Reinforcing structure of shield area with soft upper part and hard lower part

Abstract

The utility model relates to the field of shield tunneling machines, in particular to a reinforcing structure for a shield region with a soft upper part and a hard lower part, which adopts jet grouting piles for reinforcement. Cement grout is injected into a stratum through a high-pressure rotary jet grouting method to form a reinforcing body. Then micro steel pipe piles are constructed, the micro steel pipe piles are driven into the stratum, it is ensured that the bottoms of the micro steel pipe piles do not penetrate through the shield tunneling line, and the bottoms of the micro steel pipe piles and the shield tunneling line are in the same horizontal line; and then construction of a pre-stressed anchor rod is conducted, the high-strength steel strand is driven into the stratum from the tunnel through drilling, pre-stress is applied, and a pre-stressed anchor rod supporting structure is formed. And finally, construction of an earth surface reinforcing layer is conducted, cement mortar or other proper reinforcing materials are adopted for reinforcing the earth surface, the stability and the bearing capacity of a shield area with the soft upper portion and the hard lower portion can be effectively improved, and the risks of accidents such as excessive settlement and collapse in the shield tunnel construction process are reduced. And safe and smooth shield tunnel construction is guaranteed.

Description

Technical Field

[0001] This utility model relates to the field of tunnel boring machine technology, and in particular to a reinforcement structure for the shield tunneling area that is soft on top and hard on the bottom. Background Technology

[0002] Shield tunneling technology, especially earth pressure balance shield tunneling technology, has been widely used in large-scale underground engineering projects due to its advantages such as strong adaptability to geological formations, high level of information intelligence, safety and speed, and maintenance of harmony and unity with the surrounding environment. However, shield tunneling in the dredged sand layers of reclaimed land is a current challenge in subway construction projects. Because the dredged sand layers in reclaimed land contain a large number of medium to heavy liquefaction layers (medium-coarse sand) and weak layers (silt layers, silty clay layers), this stratum has high compressibility and low bearing capacity, which adversely affects the initiation and excavation of the shield. This is especially true during the construction of new tunnels (such as new subway tunnels), where close-range underpasses of existing tunnels (such as existing subway tunnels) are increasingly common. When close-range underpasses and sudden changes in local strata between soft and hard layers occur simultaneously, it is extremely detrimental to the control of the shield machine and the safety of the existing tunnel. For example, it can easily lead to excessive settlement and collapse of the existing tunnel and the ground, and pose risks to the safety of surrounding buildings and pipelines. Utility Model Content

[0003] Other features and advantages of this invention will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the invention. The objects and other advantages of this invention may be realized and obtained by means of the structures particularly pointed out in the description and other accompanying drawings.

[0004] The purpose of this invention is to overcome the above-mentioned shortcomings and provide a reinforcement structure for the shield tunnel area that is soft on top and hard on the bottom, so as to solve the existing problems.

[0005] To achieve the above objectives, the technical solution of this utility model is: a reinforcement structure for the shield tunnel area with a soft upper layer and a hard lower layer, including reinforcement with jet grouting piles. The jet grouting piles are set above the shield tunneling line and arranged in a matrix. Miniature steel pipe piles are installed between the jet grouting piles. Prestressed anchor rods are installed on both sides and bottom of the shield tunnel. The prestressed anchor rods are made of high-strength steel strands, and the length is determined according to the stratum conditions. The prestressed anchor rods are driven into the stratum through boreholes and prestress is applied to form a prestressed anchor rod support structure, which enhances the stability of the stratum.

[0006] In some embodiments, the miniature steel pipe pile is located at the bottom of the tunnel boring machine (TBM) tunneling line without penetrating the TBM tunneling line, and the bottom of the miniature steel pipe piles located on both sides is at the same horizontal line as the bottom of the TBM tunneling line.

[0007] In some embodiments, the miniature steel pipe pile uses a steel pipe with a diameter of 100-200 mm.

[0008] In some embodiments, a surface reinforcement layer with a thickness of 0.5-1.0 meters is provided on the ground surface at the location of the jet grouting pile.

