CN213654855U

CN213654855U - Outer wrapping type shield tunnel portal plugging structure

Info

Publication number: CN213654855U
Application number: CN202022618964.6U
Authority: CN
Inventors: 王伟; 史清华; 武慧俊
Original assignee: Hangzhou Yongfu Architectural Design Consulting Co ltd
Current assignee: Hangzhou Yongfu Architectural Design Consulting Co ltd
Priority date: 2020-11-13
Filing date: 2020-11-13
Publication date: 2021-07-09
Anticipated expiration: 2030-11-13

Abstract

The utility model relates to a track traffic construction, especially an outer packet mode shield constructs portal block structure. The problem of water leakage caused by the fact that redundant shield segments are chiseled off to disturb and reinforce a soil body exists in the existing tunnel portal plugging construction. The utility model provides an outer packet type shield constructs portal block structure, including shield tunnel section of jurisdiction and shield tunnel headwall, portal circle steel sheet and portal structure spare, portal structure spare is the portal ring roof beam of establishing reinforcing bar net and cast in situ concrete formation in for, portal ring roof beam outsourcing is fixed at shield tunnel section of jurisdiction tip and is corresponded the entrance to a cave position and even as an organic whole with shield tunnel section of jurisdiction and shield tunnel headwall, portal ring roof beam two is the path end respectively and forms annular mesa in reducing department with the major diameter end, path end face laminating shield tunnel section of jurisdiction terminal surface, major diameter end one side and shield tunnel headwall laminating and the outstanding shield tunnel section of jurisdiction terminal surface end wall of major diameter end, portal circle steel sheet front portion stretches out shield tunnel section of jurisdiction terminal surface laminating annular mesa. The utility model discloses need not to chisel and remove unnecessary shield section of jurisdiction, can not leak and the cost is controllable.

Description

Outer wrapping type shield tunnel portal plugging structure

Technical Field

The utility model belongs to track traffic construction field, especially an outer packet mode shield constructs portal block structure.

Background

At present, subway rail traffic is built in many cities in China, shield construction is mostly adopted among subway stations on the same subway line, after shield tunneling is completed and received, the connecting position of a shield interval tunnel and a shield well main body is blocked, wherein the tunnel part is mainly a shield tunnel segment, the shield well main body part is a shield well tunnel side wall, the part of the side wall corresponding to the opening is also called an end wall, the end wall is practically manufactured by pouring a portal ring beam on the side wall, the portal ring beam is used for reinforcing the open pore structure of the tunnel communicated with the shield interval on the side wall, the plugging is commonly called portal plugging, in particular, a portal ring beam is arranged on the inner side of the portal ring beam, namely the portal position, so that the duct piece and the end wall are connected into a whole, and the place connecting the door and the door is sealed, so that water and soil outside are prevented from entering the tunnel portal to cause water gushing and sand gushing, and the relationship between the ring beam of the tunnel portal and the ring beam of the tunnel portal in the structure is similar to that between a door frame and a door leaf. And after the tunnel portal ring beam is poured, the tunnel portal ring beam and the side wall of the shield well are connected into a whole.

The conventional method for plugging the tunnel portal mostly adopts a built-in flat joint (or called a built-in joint), namely, redundant shield segments extending into a shield well are chiseled, the end surface of the exposed outer side of a tunnel portal ring beam is flush with the inner wall of a main structure of the shield well, namely an end wall, the construction needs to chiseled out the protruded segments in advance, and the engineering risk of water and soil burst outside the shield tunnel is easily caused.

In the current actual construction process, because chiseling unnecessary section of jurisdiction structure in advance, therefore the engineering time is long, portal structure shutoff is timely inadequately, especially when the shield is in sandy stratum, when ground water level is higher, the seepage passageway appears in the disturbance reinforcement soil body easily in the work progress of chiseling, and then causes the risk that shield tunnel outside water and soil gushed suddenly, takes place portal department percolating water problem.

