A shield tunnel axial flexible connection seismic mechanism and seismic pipe joint

Abstract

The present invention provides an axially flexible seismic-resistant connection mechanism and a seismic-resistant pipe segment for a shield tunnel. The overall shape of the axially flexible seismic-resistant connection mechanism matches the axial arc-shaped bolt hole, and includes a metal ring, a flexible metal mesh, a steel strand, an anchoring clamp, a supporting clamp, a hydraulic jack, and a hydraulic controller. The shield tunnel flexible seismic-resistant connection pipe segment includes two left and right groups of pipe segments assembled into a ring, and the axially flexible seismic-resistant connection mechanism is installed as a whole in the axial arc-shaped bolt holes in the two adjacent left and right pipe segments; the axially flexible seismic-resistant connection mechanism is provided with multiple groups, and the multiple groups of axially flexible seismic-resistant connection mechanisms share a hydraulic controller. On the one hand, the present invention solves the problem that the connecting bolts are difficult to install due to the accumulation of axial errors during the installation of existing shield tunnel segments, and on the other hand, it can automatically perform flexible seismic resistance through vibration sensing.

Description

Technical Field

[0001] The invention provides an axial flexible connection anti-seismic mechanism and an anti-seismic pipe segment for use in a shield tunnel, belonging to the technical field of tunnel structures. Background Art

[0002] The shield method is a fully mechanized construction method in the underground excavation method. It pushes the shield machine into the ground, and uses the shield shell and segments to support the surrounding rock to prevent collapse into the tunnel. At the same time, a cutting device is used to excavate the soil in front of the excavation face, and the soil is transported out of the hole by the excavation machinery. The jack is used to pressurize and push forward at the rear, and precast concrete segments are assembled to form a mechanized construction method of the tunnel structure.

[0003] The segments of a shield tunnel are the primary components of shield construction and the innermost barrier of the tunnel, responsible for resisting soil pressure, groundwater pressure, and other special loads. Shield segments are the permanent lining structure of a shield tunnel. Their quality directly impacts the overall quality and safety of the tunnel, affecting its waterproofing and durability. Each segment is pre-designed based on the tunnel's planned diameter and orientation, then fabricated using molds. During the segment manufacturing process, various factors influence the segment's performance, leading to variations in the segment's shape. While these variations may not be significant in individual segments, they can accumulate and increase in axial direction as tunnel excavation and segment installation progress. This can especially affect joints, where misalignment can be visible to the naked eye. Under these conditions, workers face significant difficulty installing conventional bent bolts, requiring constant adjustment of their shape to accommodate misalignment. This negatively impacts both construction progress and the robustness of tunnel connections.

[0004] In addition, with the current in-depth development of engineering construction, the scale of development and construction of underground space structures continues to increase. From a geological structural analysis, underground tunnel projects in many parts of my country are located in earthquake-prone areas. The seismic safety performance design of underground engineering structures is particularly important. When using shield technology for tunnel construction, scientific seismic performance design and construction should be carried out to enhance the safety and stability of the tunnel. During construction, the stability of the foundation structure should be strengthened as much as possible, saturated sand foundations should be avoided, and the risk of earthquake liquefaction should be reduced. By adopting seismic joints or adding flexible joints between tunnel sections, reducing the overall length of the tunnel, and increasing the density between the soil and the tunnel lining, the seismic effect of the shield tunnel can be maximized. However, there are currently few reports on flexible seismic pipe sections in shield tunnels. Summary of the Invention

[0005] The present invention solves the deficiencies in the prior art and provides an axially flexible connection seismic-resistant mechanism and seismic-resistant pipe segment for a shield tunnel. On the one hand, it solves the problem of difficulty in installing connecting bolts due to the accumulation of axial errors during the installation of existing shield tunnel segments. On the other hand, it can automatically perform flexible seismic resistance through vibration sensing.

[0006] The technical solution adopted to achieve the above-mentioned purpose of the present invention is:

[0007] A shield tunnel axially flexible connection anti-seismic mechanism is installed in an axial arc-shaped bolt hole reserved in a shield tunnel segment. The overall shape of the axially flexible connection anti-seismic mechanism matches the axial arc-shaped bolt hole and includes the following parts:

[0008] The metal rings are provided with multiple pieces of the same shape. All the metal rings are stacked in sequence on the left and right to form an arc-shaped support structure that matches the shape and length of the axial arc-shaped bolt hole. A smooth arc-shaped channel is formed inside the arc-shaped support structure.

