A suspension bridge anchor structure integrating tunnel and anchor and its construction method

Abstract

The present invention discloses a suspension bridge anchor structure with a tunnel and anchor integrated therein and a construction method thereof, comprising an anchor body that wraps around a mainline tunnel, wherein the anchor body and the mainline tunnel form an integral structure. The present invention excavates an existing or newly established mainline tunnel and casts the anchor body, so that the anchor body and the mainline tunnel form an integral whole. This avoids the need for excessive anchor depth if the surrounding rock mass around the tunnel anchor is poor, and also avoids the problem of a small clearance distance between the structure and the mainline tunnel. In addition, the anchor body and the mainline tunnel form an integral whole, and the anchor body is equivalent to a gravity anchor block, which is not restricted by terrain conditions. The present invention combines the respective advantages of gravity anchors and tunnel anchors, and does not need to consider the influence of factors such as surrounding rock conditions and whether there is a mainline tunnel, thereby increasing the scope of use of suspension bridges.

Description

Technical Field

[0001] The present invention relates to the technical field of bridge construction, and in particular to a tunnel-anchor integrated suspension bridge anchor structure and a construction method thereof. Background Art

[0002] Existing large-span bridges often use suspension bridge structures. Suspension bridges are the main form of large-span bridges and are particularly suitable for large-span and extra-large-span highway bridges. The main load-bearing components of a typical suspension bridge are anchored to anchors. There are two traditional anchor structures: gravity anchors. This type of anchor relies on the huge deadweight of the anchor to resist the vertical component of the main cable, while the horizontal component is handled by friction or embedding between the anchor and the foundation. Due to the large size of the gravity anchor, it requires certain terrain conditions to be used, limiting its scope of application. The second type of anchor structure is the tunnel anchor. The tunnel anchor uses the anchor plug and the surrounding rock to form a force-bearing entity to jointly resist the tension of the main cable. The tunnel anchor has very high requirements for the surrounding rock conditions. In addition, during the application of the tunnel anchor, if the suspension bridge connects the tunnel, the distance between the tunnel constructed by the tunnel anchor and the main tunnel is relatively close, resulting in the deterioration of the surrounding rock around the main line tunnel. The tunnel anchor and the main line tunnel form a structural "small clear distance" tunnel, which is not conducive to the structural safety of the main line tunnel. Summary of the Invention

[0003] The purpose of the present invention is to provide a suspension bridge anchor structure with a tunnel-anchor integration and a construction method thereof, so as to solve the situation where gravity anchor blocks cannot be set up when there are no suitable terrain conditions, and when the surrounding rock conditions are poor and there is a main line tunnel, and tunnel anchors cannot be set up. By redesigning the anchor structure, the suspension bridge is not affected by the terrain conditions, surrounding rock conditions, and main line tunnel, thereby improving the scope of use of the suspension bridge.

[0004] The present invention is achieved through the following technical solutions:

[0005] A tunnel-anchor integrated suspension bridge anchor structure comprises an anchor body wrapping a main line tunnel, wherein the anchor body and the main line tunnel form an integral structure.

[0006] In view of the limitations of the existing anchor structure of suspension bridges, the use of suspension bridges is restricted by factors such as terrain conditions and surrounding rock conditions. The present invention provides a tunnel-anchor integrated suspension bridge anchor structure, including an anchor body on the main line tunnel, wherein the anchor body and the main line tunnel form an integral structure; during use, the anchor body and the main line tunnel form an integral structure, avoiding the defects of the existing anchor structure and increasing the scope of use of the suspension bridge; the anchor body in the present invention combines the advantages of a gravity anchor block and a tunnel anchor, the anchor body is integrated with the main line tunnel, and the anchor body fills the entire anchor body tunnel. The anchor body itself has a huge deadweight, and there is no need to consider the limitations of terrain conditions. Because the anchor body is integrated with the main line tunnel, the contact area between the anchor body and the surrounding rock is large, which can solve the problem of poor surrounding rock mass around the anchor body tunnel without taking measures to increase the anchor depth, and there is no problem of small clearance between the structure and the main line tunnel.

[0007] Furthermore, the anchor body includes an upper anchor body and a lower anchor body, and the cross-sections of the upper anchor body and the lower anchor body are both trapezoidal. The use of the trapezoidal structure can create a similar locking fit relationship between the surrounding rock and the anchor body, which is equivalent to a "clamping effect" and improves the firmness of the connection between the anchor body and the surrounding rock.

