Shield segment structure of a reserved hole portal shield section connecting passage

Abstract

A shield interval connecting channel steel pipe structure of a reserved hole door, comprising two ring steel pipes fixed as a whole, each ring steel pipe corresponding to a pipe ring composed of standard block A2, standard block A3, adjacent block B1, top sealing block K1, adjacent block C1 and special block S connected in sequence clockwise; the special block S corresponding to a central angle of 72 degrees and symmetrically arranged on the horizontal axis of the pipe ring, the hole door frame pipe S1 being a half door frame shape, the hole door sub-pipe S2, the hole door sub-pipe S4 and the hole door sub-pipe S3 arranged in the frame in sequence clockwise, the hole door sub-pipe S4 being a wedge-shaped pipe; the hole door frame pipe S1 of the two ring pipes being symmetrically arranged to form the whole door frame, and the hole door sub-pipe S2, the hole door sub-pipe S3 and the hole door sub-pipe S4 arranged in the frame of the hole door frame pipe S of the two ring pipes and symmetrically arranged side by side to form the hole door. The application avoids the risk of opening the hole door of the connecting channel and ensures the construction safety of the connecting channel.

Description

Technical Field

[0001] This invention belongs to the field of subway shield tunnel technology, specifically relating to a steel segment structure for a shield tunnel section connecting passage with a reserved portal. Background Technology

[0002] With the continuous development of urbanization, more and more cities are choosing subways as the main form of public transportation, providing citizens with an efficient and convenient mode of public transport. Shield tunneling is the primary construction method for subway tunnels. The "Subway Design Code" stipulates that connecting passages should be provided between two single-track tunnel sections, and the distance between two adjacent connecting passages should not exceed 600 meters. Parallel, counter-opening Class A fire doors should be installed within the connecting passages. However, the construction of connecting passages is a major source of risk in shield tunneling.

[0003] Currently, the commonly used shield tunneling method uses concrete segments for lining. At connecting passages, it is necessary to break through the concrete segments to create an opening, which then needs to be reinforced. The size of the broken opening must be larger than the portal size to allow space for the reinforcement of the side beams. Breaking through the segments disrupts the overall load-bearing structure of the segments. Creating the opening first and then reinforcing it requires close coordination of the procedures, involves a change in the load-bearing system, and makes the construction process complex and extremely risky, especially in water-rich silty sand strata where water seepage is a frequent occurrence.

[0004] Currently, steel pipe segments are also used in connecting passages because their stiffness and strength are much greater than concrete pipe segments, significantly improving safety. However, this still requires cutting steel pipe segments at the opening, disrupting the structural system of the segments, and the risks remain significant. This issue urgently needs to be addressed. Summary of the Invention

[0005] This invention provides a steel segment structure for a shield tunnel section connecting passage with a reserved portal, in order to solve the technical problem of avoiding the risk of opening a portal in the connecting passage and ensuring the construction safety of the connecting passage without damaging the overall stress structure system of the segments.

[0006] This invention is achieved through the following technical solution:

[0007] A steel segment structure for a shield tunnel section connecting passage with a reserved portal includes two adjacent rings of steel segments fixed as a whole within the portal area of ​​the connecting passage. The characteristic is that each ring of steel segments corresponds to a standard block A2 1, standard block A3 2, adjacent block B1 3, capping block K1 4, adjacent block C1 5, and special block S6 connected in a clockwise sequence to form a segment ring.

[0008] The special block S has a central angle of 72° and is arranged symmetrically above and below the horizontal axis of the segment ring. The standard block A2 has a central angle of 72° and is arranged clockwise next to the lower edge of the special block S. The standard block A3 has a central angle of 72° and is arranged clockwise next to the standard block A2. The adjacent block B1 has a central angle of 68° and is arranged clockwise next to the standard block A3. The adjacent block C1 has a central angle of 68° and is arranged counterclockwise next to the upper edge of the special block S. The capping block K1 has a central angle of 8° and is arranged in a wedge shape between the adjacent blocks B1 and C1.

[0009] The special block S6 includes portal frame segment S1 61, portal segment segment S2 62, portal segment segment S3 63, and portal segment segment S4 64. The portal frame segment S1 is in the shape of a half-portal frame, and the portal segment segments S2 62, S4 64, and S3 63 are arranged clockwise within the half-portal frame. The portal segment segment S4 is a wedge-shaped segment, and the adjacent edges of the portal segment segments S2, S3, and S4 are corresponding wedge-shaped slopes. The portal frame segments S1 of the two ring segments are symmetrically arranged to form the entire portal frame. The portal segment segments S2, S3, and S4 arranged side by side and symmetrically within the half-portal frame of the portal frame segments S1 of the two ring segments form the portal.