[0009] A flexible metal mesh is wrapped around the outside of the arc-shaped support structure to clamp and limit the arc-shaped support structure;

[0010] There are more than one steel strands, and the steel strands pass through the arc-shaped channel;

[0011] An anchoring clamp is provided at one end of the steel strand to anchor the steel strand at that end;

[0012] A supporting clamp is provided at the other end of the steel strand, and the steel strand passes through the supporting clamp;

[0013] The hydraulic jack is a through-type structure. The base of the hydraulic jack is placed against the support fixture. The steel strand passes through the hydraulic jack. The top of the hydraulic jack's piston rod is anchored to the steel strand through the anchor head. The steel strand is tightened by the extension of the hydraulic jack.

[0014] The hydraulic controller is connected to the hydraulic jack through the hydraulic oil circuit to control the extension and retraction of the hydraulic jack.

[0015] The metal ring piece has a circular shape and is a thin piece with unequal wall thickness. A groove serving as a mark is provided at the edge of the thickest part of the metal ring piece.

[0016] A mounting seat is provided on the side wall of the hydraulic jack, and the hydraulic jack is fixed on the shield tunnel segment through expansion bolts and the mounting seat.

[0017] A shield tunnel flexible connection seismic resistance pipe segment based on the above-mentioned axial flexible connection seismic resistance mechanism comprises two groups of left and right pipe segments assembled into a ring, axial arc bolt holes are evenly distributed on the pipe segment, and the positions of the axial arc bolt holes on the left and right pipe segments correspond to each other, an enlarged hole is provided at the position of the axial arc bolt hole located on the pipe segment connection surface, and an installation groove is provided at the position of the axial arc bolt hole located on the inner wall of the pipe segment; the axial flexible connection seismic resistance mechanism is integrally installed in the axial arc bolt holes in the two adjacent left and right pipe segments, and the anchoring clamp is located in the installation groove of the pipe segment on one side, and the support clamp and the hydraulic jack are provided. The top is located in the installation groove of the pipe section on the other side; the axial flexible connection anti-seismic mechanism is provided with multiple groups, and the number thereof is consistent with the distribution number of axial arc bolt holes. Multiple groups of axial flexible connection anti-seismic mechanisms share a hydraulic controller, which is located at the bottom of the shield tunnel and is connected to the power facilities in the shield tunnel; the hydraulic controller is connected to all the hydraulic jacks through the hydraulic oil circuit. Under normal circumstances, the hydraulic controller controls the jack to lift and tighten the steel strand to make the left and right pipe sections firmly connected; during earthquake resistance, the hydraulic controller controls the jack to retract and loosen the steel strand to provide clearance to the pipe sections on both sides for earthquake resistance.

[0018] The shield tunnel flexible connection seismic pipe section is also provided with an automatic seismic module, including a vibration sensor, a power supply, a central processing unit and a data storage device. The vibration sensor is arranged in the shield tunnel to collect external vibration data. The vibration sensor is connected to the central processing unit and transmits the collected vibration signal to the central processing unit after A / D conversion. The data storage device stores a vibration threshold. After the central processing unit compares the received vibration signal with the vibration threshold, it automatically sends an instruction to the hydraulic controller when the vibration threshold is exceeded, so that the hydraulic controller controls the jack to retract and thus loosens the steel strand.

[0019] The shield tunnel flexible connection seismic resistance pipe segments are distributed at intervals in the integral shield tunnel, and the distribution density is determined according to the manufacturing accuracy of the pipe segments and the overall seismic resistance requirements of the tunnel.

[0020] Compared with the prior art, the shield tunnel axial flexible connection anti-seismic mechanism and anti-seismic pipe segment provided by the present invention have the following advantages: 1. In the present invention, the traditional bent bolts are replaced with flexible steel strands in a breakthrough. Since the strong friction of the steel strands during the tensioning process may cause wear of the concrete in the pipe segment, the present invention further adopts a breakthrough metal ring. On the one hand, the metal ring can protect the concrete in the pipe segment, and on the other hand, it can also disperse the staggered distance between the left and right pipe segments. Through the cooperation of the metal ring and the enlarged hole, it can provide an arc channel that is as smooth as possible, so that the steel strands can pass through it smoothly, thereby facilitating the subsequent tensioning of the steel strands. Therefore, this mechanism can overcome the defect of the existing shield tunnel segments that is difficult to install bent bolts due to the accumulation of errors.

