2, wherein said cement-soil plain wall reinforcing body (4) is composed of a plurality of rows of TRD equal-thickness cement-soil mixing walls, each row has a thickness of 800mm, and the width of lap joint between rows is not less than 350mm.

4. The water-rich ultra-deep subway shield tunnel starting end reinforcing structure as claimed in claim 3, wherein said cement-soil plain wall reinforcing body (4) has a depth from the earth's surface to 3-4m below the bottom of the shield tunnel (7), and a transverse width from 3-4m on the left side to 3-4m on the right side of the shield tunnel (7).

5. The reinforcing structure for the starting end of the water-rich ultra-deep subway shield tunnel according to claim 4, wherein the RJP high-pressure jet grouting pile reinforcing body (2) and the plain concrete underground continuous wall (5) are embedded in a water-impermeable layer of not less than 1m.

6. The structure for reinforcing the starting end of the water-rich ultra-deep subway shield tunnel according to claim 5, wherein said vertical freezing pipes (3) are arranged in 2 rows in a quincunx shape, the horizontal spacing of the vertical freezing pipes (3) is 850mm, and the longitudinal row spacing is 850mm.

7. The water-rich ultra-deep subway shield tunnel starting end reinforcing structure according to claim 6, wherein the distance between said cement-soil wall reinforcing body (4) and end well enclosure (1) is 600mm.

8. The water-rich ultra-deep subway shield tunnel starting end reinforcing structure as claimed in claim 7, wherein said vertical freezing pipe (3) is not less than 0.5m from the bottom of cement-soil plain wall reinforcing body (4).