[0010] The aforementioned steel segment structure for a shield tunnel section connecting passage with a reserved portal is characterized by each segment being a steel structure connected to each other by bolts. The outer side is an arc-shaped steel plate, the inner side is a steel gusset plate, and the inner and outer sides are connected by ribs. The segments are also surrounded by end plates to form a whole. The width and thickness of the steel segments are the same as those of the reinforced concrete segments outside the connecting passage. The circumferential ribs 8 and radial ribs 9 of each steel segment are aligned to ensure that there are no abrupt changes in the dimensions of the tunnel sidewall.

[0011] The steel segment structure at the shield tunnel section connecting passage with reserved portal is described above, wherein the angle between the connecting surface of the portal segment S4, portal segment S2, and portal segment S3 and the radial line is 14°.

[0012] This invention relates to a pre-reserved portal steel segment, where the location of the connecting passage entrance is pre-defined on the steel segment. When the tunnel boring machine (TBM) reaches the connecting passage, the steel segments are assembled, forming a single, circular ring. During the construction of the connecting passage, the portal segment can be removed by unplugging the segment connecting bolts from inside the tunnel, thus avoiding the need to cut or chisel away the segments to create the entrance and prevent damage to the segment's load-bearing system. Construction is convenient and quick, involves no load transfer, and significantly reduces construction risks.

[0013] The beneficial effects of this invention are:

[0014] This invention avoids the risks associated with opening doors in connecting passages, ensuring the safety of connecting passage construction. Attached Figure Description

[0015] Figure 1 This is a schematic front elevation view of the segment ring of the present invention.

[0016] Figure 2 This is a schematic diagram of the two-ring segment side elevation (including the portal side elevation) of the present invention.

[0017] Figure 3 This is a schematic diagram of the S1 elevation (a mirror image of the two ring steel pipe segments S1 and S1').

[0018] Figure 4 This is a schematic diagram of the S1 cross-section (a mirror image of the two-ring steel pipe segments S1 and S1').

[0019] Figure 5 This is a schematic diagram of the S2 elevation (a mirror image of the two-ring steel pipe segments S2 and S2').

[0020] Figure 6 This is a schematic diagram of the S2 cross-section (a mirror image of the two-ring steel pipe segments S2 and S2').

[0021] Figure 7 This is a schematic diagram of the S3 elevation (a mirror image of the two-ring steel pipe segments S3 and S3').

[0022] Figure 8 This is a schematic diagram of the S3 cross-section (a mirror image of the S3 and S3' sections of the two-ring steel pipe segments).

[0023] Figure 9 This is a schematic diagram of the S4 elevation (a mirror image of the two-ring steel pipe segments S4 and S4').

[0024] Figure 10 This is a schematic diagram of the S4 cross-section (a mirror image of the S4 and S4' sections of the two-ring steel pipe segments).

[0025] Figure 11 This is a schematic diagram of the A2 elevation (A3 is a mirror image of A2).

[0026] Figure 12 This is a schematic diagram of section A2 (A3 is a mirror image of A2).

[0027] Figure 13 This is a schematic diagram of the B1 elevation (C1 is a mirror image of B1).

[0028] Figure 14 This is a schematic diagram of the cross-section B1 (C1 is a mirror image of B1).

[0029] Figure 15 This is a schematic diagram of the K1 elevation.

[0030] Figure 16 This is a schematic diagram of the cross-section of K1.

[0031] Explanation of the attached drawing numbers:

[0032] 1. Standard block A2, 2. Standard block A3, 3. Adjacent block B1, 4. Capping block K1, 5. Adjacent block C1, 6. Special block S, 7. Portal frame segment S1, 8. Portal segment S2, 9. Portal segment S3, 10. Portal segment S4, 11. Bolt, 12. Circumferential rib, 13. Radial rib, 14. Bolt hole. Detailed Implementation

[0033] The specific embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0034] See Figure 1-16 As shown, the present invention discloses a steel pipe segment structure for a shield tunnel section connecting passage with a reserved portal, comprising two adjacent rings of steel pipe segments fixed as a whole within the portal area of ​​the connecting passage. See also... Figure 1 As shown, each ring of steel pipe segments includes standard block A2 1, standard block A3 2, adjacent block B1 3, capping block K1 4, adjacent block C1 5, and special block S6 connected in a clockwise sequence to form a pipe segment ring, and the above blocks on the two rings of steel pipe segments correspond to each other;

[0035] The special block S has a central angle of 72° and is arranged symmetrically above and below the horizontal axis of the segment ring. The standard block A2 has a central angle of 72° and is arranged clockwise next to the lower edge of the special block S. The standard block A3 has a central angle of 72° and is arranged clockwise next to the standard block A2. The adjacent block B1 has a central angle of 68° and is arranged clockwise next to the standard block A3. The adjacent block C1 has a central angle of 68° and is arranged counterclockwise next to the upper edge of the special block S. The capping block K1 has a central angle of 8° and is arranged in a wedge shape between the adjacent blocks B1 and C1.