[0021] 2. In the present invention, a hydraulic jack is used to tension the steel strands, and after tensioning is completed, the hydraulic jack is not disassembled but is always fixedly mounted on the pipe segment, and no steel strand cutting or grouting operations are performed. In this way, when a relatively strong earthquake occurs, the hydraulic controller can be used to control the jack to retract, thereby loosening the steel strands, and then provide clearance to the pipe sections on both sides for earthquake resistance. In order to facilitate automated control, an automatic earthquake resistance module is also provided in the present invention. A vibration sensor is provided in the shield tunnel to collect external vibration data and transmit it to the central processing unit. The central processing unit compares the received vibration signal with the vibration threshold, and automatically sends a command to the hydraulic controller when the vibration threshold is exceeded, so that the hydraulic controller controls the jack to retract, thereby loosening the steel strands. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 A schematic diagram of the overall structure of the shield tunnel axial flexible connection anti-seismic mechanism provided by the present invention;

[0023] Figure 2 Schematic diagram of the structure of the metal ring;

[0024] Figure 3 A schematic diagram of the structure of a flexible connection seismic-resistant pipe segment for a shield tunnel provided by the present invention;

[0025] Figure 4 Schematic diagram of the structure of the axial arc bolt hole;

[0026] Figure 5 It is a connection diagram in staggered state;

[0027] Figure 6 This is the structural diagram of the automatic seismic resistance module;

[0028] In the figure: 1-axial arc bolt hole, 2-metal ring, 21-groove, 3-flexible metal mesh, 4-steel strand, 5-anchor clamp, 6-support clamp, 7-hydraulic jack, 71-mounting seat, 72-expansion bolt, 8-enlarged hole, 9-mounting slot. DETAILED DESCRIPTION

[0029] The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments, but the protection scope of the present invention is not limited to the following embodiments.

[0030] The overall structure of the shield tunnel axial flexible connection anti-seismic mechanism provided in this embodiment is as follows: Figure 1 As shown, in order to facilitate the display of its specific structure, Figure 1 Take a full section view. Figure 1 As shown, the metal ring sheet 2 is provided with multiple pieces of the same shape. All the metal ring sheets are stacked in sequence to form an arc-shaped support structure that matches the shape and length of the axial arc-shaped bolt hole. A smooth arc-shaped channel is formed inside the arc-shaped support structure. The single-piece structure of the metal ring sheet is as shown in FIG. Figure 2 As shown, its shape is circular, and the metal ring sheet is a thin sheet of unequal wall thickness, and a groove 21 is provided at the edge of its thickest part to serve as a mark. In the present invention, since it is necessary to stack and form an arc-shaped support structure that matches the axial arc-shaped bolt hole, the arc-shaped support structure needs to have a certain degree of curvature. Therefore, this purpose can only be achieved by setting the metal ring sheet as a thin sheet of unequal wall thickness. During the production and preparation process, since the wall thickness difference of the metal ring sheet is extremely small and difficult to distinguish with the naked eye, a groove mark is provided at the thickest part of the metal ring sheet to solve the problem of rapid assembly of the metal ring sheet during the preparation process. The flexible metal mesh 3 is wrapped around the outside of the arc-shaped support structure to clamp and limit the arc-shaped support structure; the flexible metal mesh is made of flexible wear-resistant metal material. On the one hand, it provides an initial limit to the arc-shaped support structure to prevent it from loosening. On the other hand, it is flexible and can be used for self-adjustment under staggered working conditions.

[0031] There are more than one steel strand 4, which passes through the arc-shaped channel. Usually, depending on the diameter of the shield tunnel and the diameter of the axial arc-shaped bolt hole, one or more steel strands can be provided. In this embodiment, one steel strand is provided. An anchoring clamp 5 is provided at one end of the steel strand to anchor the steel strand at that end. A supporting clamp 6 is provided at the other end of the steel strand, and the steel strand passes through the supporting clamp. Since no anchoring plate is provided in the supporting clamp, the steel strand is not anchored. The hydraulic jack 7 is a through-type structure. The base of the hydraulic jack is abutted against the supporting clamp. The steel strand passes through the hydraulic jack. The top of the piston rod of the hydraulic jack is anchored to the steel strand through the anchor head. The steel strand is tightened by the extension of the hydraulic jack. The hydraulic controller is connected to the hydraulic jack through the hydraulic oil circuit to control the extension and retraction of the hydraulic jack.

