Cavern and end reinforcing structure for in-tunnel receiving of shield tunneling machine

Abstract

The utility model discloses a cavern and end reinforcing structure for receiving in a shield tunneling machine cavern, which comprises an anchor rod support, a primary support, a secondary lining, a double-liquid grouting reinforcing body and an end wall, the section of the cavern is in a curved wall type, the cavern comprises a vault, a side wall and an inverted arch, the anchor rod support adopts a mortar anchor rod, the length of the anchor rod support is determined to be 3-4m according to the grade of surrounding rock, and the anchor rod support is arranged in a quincunx shape; the primary support is a net spraying and steel arch, and the secondary lining is C35 reinforced concrete with the thickness of 40cm; according to shield tunnel receiving end soil reinforcement, deep hole sleeve valve pipe grouting is adopted, cement-water glass double-liquid slurry is adopted as slurry, the effective length of a reinforcement body is 15 m, the transverse reinforcement thickness is 2 m around the tunnel, the vertical reinforcement thickness is 5 m above the tunnel and 2 m below the tunnel, and a grouting blind area can be avoided by using the advantage of enlarging the section; a reinforced concrete end wall with the thickness of 60 cm is arranged at the butt joint position of the shield tunnel and the cavern, steel bars of the end wall are welded to a primary support steel frame, mortar anchor rods are arranged at the end in the mode of avoiding the excavation range of the shield tunneling machine, and the safety of receiving of the shield tunneling machine in the cavern is further improved.

Description

TECHNICAL FIELD

[0001] The utility model relates to a shield tunnel construction technical field especially relates to a chamber and end reinforcing structure for shield machine hole receiving. BACKGROUND

[0002] With the rapid development of urban rail transit, shield method has become one of the mainstream technologies of tunnel construction due to its high efficiency, safety and small impact on the surrounding environment. Shield receiving is a key link in the shield construction process. In traditional shield tunnel construction, a working well is set at the shield receiving end to complete the disassembly and hoisting of the shield. However, with the increasing complexity of urban ground environment, the location of the working well is limited by various factors such as dense buildings and complex underground pipelines, and in some cases it is impossible to set a receiving working well. Therefore, if the shield machine receiving operation can be completed in the mine method excavation chamber, the setting of the ground working well can be avoided, and the safety of the shield machine receiving can be ensured.

[0003] The key of the shield machine receiving technology in the mine method excavation chamber lies in the design of the receiving chamber and the end reinforcing structure, and the rationality of the design is directly related to the safety and construction efficiency of the shield receiving. The chamber structure design including cross-sectional shape and supporting structure will directly affect the stability of the chamber under complex geological conditions. End reinforcement is a key link in the design of the receiving chamber, and the existing reinforcement technologies such as grouting and pipe roof support have limited reinforcement effect in deep buried tunnels, and may cause risks such as water inrush, sand inrush and collapse when breaking the portal. Therefore, in the shield machine receiving in the mine method excavation chamber, it is urgent to develop a chamber structure that can improve the stability of the chamber and an end reinforcing structure that can improve the strength of the end soil to ensure the safe receiving of the shield. SUMMARY

[0004] The utility model aims at solving the shortcomings in the prior art and provides a chamber and end reinforcing structure for shield machine hole receiving, which is suitable for III or IV surrounding rock sections. The structure improves the stability of the mine method excavation shield machine receiving chamber and the strength of the receiving end soil, and ensures the safe receiving of the shield machine.

[0005] To achieve the above-mentioned purpose, the utility model adopts the following technical scheme:

[0006] A chamber and end reinforcing structure for shield machine hole receiving, comprising anchor rod support, primary support, secondary lining, double-liquid grouting reinforcement body and end wall, characterized in that the shield machine is received underground by the mine method excavation receiving chamber, the cross-sectional shape of the chamber is curved wall type, composed of vault, side wall and inverted arch, and the vault and side wall are divided by the arch part 140°.

[0007] Preferably, the anchor rod support adopts mortar anchor rod, the support range is arch top and side wall, the anchor rod material is HPB400, the mortar strength is not less than M20, the anchor rod length can be 3-4m according to the surrounding rock grade, the plum blossom shape is arranged, and the ring longitudinal spacing is 1.2*1.2m.

[0008] Preferably, the initial support adopts the support form of net spraying + steel arch, sprays C25 concrete, adopts a wet spraying process, the steel mesh adopts HPB300 steel with a diameter of 6mm, the mesh size is 250*250mm, the steel mesh sprayed concrete protection layer thickness is not less than 3cm, the steel arch uses G20b type steel frame, and the section steel is bent.