[0009] In some embodiments, the outer wall of the steel pipe in the miniature steel pipe pile is provided with multiple through holes.

[0010] By adopting the above technical solution, the beneficial effects of this utility model are as follows: This utility model injects cement grout into the stratum using a high-pressure jet grouting method to form a reinforced body. Then, micro-steel pipe piles are constructed, driven into the stratum, ensuring that their bottoms do not penetrate the tunnel boring machine's (TBM) excavation path and are level with the bottom of the TBM's excavation path. Next, prestressed anchor bolts are constructed by drilling high-strength steel strands into the stratum from the tunnel and applying prestress to form a prestressed anchor bolt support structure. Finally, a surface reinforcement layer is constructed using cement mortar or other suitable reinforcement materials. This surface reinforcement effectively improves the stability and bearing capacity of the TBM-hardened area (soft upper layer, hard lower layer), reducing the risk of excessive settlement and collapse during TBM tunnel construction, and ensuring the safety and smooth progress of TBM tunnel construction.

[0011] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and are not intended to limit this disclosure.

[0012] Undoubtedly, such and other objects of this invention will become more apparent after the following detailed description of the preferred embodiments, which are illustrated in various accompanying drawings and illustrations.

[0013] To make the above and other objects, features and advantages of this utility model more apparent and understandable, one or more preferred embodiments are described below in detail with reference to the accompanying drawings. Attached Figure Description

[0014] The accompanying drawings are provided to further understand the present invention and form part of the specification. They are used together with the embodiments of the present invention to explain the present invention and do not constitute a limitation thereof.

[0015] In the accompanying drawings, the same parts use the same reference numerals, and the drawings are schematic and not necessarily drawn to actual scale.

[0016] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only one or more embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on such drawings without creative effort.

[0017] Figure 1 This is a schematic diagram of the reinforcement structure for the shield tunneling area with a soft upper layer and a hard lower layer, according to some embodiments of this utility model.

[0018] Figure 2 This is a schematic diagram of the surface layer structure in some embodiments of the present invention;

[0019] Figure 3 This is a schematic diagram of the steel pipe structure according to some embodiments of the present utility model;

[0020] Figure 4 This is a schematic diagram of the installation structure of prestressed anchor bolts according to some embodiments of this utility model.

[0021] Figure label:

[0022] 1. Jet grouting piles;

[0023] 2. Miniature steel pipe piles;

[0024] 21. Steel pipe; 22. Through hole;

[0025] 3. Shield tunneling route;

[0026] 4. Prestressed anchor bolts;

[0027] 5. Surface reinforcement layer. Detailed Implementation

[0028] To make the objectives, technical solutions, and advantages of this utility model clearer, the present utility model will be further described in detail below with reference to specific embodiments. It should be understood that the specific embodiments described herein are merely for explaining the present utility model and are not intended to limit the present utility model.

[0029] Furthermore, it should be understood in the description of this utility model that the terms "center," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0030] In this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," "joining," and "fixing" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral unit; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. However, specifying a direct connection indicates that the two main bodies at the connection point are not connected through a transitional structure, but are simply connected to form a whole through a connecting structure. For those skilled in the art, the specific meaning of the above terms in this utility model can be understood according to the specific circumstances.

[0031] In this utility model, unless otherwise expressly specified and limited, the first feature "on" or "below" the second feature may be in direct contact with the first and second features, or indirect contact through an intermediate medium. In the description of this specification, references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this utility model. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0032] The specific embodiments of this utility model are described below with reference to the accompanying drawings.