SUMMERY OF THE UTILITY MODEL

The to-be-solved technical problem of the utility model is that owing to chisel out outstanding unnecessary shield segment and to consolidating the soil body disturbance in the construction of current portal shutoff construction, cause the outer water and soil of shield tunnel to gush the risk suddenly and produce the problem of leaking, the utility model provides an outer packet type shield portal block structure, portal block structure need not chisel out the shield tunnel segment and stretch into the unnecessary part in the shield tunnel, effectively avoids the outer water and soil of shield tunnel that causes because chisel out the protruding segment gushes the risk suddenly to the simultaneous control construction cost who ensures the sealed stagnant water effect of portal.

The utility model provides a technical scheme that technical problem adopted: an outer wrapping type shield tunnel portal plugging structure comprises a shield tunnel segment, a shield well end wall, a portal ring steel plate and a portal structure member, wherein the portal structure member is a portal ring beam formed by arranging a reinforcing mesh in the tunnel segment and casting concrete in situ, the portal ring steel plate is pre-buried between the shield tunnel segment and the shield well end wall, the axis of the rear part of the portal ring steel plate extends and is clamped between the shield tunnel segment and the shield well end wall, the front part of the portal ring steel plate extends and is attached to the surface of the shield well end wall, the outer wrapping type tunnel portal ring beam is fixed at the position, corresponding to a portal, of the end part of the shield tunnel segment and is connected with the shield tunnel segment and the shield well end wall into a whole, the portal ring beam is formed by integrally connecting small-diameter ends and large-diameter ends which are arranged at two ends in a split mode, the inner diameters of the small-diameter ends and the large-diameter ends are different, an annular table top is formed at a reducing part, one side of the large-diameter end, which corresponds to the annular table top, is attached to the end wall of the shield well, and the end face of the large-diameter end protrudes out of the end wall of the shield well along the axis direction of the portal ring beam; the front part of the door ring steel plate extends out of the end face of the shield tunnel segment and is attached to the annular table top. The utility model connects the shield tunnel segment and the shield well end wall main body structure into a whole through the outer wrapping type tunnel portal ring beam, seals the gap between the shield tunnel segment surrounding the position of the tunnel portal and the shield well end wall and between the shield tunnel segment and the shield well end wall, prevents outside soil and water from entering the structural range, and ensures the water stop reinforcement effect; one end of the externally-wrapped tunnel portal ring beam protrudes out of the end wall of the shield well serving as the main structure of the shield well, a reinforcing mesh in the tunnel portal ring beam is bound by using reinforcing steel bars, and concrete pouring construction is easy to operate, redundant parts of shield tunnel segments extending into the shield well do not need to be chiseled during construction, meanwhile, the stability and durability of the tunnel portal can be greatly improved by integrally pouring concrete on site, and the construction period is effectively shortened under the condition that the engineering investment is limited and increased; the pre-buried portal ring steel plate is connected with the shield tunnel segment and the shield well end wall into a whole after the portal ring beam is poured, and the pre-buried steel plate plays roles of fixing the water stop curtain cloth plate and welding the temporary water stop steel plate when the shield enters and exits the tunnel.

As further improvement and supplement to the above technical scheme, the utility model discloses a following technical measure: the rear part of the door ring steel plate is provided with an axially extending tube plate, and the front part of the door ring steel plate is provided with a flanging plate which is arranged at the front end of the tube plate and extends radially; the door ring steel plate is formed by welding and splicing a plurality of arc-shaped unit plates around the circumferential direction. The front part of the portal ring steel plate extends radially to be attached to the end wall of the shield well, and the rear part extends axially to be arranged between the end wall of the shield well and the shield tunnel segment; the split arc-shaped unit plates are usually adopted and are generally in three sections, and are welded and spliced on site around the circumferential direction, and in the process of constructing the opening ring beam for reinforcing the opening in the previous period, the spliced opening ring steel plate and the opening ring beam cast on site are fixed together, so that the opening ring steel plate is fixed on the end wall.

The thickness h of the large-diameter end face of the tunnel portal ring beam protruding out of the end wall of the shield well is 350-400 mm. The protruding thickness of the end face of the large-diameter end of the portal ring beam is 350-400 mm, the requirements of plugging effect and structural strength can be met, and the thickness can be properly adjusted according to the requirements of site construction.