[0009] Preferably, the arch top, side wall and inverted arch sprayed concrete design thickness is 27cm, the steel frame is erected after spraying 4cm of concrete on the excavation surface, and then sprayed to the design thickness, the gap between the secondary lining and the secondary lining is backfilled with the same grade concrete, the secondary lining is C35 reinforced concrete, and the thickness is 40cm.

[0010] Preferably, the double-liquid grouting reinforcement body adopts deep hole sleeve valve pipe grouting, the slurry adopts cement-water glass double-liquid slurry, the effective length of the reinforcement body is 15m, the horizontal reinforcement thickness is 2m around the tunnel, and the vertical reinforcement thickness is 5m above the tunnel and 2m below the tunnel.

[0011] Preferably, the end wall is arranged at the butt joint of the shield tunnel and the chamber, is a reinforced concrete structure, has a thickness of 60cm, the end wall steel bars are welded with the initial support steel frame, and anchor rod support is arranged at the end head to avoid the excavation range of the shield machine, and the spacing is 1.0*1.0m.

[0012] Compared with the prior art, the utility model has the advantages that:

[0013] (1) the chamber cross section shape is curved wall type, the arch top and the side wall are smoothly transitioned, the stress distribution optimization performance is good, the structural bearing capacity and the overall stability are high, and can be applicable to complex geological conditions;

[0014] (2) the chamber both sides and the arch top area are prearranged with operation redundancy space, can adapt to hoisting equipment installation demand, provides operation space for efficient disassembly, hoisting and transfer after receiving the shield machine, improves the underground disassembly and hoisting efficiency of the shield machine;

[0015] (3) the end head soil body reinforcement adopts deep hole sleeve valve pipe grouting, the slurry adopts cement-water glass double-liquid slurry, can add the setting time and the injectability of the slurry according to the stratum condition, avoids the grouting blind area by utilizing the enlarged section advantage, and prevents the end head from gushing and collapsing;

[0016] (4) The end wall steel bar is welded with the primary support steel frame, and the mortar anchor rod is arranged at the end to avoid the shield machine excavation range, and the safety of the underground shield machine receiving is further improved. BRIEF DESCRIPTION OF DRAWINGS

[0017] In order to more specifically and intuitively illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed to be used in the embodiments or the prior art description will be briefly introduced below.

[0018] Fig. 1 A schematic diagram of a chamber structure is provided for the utility model;

[0019] Fig. 2 A schematic diagram of an end reinforcement structure is provided for the utility model;

[0020] Fig. 3 A schematic diagram of end anchor rod reinforcement is provided for the utility model.

[0021] In the drawing: 1-anchor rod support, 2-primary support, 3-secondary lining, 4-arch top, 5-side wall, 6-inverted arch, 7-double liquid grouting reinforcement body, 8-end wall, 9-shield tunnel. DETAILED DESCRIPTION

[0022] The technical solutions in the embodiments of the utility model will be clearly and completely described below in combination with the drawings in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, rather than all the embodiments.

[0023] REFERENCE Figs. 1-3 A chamber and end reinforcement structure for shield machine underground receiving, comprising an anchor rod support 1, a primary support 2, a secondary lining 3, a double liquid grouting reinforcement body 7, and an end wall 8, characterized in that the underground receiving chamber is realized by a mine method, the chamber cross section shape is a curved wall type, composed of an arch top 4, a side wall 5, and an inverted arch 6, and the arch top 4 and the side wall 5 are divided by an arch part 140°.

[0024] In the embodiment, the anchor rod support 1 adopts a mortar anchor rod, the support range is the arch top 4 and the side wall 5, the anchor rod material is HPB400, the mortar strength is not less than M20, the anchor rod length can be determined as 3-4m according to the surrounding rock grade, and the anchor rod is arranged in a plum blossom shape with a ring longitudinal distance of 1.2x1.2m.

[0025] In the embodiment, the primary support 2 adopts a support form of net spraying+steel arch support, sprays C25 concrete, adopts a wet spraying process, the steel mesh adopts HPB300 steel with a diameter of 6mm, the mesh size is 250x250mm, the steel mesh sprayed concrete protection layer thickness is not less than 3cm, the steel arch support uses a G20b type steel frame, and the section steel is bent into an I-shaped steel.

[0026] The primary support 2 is provided with a full ring of 20b type steel frames with a spacing of 100 cm, and the spacing of the steel frames is appropriately increased in soft and broken sections, a φ42 lock foot anchor pipe is arranged at the arch foot and wall foot position, the wall thickness is 3.5 mm, two steel pipes are arranged at each position, and the length of each steel pipe is 4.0 m, longitudinal connecting ribs are arranged between the steel frames, a φ22 HRB400 steel rib is used, the circumferential spacing is 1.2 m, three positioning steel ribs are arranged in each steel frame unit, the steel ribs are uniformly arranged on the left and right sides, the length of each steel rib is 1 m, and the steel ribs are welded with the steel frame.