[0036] See Figure 2-4 As shown, where Figure 2 The special block S6 comprises two adjacent rings of steel pipe segments, including the side facade of the portal, fixed as a whole within the portal area of ​​the connecting passage. The special block S6 includes portal frame segment S1 61, portal segment segment S2 62, portal segment segment S3 63, and portal segment segment S4 64. Portal frame segment S1 61 is in the shape of a semi-portal frame, and within this semi-portal frame, portal segment segments S2 62, S4 64, and S3 63 are arranged clockwise in sequence. (See [reference]). Figure 9-10 As shown, the portal segment S4 is a wedge-shaped segment, see [reference]. Figure 5-8As shown, the adjacent edges of the portal segment S2 62, portal segment S3 63, and portal segment S4 are corresponding wedge-shaped inclined surfaces; see also Figure 2 As shown, the portal frame segments S1 61 of the two adjacent ring segments are symmetrically arranged to form the entire portal frame. The portal segment segments S2 62, S3 63 and S4 64 arranged side by side within the half-port frame of the portal frame segments S1 of the two ring segments form the portal.

[0037] See Figure 1-16 As shown, the steel segment structure at the shield tunnel section connecting passage with a reserved portal is described above. Each segment is a steel structure and they are connected to each other by bolts. (See also...) Figure 3 , Figure 5 , Figure 7 , Figure 9 , Figure 11 , Figure 13 , Figure 15 Bolt holes 10 are provided on the left and right sides of the tunnel segment for easy bolt connection. The outer side is a curved steel plate, and the inner side is a steel gusset plate. Ribs, including circumferential ribs 8 and radial ribs 9, are located between the inner and outer sides. End plates surround the entire segment. The width and thickness of the steel segments are the same as those of the reinforced concrete segments outside the connecting passage. The circumferential ribs 8 and radial ribs 9 of each steel segment are aligned to ensure no abrupt changes in the tunnel sidewall dimensions. Alignment of the circumferential and radial ribs ensures more reasonable stress distribution.

[0038] The steel segment structure for the shield tunnel section connecting passage with a reserved portal, wherein the angle between the connecting surface (i.e., the wedge-shaped inclined surface) and the radial line of the portal segment S4, S2, and S3 is 14°. (See also...) Figure 6 , Figure 8 , Figure 10 The angle between the inclined side and the radial line is 14° for easy disassembly; the wedge-shaped bevel is a radially inclined wedge shape. (See also...) Figure 15 The capping block K1 shown is inclined in a wedge shape on the axial surface.

[0039] Example

[0040] This invention was tested in a pilot section of a project, using the shield tunneling method. The section length was 941.1m, exceeding 600m, and included a connecting passage. The strata at the connecting passage site, from the ground surface downwards, consisted of plain fill, silty soil, silt, medium sand, and strongly weathered silty mudstone. The connecting passage was buried at a depth of 15.2m, in strata consisting of silt and medium sand, with the groundwater level 1.5m below the ground surface.

[0041] The two rings of tunnel segments in the connecting passage of this shield tunnel section use steel segments with reserved portals, while the rest use reinforced concrete segments. The outer diameter of the segments is 6m, the inner diameter is 5.4m, and the ring width of the segments is 1.5m.

[0042] After the tunnel boring machine (TBM) starts from the working shaft, as it advances, reinforced concrete segments are assembled first. Upon reaching the connecting passage, two rings of steel segments for the pre-reserved portal are assembled. Then, concrete segments are assembled until the TBM reaches the receiving shaft for reception. After ground reinforcement, the connecting passage is constructed. Once the conditions for opening the tunnel are met, see [link to relevant documentation]. Figure 2 As shown, the portal segments S4→S2→S3 of one ring are disassembled in the following order, along with the portal segments S4'→S2'→S3' of another ring, forming the portal opening. Then, the tunnel excavation is carried out. Here, S4', S2', and S3' represent portal segments of another ring of segments that are symmetrically adjacent to S4, S2, and S3. The portal segments S4', S2', and S3', symmetrically arranged in the two rings, together with S4, S2, and S3, form a portal.

[0043] No accidents such as water or sand inrush occurred during the construction process, and no water leakage was observed at the interface of the connecting passage.