And a grouting filling layer formed by secondary grouting is arranged between the shield tunnel duct piece and the shield well end wall at the rear part corresponding to the portal ring beam. The slip casting filling layer that the grout formed can be to shield tunnel section of jurisdiction and shield structure still probably exist between with the headwall gap, and shield tunnel section of jurisdiction outside position is close to the gap on one side of the entrance to a cave promptly and is further filled closely knit especially, and the slip casting filling layer can play the shutoff effect with the tunnel portal ring beam of cast-in-place building in the lump.

And a water stop strip is attached to the end face of the shield tunnel segment. The sealing rod is attached to the end face of the duct piece before the hole door ring beam is poured, and when the sealing rod is expanded when meeting water, the sealing effect can be further enhanced.

The steel reinforcement cage in the tunnel portal ring beam is composed of embedded steel reinforcements on the side wall of the shield well and ring beam steel reinforcements bound on the embedded steel reinforcements, or is composed of embedded steel reinforcements on the side wall of the shield well and ring beam steel reinforcements bound on the embedded steel reinforcements. The steel reinforcement cage is composed of a main body steel reinforcement part and ring beam steel reinforcements bound on the main body steel reinforcement part, wherein the steel reinforcements of the main body can adopt embedded steel reinforcements on the side wall of the shield well, and the embedding construction is simple and convenient; if no embedded steel bar is available, drilling holes on the side wall of the shield well for planting steel bars and constructing by using the planted steel bar glue. In addition, the process of crisscross ligature around pre-buried reinforcing bar or bar planting of ring beam reinforcing bar in the steel reinforcement cage is prior art, and no longer repeated here.

The embedded steel bars or the embedded steel bars are distributed on the end wall of the shield well at the opening along the radial direction to form an inner layer and an outer layer, the embedded steel bars or the embedded steel bars are embedded into the end wall of the shield well at the depth of 320-400 mm, and the embedded steel bars are made of embedded steel bar glue. The shield constructs the interior outer two-layer and encircles the embedded bar or the bar planting that distributes on the well headwall of radial formation, and reinforcing bar or bar planting use the bar planting to glue in this interval also of the wall degree of depth simultaneously, for follow-up ligature preparation steel reinforcement cage and concreting lay the basis down. In addition, the embedded steel bars also need to meet the requirements of relevant national specifications, which is not described in detail in the prior art.

Tunnel portal block structure need not chisel the unnecessary part that the shield constructs the section of jurisdiction and stretches into in the shield tunnel, effectively avoided because chisel the shield that outstanding section of jurisdiction caused constructs the outer soil and water risk of suddenly gushing of tunnel to control construction cost when guaranteeing the sealed stagnant water of tunnel portal.

Drawings

FIG. 1: the plane schematic diagram of the utility model.

FIG. 2: fig. 1 is a partially enlarged view.

FIG. 3: the utility model discloses a section view (not pouring concrete).

FIG. 4: the cross-sectional view along the line a-a of fig. 3 (no concrete casting).

FIG. 5: the cross-sectional view along the line B-B in FIG. 3 (without pouring concrete).

In the figure: 1. the tunnel comprises shield tunnel segments, 2. portal ring beams, 2-1. small-diameter ends, 2-2. large-diameter ends, 2-3. annular table tops, 3. shield well end walls, 4. portal ring steel plates, 4-1. tube plates, 4-2. flanged plates, 5. grouting filling layers, 6. water stop bars, 7. steel bars and 8. ring beam steel bars.

Detailed Description

The invention will be further described with reference to the following description and embodiments in conjunction with the accompanying drawings.