[0032] The structure of the flexible connection anti-seismic pipe segment of the shield tunnel provided in this embodiment is as follows: Figure 3 As shown in the figure, there are three pipe segments assembled into a ring. The two pipe segments on the right are the shield tunnel flexible connection seismic resistance pipe segments. Axial arc bolt holes 1 are evenly distributed on the pipe segments. The structure of the axial arc bolt holes is as follows: Figure 4 As shown, the positions of the axial arc bolt holes on the left and right pipe segments correspond to each other. Among the axial arc bolt holes provided on the pipe segments, an enlarged hole 8 is provided at the position located on the pipe segment connection surface, and an installation groove 9 is provided at the position of the axial arc bolt hole 1 located on the inner wall of the pipe segment.

[0033] The overall shape of the axial flexible connection anti-seismic mechanism is consistent with the axial arc bolt hole. The axial flexible connection anti-seismic mechanism is installed as a whole in the axial arc bolt holes in the two adjacent pipe sections on the left and right, and the anchoring clamp is located in the mounting groove 9 of the pipe section on one side, and the support clamp and the hydraulic jack are located in the mounting groove of the pipe section on the other side; a mounting seat 71 is provided on the side wall of the hydraulic jack, and the hydraulic jack is fixed in the mounting groove on the shield tunnel segment through the expansion bolt 72 and the mounting seat.

[0034] When the adjacent pipe sections are misaligned due to cumulative errors, such as Figure 5 As shown, the joints of the axial arc-shaped bolt holes on the left and right pipe segments are not in the same straight line. In order to solve the installation problem in this situation, the present invention has made a breakthrough in replacing the traditional bent bolts with flexible steel strands. Since the strong friction of the steel strands during the tensioning process may cause wear of the concrete in the pipe segment, the present invention has also made a breakthrough in using metal rings. On the one hand, the metal rings can protect the concrete in the pipe segment, and on the other hand, they can also disperse the staggered distance between the left and right pipe segments. Figure 5As shown, the cooperation between the metal ring and the enlarged hole can provide an arc-shaped channel that is as smooth as possible, so that the steel strand can pass through it smoothly, thereby facilitating the subsequent tensioning of the steel strand.

[0035] The axial flexible connection anti-seismic mechanism is provided with multiple groups, the number of which is consistent with the number of axial arc bolt holes. Figure 3 ( Figure 3 (Not all axially flexible connection seismic resistance mechanisms are shown; only the bottom three are shown.) Multiple axially flexible connection seismic resistance mechanisms share a common hydraulic controller, located at the bottom of the shield tunnel and connected to the power facilities within the shield tunnel. The hydraulic controller is connected to all hydraulic jacks via hydraulic oil circuits. Under normal conditions, the hydraulic controller controls the jacks to lift, thereby tightening the steel strands and securing the left and right pipe sections. During seismic events, the hydraulic controller controls the jacks to retract, loosening the steel strands and providing clearance for the left and right pipe sections to resist earthquakes.

[0036] The shield tunnel flexible connection anti-seismic pipe segment is also provided with an automatic anti-seismic module, such as Figure 6 As shown, it includes a vibration sensor, a power supply, a central processing unit and a data storage device, wherein the vibration sensor is set in the shield tunnel to collect external vibration data, the vibration sensor is connected to the central processing unit and transmits the collected vibration signal to the central processing unit after A / D conversion, the data storage device stores the vibration threshold, the central processing unit compares the received vibration signal with the vibration threshold, and automatically sends an instruction to the hydraulic controller when the vibration threshold is exceeded, so that the hydraulic controller controls the jack to retract and thus loosens the steel strand.

[0037] The distribution of flexible shield tunnel seismic-resistant pipe segments within the monolithic shield tunnel is determined by the segment manufacturing precision and the overall seismic resistance requirements of the tunnel. Generally speaking, for shield tunnels in high-seismic areas or shield tunnels with less precise segment manufacturing, a denser distribution can be used; otherwise, a sparser distribution can be used.