[0027] The design thickness of the arch crown 4, the side wall 5 and the inverted arch 6 is 27 cm, the steel frame is erected after the initial spraying of 4 cm of concrete on the excavation surface, and then the concrete is sprayed to the design thickness, the gap between the sprayed support surface and the secondary lining is backfilled with the same grade concrete of the secondary lining, the secondary lining 3 is C35 reinforced concrete with a thickness of 40 cm.

[0028] In the embodiment, the double-liquid grouting reinforcement body 7 is grouted by using a deep-hole sleeve valve pipe, a cement-sodium silicate double-liquid slurry is used as the slurry, the volume ratio is 1:1, an additive for adjusting the setting time and the injectability of the slurry can be added according to the stratum condition, the effective length of the reinforcement body is 15 m, the lateral reinforcement thickness is 2 m around the tunnel, and the vertical reinforcement thickness is 5 m above the tunnel and 2 m below the tunnel.

[0029] In the embodiment, the end wall 8 is arranged at the joint between the shield tunnel 9 and the chamber, is a reinforced concrete structure with a thickness of 60 cm, the steel rib of the end wall 8 is welded with the primary support steel frame, and the anchor rod support 1 is arranged at the end to avoid the excavation range of the shield machine with a spacing of 1.0*1.0 m.

[0030] The above merely describes a preferred specific implementation manner of the utility model, but the protection scope of the utility model is not limited to this, any skilled person in the technical field according to the technical scheme and the utility model concept of the utility model within the technical range disclosed by the utility model can make equivalent replacement or change, and all should be covered in the protection scope of the utility model.

Claims

1. A chamber and end reinforcement structure for shield tunneling machine in-hole reception, comprising an anchor rod support (1), a primary support (2), a secondary lining (3), a double-liquid grouting reinforcement body (7), and an end wall (8), characterized in that, The shield machine receives the underground chamber by the mine method and the chamber section shape is a curved wall type, which is composed of a vault (4), a side wall (5) and an inverted arch (6), and the vault (4) and the side wall (5) are divided by the arch part 140°.

2. A chamber and terminal reinforcement structure for in-situ receiving of a tunnel boring machine according to claim 1, characterised in that, The anchor rod support (1) adopts a mortar anchor rod, the support range is the vault (4) and the side wall (5), the anchor rod material is HPB400, the mortar strength is not less than M20, the anchor rod length can be 3-4m according to the surrounding rock grade, and the anchor rod is arranged in a plum blossom shape.

3. The chamber and end reinforcement structure for in-hole receiving of a tunneling machine according to claim 1, characterized in that, The primary support (2) adopts a support form of a net spray + a steel arch, sprays C25 concrete, adopts a wet spray process, the steel mesh adopts HPB300 steel with a diameter of 6mm, the grid size is 250*250mm, the steel mesh spray concrete protection layer thickness is not less than 3cm, the steel arch uses a G20b type steel frame, and the section steel is bent into an I-shaped steel.

4. The chamber and end reinforcement structure for in-hole reception of a tunneling machine of claim 1, wherein, The vault (4), the side wall (5) and the inverted arch (6) spray concrete with a design thickness of 27cm, the steel frame is erected after the initial spray of 4cm of concrete on the excavation surface, and then is re-sprayed to the design thickness, the gap between the re-sprayed support surface and the secondary lining (3) is backfilled with the same grade concrete of the secondary lining, the secondary lining (3) is C35 reinforced concrete with a thickness of 40cm.

5. The chamber and end reinforcement structure for in-hole receiving of a tunneling machine according to claim 1, wherein The double-liquid grouting reinforcement body (7) adopts deep hole sleeve valve pipe grouting, the slurry adopts cement-sodium silicate double-liquid slurry, the effective length of the reinforcement body is 15m, the horizontal reinforcement thickness is 2m around the tunnel, and the vertical reinforcement thickness is 5m above the tunnel and 2m below the tunnel.

6. The chamber and spigot reinforcement structure for in-chamber receiving of a tunneling machine according to claim 1, wherein, The end wall (8) is arranged at the joint of the shield tunnel (9) and the chamber, is a reinforced concrete structure with a thickness of 60cm, the end wall (8) steel bars are welded with the primary support steel frame, and the anchor rod support (1) is arranged at the end to avoid the shield machine excavation range with a spacing of 1.0*1.0m.

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