As shown in fig. 1-5, an outer wrapping type shield tunnel portal plugging structure comprises a shield tunnel segment 1, a shield well end wall 3, a portal ring steel plate 4 and a portal structural member, wherein a water stop strip 6 is adhered to the end surface of the shield tunnel segment 1, the portal structural member is a portal ring beam 2 which is internally provided with a reinforcing mesh and formed by cast-in-place concrete, a portal ring steel plate 4 is pre-embedded between a shield tunnel segment 1 and a shield well end wall 3, the axis of the rear part of the portal ring steel plate 4 extends and is clamped between the shield tunnel segment 1 and the shield well end wall 3, the portal ring steel plate 4 in the embodiment is preferably formed by welding and splicing three arc-shaped unit plates around the circumferential direction, the front part is a flange plate 4-2 which is arranged at the front end of the tube plate and extends in the radial direction, the flanged plate 4-2 is attached to the surface of the shield well end wall 3, the rear part of the tunnel portal ring steel plate 4 is an axially extending tube plate 4-1, and the tube plate 4-1 is clamped between the shield tunnel segment 1 and the shield well end wall 3; the tunnel portal ring beam 2 is externally wrapped and fixed at the position of the end part of the shield tunnel segment 1 corresponding to the tunnel portal and is connected with the shield tunnel segment 1 and the shield well end wall 3 into a whole, the tunnel portal ring beam 2 is formed by integrally connecting small-diameter ends 2-1 and large-diameter ends 2-2 which are arranged at two ends in rows, the inner diameters of the small-diameter ends and the large-diameter ends are consistent and the outer diameters of the small-diameter ends and the large-diameter ends are different, the diameter-variable part forms an annular table top 2-3, the end face of the small-diameter end 2-1 is attached to the end face of the shield tunnel segment 1, one side of the large-diameter end 2-2 corresponding to the annular table top 2-3 is attached to the end wall 3 of the shield well, the end face of the large-diameter end 2-2 protrudes out of the end wall 3 of the shield well along the axial direction of the portal ring beam 2, the thickness h of the large-diameter end 2-2 protruding out of the end wall 3 of the shield well is preferably 400mm in the embodiment, and the annular table top 2-3 is also attached to the front part of the portal ring steel plate 4 protruding out of the end face of the; a grouting filling layer 5 formed by secondary grouting is arranged between the shield tunnel segment 1 and the shield well end wall 3 at the rear part corresponding to the portal ring beam 2; in the embodiment, the steel bar mesh in the portal ring beam 2 is preferably composed of embedded bars 7 distributed circumferentially on the shield well end wall 3 and ring beam steel bars 8 bound on the embedded bars, one end of each embedded bar 7 is embedded into the shield well end wall 3, the wall embedding depth is 320-400 mm, the other end of each embedded bar extends out of the shield well end wall 3, the embedded bars 7 are distributed radially on the shield well end wall 3 at the portal to form an inner layer and an outer layer, and the embedded bars are required to be glued during rib embedding. In addition, the embedded steel bars can be replaced by embedded steel bars of the shield well end wall 3, the embedded steel bars are poured and fixed when the tunnel portal ring beam is constructed, and the embedded steel bars are left on the shield well end wall formed by the tunnel portal ring beam after pouring.

The utility model discloses a shield tunnel section of jurisdiction and shield well side wall major structure are connected into whole through outer packet type portal ring beam and are realized the shutoff, seal the space that surrounds between shield tunnel section of jurisdiction and the shield well headwall, prevent effectively that outside soil and water from getting into the structural range, ensure stagnant water reinforcement effect; the externally-wrapped tunnel portal ring beam part protrudes out of the end wall of the shield well, a reinforcing mesh in the tunnel portal ring beam is easy to operate through ring beam reinforcing steel binding and concrete pouring construction, the redundant part of a shield tunnel segment extending into the shield well does not need to be specially chiseled during tunnel portal ring beam construction, meanwhile, the stability and the durability of the tunnel portal ring beam can be greatly improved through concrete on-site integral pouring, and the construction period is effectively shortened under the condition that the engineering investment is increased in a limited mode. The utility model discloses a construction can be carried out according to following step:

(1) before construction, soil mass behind the segment wall of the shield tunnel is subjected to secondary grouting and filling compaction;

(2) stripping off the embedded steel bars of the main structure or planting the steel bars on the structure;

(3) in the process of manufacturing the reinforcement cage, bound ring beam reinforcements are reliably welded with the hole door ring steel plate; if the shield tunnel segment at the tunnel portal is broken, changing the ring beam steel bar part into a planted bar to be implanted into the shield tunnel segment structure;

(4) binding ring beam steel bars of the tunnel door to form an integral steel bar cage;

(5) erecting a template and pouring a concrete structure of the portal ring beam.