[0044] The main structure of the steel tunnel segment consists of a 16mm thick outer arc-shaped steel plate and an inner 30mm thick arc-shaped steel gusset plate. 20mm thick circumferential and longitudinal ribs are installed between the inner and outer sides of the steel segment, and 30mm thick end plates are installed around the segment to form a whole. The spacing between the inner arc-shaped steel gusset plate and the circumferential ribs along the tunnel centerline is approximately 300mm, and the radial ribs are roughly evenly distributed at 5° intervals. (See also...) Figure 4 The end plate shown has grooves to form an enclosed water-stop groove, and a water-swellable rubber water-stop strip is installed inside the water-stop groove; this facilitates construction and installation and avoids the drawback of easy water leakage at the tongue and groove joint.

[0045] Construction method:

[0046] Standard block A2, standard block A3, adjacent block B1, capping block K1, and adjacent block C1 are equipped with lifting holes (which also serve as grouting holes) in their middle positions, allowing for individual lifting. S4 is equipped with a lifting hole; the portal frame segment and portal section segments S1+S2+S3+S4 can only be lifted after being bolted together as a whole. S4' is equipped with a lifting hole; the portal frame segment and portal section segments S1'+S2'+S3'+S4' can only be lifted after being bolted together as a whole. S1' and S1 are symmetrically arranged portal frame segments on two adjacent rings of segments.

[0047] Standard block A2, standard block A3, adjacent block B1, capping block K1, adjacent block C1, and special blocks S1+S2+S3+S4 form a segment ring; standard block A2, standard block A3, adjacent block B1, capping block K1, adjacent block C1, and special blocks S1'+S2'+S3'+S4' form another segment ring. Each segment is connected by four bolts, and the segment rings are connected longitudinally by ten bolts.

[0048] The steel pipe segments to be dismantled at the portal of the connecting passage are constructed by splicing three portal segments (S2+S3+S4 or S2'+S3'+S4') at a time, with a total of six portal segments at the portal. Symmetrical bolt holes are pre-drilled on the end plates at the joints of each portal segment for temporary connection and fixation during segment hoisting and assembly. When dismantling the portal segments, segment S4 can be the first segment to be removed, creating space for further dismantling of the remaining portal segments until all dismantling is complete.

Claims

1. A shield section connecting passage of a steel pipe segment structure reserving a portal, comprising two adjacent steel pipe segments fixed integrally within the range of a portal of a connecting passage, characterized in that, Each ring of steel pipe segment corresponds to include standard block A2 (1) connected in turn clockwise, standard block A3 (2), adjacent block B1 (3), capping block K1 (4), adjacent block C1 (5), special block S (6) is composed of a pipe segment ring; The central angle angle corresponding to the special block S is 72° and is arranged symmetrically on the horizontal axis of the pipe segment ring, the central angle angle corresponding to the standard block A2 is 72° and is arranged clockwise next to the lower edge of the special block S, the central angle angle corresponding to the standard block A3 is 72° and is arranged clockwise next to the standard block A2, the central angle angle corresponding to the adjacent block B1 is 68° and is arranged clockwise next to the standard block A3, the central angle angle corresponding to the adjacent block C1 is 68° and is arranged counterclockwise next to the upper edge of the special block S, and the central angle angle corresponding to the capping block K1 is 8° and is arranged in a wedge shape between the adjacent blocks B1 and C1. The special block S (6) includes a door frame pipe segment S1 (61), a door sub-block pipe segment S2 (62), a door sub-block pipe segment S3 (63), and a door sub-block pipe segment S4 (64). The door frame pipe segment S1 is in a half door frame shape, and the door sub-block pipe segments S2 (62), S4 (64), and S3 (63) are arranged in turn clockwise inside the half door frame. The door sub-block pipe segment S4 is a wedge-shaped pipe segment, and the adjacent edges of the door sub-block pipe segments S2, S3, and S4 are corresponding wedge-shaped inclined surfaces. The door frame pipe segments S1 of two rings of pipe segments are symmetrically arranged to form a whole door frame, and the door sub-block pipe segments S2, S3, and S4 arranged inside the half door frame of the door frame pipe segment S1 of two rings of pipe segments are symmetrically arranged side by side to form a door. Each pipe segment is a steel structure, mutually connected by bolts, with an arc steel plate on the outside, a steel plate on the inside, and a rib plate between the inside and the outside. The steel pipe segments have the same width and thickness as the reinforced concrete pipe segments outside the range of the connecting channel, and the circumferential rib plates (8) and the radial rib plates (9) of each steel pipe segment are aligned to ensure that the size of the tunnel side wall has no abrupt change. The included angle between the connecting surface of the door sub-block pipe segment S4 and the radial line is 14°.

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