[0033] Reference Figure 1-4 The reinforcement structure for the shield tunnel area of ​​this utility model, which features a soft upper layer and a hard lower layer, includes jet grouting piles 1, micro steel pipe piles 2, prestressed anchor rods 4, and a surface reinforcement layer 5. The jet grouting piles 1 are installed above the shield tunneling line 3, arranged in a matrix to form a large-area reinforcement zone. The micro steel pipe piles 2 are located between the jet grouting piles 1, their bottoms not penetrating the shield tunneling line 3, and their bottoms being at the same horizontal level as the bottom of the shield tunneling line 3. The micro steel pipe piles 2 use steel pipes 21 with a diameter of 100-200 mm, and have multiple through holes 22 on their outer walls to allow cement grout to fully mix with the surrounding strata. The prestressed anchor rods 4 are installed on both sides and the bottom of the shield tunnel, using high-strength steel strands, with lengths determined according to the geological conditions. The prestressed anchor rods 4 are driven into the strata through boreholes and prestressed, forming a prestressed anchor rod support structure to enhance the stability of the strata. The surface reinforcement layer 5 is set on the ground surface at the location of the jet grouting pile 1, with a thickness of 0.5-1.0 meters. It is made of cement mortar or other suitable reinforcement materials to further improve the bearing capacity and stability of the ground surface.

[0034] During construction, the first step is to install jet grouting piles 1, injecting cement grout into the stratum using high-pressure jet grouting to form a reinforced body. Next, micro-steel pipe piles 2 are installed, driven into the ground, ensuring their bottoms do not penetrate the tunnel boring machine (TBM) tunneling line 3 and are level with the bottom of the TBM tunneling line 3. Following this, prestressed anchor bolts 4 are installed, drilling high-strength steel strands into the ground from the tunnel and applying prestress to form a prestressed anchor bolt support structure. Finally, the surface reinforcement layer 5 is constructed, using cement mortar or other suitable reinforcement materials to reinforce the surface.

[0035] Through the above-mentioned reinforcement structure and construction method, this utility model can effectively improve the stability and bearing capacity of the shield tunnel area with soft upper part and hard lower part, reduce the risk of accidents such as excessive settlement and collapse during shield tunnel construction, and ensure the safety and smooth progress of shield tunnel construction.

[0036] It should be understood that the embodiments disclosed herein are not limited to the specific processing steps or materials disclosed herein, but should be extended to equivalent substitutions of such features as understood by those skilled in the art. It should also be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting.

[0037] The term "embodiment" in this specification refers to a specific feature or characteristic described in connection with an embodiment that is included in at least one embodiment of the present invention. Therefore, phrases or "embodiments" appearing in various places throughout the specification do not necessarily refer to the same embodiment.

[0038] Furthermore, the described features or characteristics may be incorporated into one or more embodiments in any other suitable manner. In the above description, specific details, such as thickness, quantity, etc., are provided to provide a comprehensive understanding of embodiments of the present invention. However, those skilled in the art will understand that the present invention can be implemented without the aforementioned one or more specific details or may be implemented using other methods, components, materials, etc.

Claims

1. A reinforcement structure for a shield tunneling area with a soft upper layer and a hard lower layer, characterized in that, include: Jet grouting piles are used for reinforcement. These jet grouting piles are installed above the tunnel boring machine (TBM) excavation line and arranged in a matrix. Miniature steel pipe piles are installed between the jet grouting piles. Prestressed anchor rods are installed on both sides and bottom of the TBM tunnel. These prestressed anchor rods are made of high-strength steel strands, and their length is determined according to the geological conditions. The prestressed anchor rods are driven into the strata through boreholes and prestressed to form a prestressed anchor rod support structure, which enhances the stability of the strata.

2. The reinforcement structure for the shield tunneling area with a soft upper layer and a hard lower layer according to claim 1, characterized in that: The miniature steel pipe pile is located at the bottom of the tunnel boring machine (TBM) tunneling line without penetrating the TBM tunneling line. The bottom of the miniature steel pipe pile located on both sides is at the same level as the bottom of the TBM tunneling line.

3. The reinforcement structure for the shield tunneling area with a soft upper layer and a hard lower layer according to claim 1, characterized in that: The miniature steel pipe pile uses steel pipes with a diameter of 100-200 mm.

4. The reinforcement structure for the shield tunneling area with a soft upper layer and a hard lower layer according to claim 1, characterized in that: A surface reinforcement layer with a thickness of 0.5-1.0 meters is installed at the location of the jet grouting pile.

5. The reinforcement structure for the shield tunneling area with a soft upper layer and a hard lower layer according to claim 3, characterized in that: The outer wall of the steel pipe in this miniature steel pipe pile has multiple through holes.

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