Claims

1. An outer wrapping type shield tunnel portal plugging structure comprises a shield tunnel segment (1), a shield well end wall (3), a portal ring steel plate (4) and a portal structural member, wherein the portal structural member is a portal ring beam (2) formed by arranging a reinforcing mesh and casting concrete in situ, the portal ring steel plate (4) is pre-embedded between the shield tunnel segment (1) and the shield well end wall (3), the axis of the rear part of the portal ring steel plate (4) extends and is clamped between the shield tunnel segment (1) and the shield well end wall (3), the front part of the portal ring steel plate (4) extends out and is attached to the surface of the shield well end wall (3), the outer wrapping type tunnel ring beam (2) is fixed at the position, corresponding to a portal, of the end part of the shield tunnel segment (1) and is connected with the shield tunnel segment (1) and the shield well end wall (3) into a whole, the portal ring beam (2) is formed by integrally connecting a small-diameter end (2-1) and a large-diameter end (2-2) which are arranged at two ends, the inner diameters of the small-diameter end and the large-diameter end are consistent and the outer diameters are different, an annular table top (2-3) is formed at the diameter changing position, the end face of the small-diameter end (2-1) is attached to the end face of a shield tunnel segment (1), one side, corresponding to the annular table top (2-3), of the large-diameter end (2-2) is attached to a shield well end wall (3), and the end face of the large-diameter end (2-2) protrudes out of the shield well end wall (3) along the axial direction of a portal ring beam (2); the front part of the door ring steel plate (4) extends out of the end surface of the shield tunnel segment (1) and is attached to the annular table top (2-3).

2. The outer wrapping type shield tunnel portal blocking structure according to claim 1, wherein the tunnel portal ring steel plate (4) is provided with an axially extending tube plate (4-1) at the rear part and a radially extending flanged plate (4-2) at the front end of the tube plate at the front part; the door ring steel plate (4) is formed by welding and splicing a plurality of arc-shaped unit plates around the circumferential direction.

3. The externally wrapped shield tunnel portal plugging structure according to claim 1, wherein the thickness h of the end face of the large diameter end (2-2) of the tunnel portal ring beam (2) protruding out of the shield well end wall (3) is 350-400 mm.

4. The externally wrapped shield tunnel portal plugging structure according to claim 1, characterized in that a grouting filling layer (5) formed by secondary grouting is arranged between the shield tunnel segment (1) and the shield well end wall (3) at the rear part of the corresponding portal ring beam (2).

5. The externally-wrapped shield tunnel portal plugging structure according to claim 1, wherein a water stop strip (6) is attached to the end face of the shield tunnel segment (1).

6. The externally wrapped shield tunnel portal plugging structure according to any one of claims 1 to 5, wherein the reinforcing mesh in the tunnel portal ring beam (2) is composed of embedded reinforcing bars circumferentially distributed on the shield well end wall (3) and ring beam reinforcing bars (8) bound thereon, and one end of each embedded reinforcing bar extends out of the shield well end wall (3); or the reinforcing mesh consists of embedded bars (7) which are distributed on the end wall (3) of the shield well in the circumferential direction and ring beam reinforcing bars (8) which are bound on the embedded bars.

7. The externally wrapped shield tunnel portal plugging structure according to claim 6, wherein the embedded steel bars or the embedded steel bars (7) are distributed on the shield tunnel end wall (3) of the tunnel portal in an inner and outer layer along the radial direction, the embedded steel bars or the embedded steel bars (7) are embedded into the shield tunnel end wall (3) with the depth of 320-400 mm, and the embedded steel bars (7) are made of embedded steel bar glue.