Claims

1. A shield tunnel axial flexible connection anti-seismic mechanism, installed in an axial arc-shaped bolt hole reserved in a shield tunnel segment, characterized by: The overall shape of the axial flexible connection anti-seismic mechanism is consistent with the axial arc-shaped bolt hole, and includes the following parts: The metal rings are provided with multiple pieces of the same shape. All the metal rings are stacked in sequence on the left and right to form an arc-shaped support structure that matches the shape and length of the axial arc-shaped bolt hole. A smooth arc-shaped channel is formed inside the arc-shaped support structure. A flexible metal mesh is wrapped around the outside of the arc-shaped support structure to clamp and limit the arc-shaped support structure; There are more than one steel strands, and the steel strands pass through the arc-shaped channel; An anchoring clamp is provided at one end of the steel strand to anchor the steel strand at that end; A supporting clamp is provided at the other end of the steel strand, and the steel strand passes through the supporting clamp; The hydraulic jack is a through-type structure. The base of the hydraulic jack is placed against the support fixture. The steel strand passes through the hydraulic jack. The top of the hydraulic jack's piston rod is anchored to the steel strand through the anchor head. The steel strand is tightened by the extension of the hydraulic jack. The hydraulic controller is connected to the hydraulic jack through the hydraulic oil circuit to control the extension and retraction of the hydraulic jack.

2. The shield tunnel axial flexible connection anti-seismic mechanism according to claim 1, characterized in that: The metal ring piece has a circular shape and is a thin piece with unequal wall thickness. A groove serving as a mark is provided at the edge of the thickest part of the metal ring piece.

3. The shield tunnel axial flexible connection anti-seismic mechanism according to claim 1, characterized in that: A mounting seat is provided on the side wall of the hydraulic jack, and the hydraulic jack is fixed on the shield tunnel segment through expansion bolts and the mounting seat.

4. A shield tunnel flexible connection seismic resistant pipe segment based on the axially flexible connection seismic resistant mechanism of claim 1, comprising two left and right pipe segments assembled into a ring, the pipe segment having axial arc-shaped bolt holes evenly distributed on the pipe segment, and the axial arc-shaped bolt holes on the left and right pipe segments corresponding to each other, characterized in that: An enlarged hole is provided at the position of the axial arc bolt hole on the pipe segment connection surface, and an installation groove is provided at the position of the axial arc bolt hole on the inner wall of the pipe segment; the axial flexible connection seismic resistance mechanism is installed as a whole in the axial arc bolt holes in the two adjacent pipe segments on the left and right, and the anchoring clamp is located in the installation groove of the pipe segment on one side, and the supporting clamp and the hydraulic jack are located in the installation groove of the pipe segment on the other side; the axial flexible connection seismic resistance mechanism is provided with multiple groups, and the number thereof is consistent with the number of distribution of the axial arc bolt holes. Multiple groups of axial flexible connection seismic resistance mechanisms share a hydraulic controller, which is located at the bottom of the shield tunnel and connected to the power facilities in the shield tunnel; the hydraulic controller is connected to all the hydraulic jacks through the hydraulic oil circuit. Under normal circumstances, the hydraulic controller controls the jack to lift and tighten the steel strand to make the left and right pipe segments firmly connected; during seismic resistance, the hydraulic controller controls the jack to retract and loosen the steel strand to provide clearance to the pipe segments on both sides for seismic resistance.

5. The shield tunnel flexible connection seismic resistant pipe segment according to claim 4 is characterized in that: The shield tunnel flexible connection seismic pipe section is also provided with an automatic seismic module, including a vibration sensor, a power supply, a central processing unit and a data storage device. The vibration sensor is arranged in the shield tunnel to collect external vibration data. The vibration sensor is connected to the central processing unit and transmits the collected vibration signal to the central processing unit after A / D conversion. The data storage device stores a vibration threshold. After the central processing unit compares the received vibration signal with the vibration threshold, it automatically sends an instruction to the hydraulic controller when the vibration threshold is exceeded, so that the hydraulic controller controls the jack to retract and thus loosens the steel strand.

6. The shield tunnel flexible connection seismic resistant pipe segment according to claim 4, characterized in that: The shield tunnel flexible connection seismic resistance pipe segments are distributed at intervals in the integral shield tunnel, and the distribution density is determined according to the manufacturing accuracy of the pipe segments and the overall seismic resistance requirements of the tunnel.

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