[0008] Furthermore, the trapezoidal shape includes a small end and a large end, and the small ends of the upper anchor body and the lower anchor body are close to the main line tunnel, which is more conducive to forming a "clamping effect" between the upper anchor body and the lower anchor body and the surrounding rock around the anchor body, thereby achieving the firmness of the anchor body and maintaining the stability of the anchor structure when the surrounding rock mass is poor, without adopting measures such as excessive anchor depth.

[0009] Furthermore, it also includes a plurality of saddle chambers arranged on the anchor body, and the saddle chambers are used to accommodate a large number of loose saddles.

[0010] Furthermore, it also includes several anchoring systems arranged on the anchor body, the anchoring systems are located in the saddle chamber, the anchoring systems adopt a prestressed steel beam anchoring structure, and the large pulling force is transmitted to the anchor body through the anchoring system.

[0011] Furthermore, the anchor body has a cylindrical structure, which enables the anchor body to have a huge deadweight and to firmly hold the suspension bridge.

[0012] Furthermore, it also includes a number of system anchor rods arranged at the connection between the anchor body and the surrounding rock. The purpose of arranging the system anchor rods around the anchor body is to strengthen the connection between the anchor body and the surrounding rock. At the same time, the anchor rod holes are used to complete the grouting of the anchor body surrounding rock, thereby improving the integrity of the surrounding rock and the joint force-bearing capacity of the anchor body.

[0013] The present invention also provides a construction method for a tunnel-anchor integrated suspension bridge anchor structure, comprising the following steps:

[0014] S1. After determining the position of the anchor body on the main line tunnel, expand the anchor body tunnel;

[0015] S2. Casting and sealing the anchor body tunnel to form the anchor body;

[0016] S3. Set up a saddle chamber and anchoring system on the anchor body;

[0017] S4. Set up system anchor rods at the connection between the anchor body and the surrounding rock.

[0018] In step S, the main line tunnel is excavated 5m on the left and right sides and 10m on the top and bottom, and the excavation shape is trapezoidal.

[0019] In step S, C40 polypropylene fiber anti-seepage concrete is used for pouring and sealing to form an anchor body.

[0020] The present invention has the following beneficial effects:

[0021] This invention excavates an existing or newly constructed mainline tunnel and casts the anchor body, forming a single unit with the mainline tunnel. This avoids the need for excessive anchor depths when the surrounding rock mass around the tunnel anchor is poor, and also avoids the problem of small structural clearances with the mainline tunnel. Furthermore, the anchor body forms a single unit with the mainline tunnel, acting as a gravity anchor block, and is not restricted by topographical conditions. Combining the advantages of both gravity anchors and tunnel anchors, this invention expands the scope of application of suspension bridges without considering factors such as surrounding rock conditions and the presence of a mainline tunnel. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The drawings described herein are used to provide a further understanding of the embodiments of the present invention, constitute a part of this application, and do not constitute a limitation of the embodiments of the present invention. In the drawings:

[0023] Figure 1 Schematic diagram of the anchor structure of a specific embodiment of the present invention.

[0024] Figure 2 This is a schematic diagram of anchor installation according to a specific embodiment of the present invention.

[0025] Reference numerals and corresponding component names: 1-main line tunnel, 2-anchor body, 201-upper anchor body, 202-lower anchor body, 3-system anchor rod, 4-saddle. DETAILED DESCRIPTION

[0026] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with examples and drawings. The exemplary embodiments of the present invention and their descriptions are only used to explain the present invention and are not intended to limit the present invention.

[0027] Example 1:

[0028] like Figure 1 and2 As shown, a tunnel-anchor integrated suspension bridge anchor structure includes an anchor body 2 that wraps the main line tunnel 1, and the anchor body 2 and the main line tunnel 1 form an integral structure; because the anchor body 2 and the main line tunnel 1 form an integral whole, the anchor body 2 and the main line tunnel 1 as a whole act as a gravity anchor block, and the large tensile force is resisted by the gravity of the anchor block 2 itself and the friction between the anchor block 2 and the surrounding rock. The anchor body 2 is wrapped in the surrounding surrounding rock, the contact area between the anchor body 2 and the surrounding rock is large, the force-bearing capacity is good, and the integrity of the anchor body 2 and the surrounding rock is high.

[0029] Example 2:

[0030] like Figure 1 As shown, this example is obtained by making further restrictions on the basis of Example 1: the anchor body 2 includes an upper anchor body 201 and a lower anchor body 202, and the cross-sections of the upper anchor body 201 and the lower anchor body 202 are both trapezoidal; the trapezoidal shape includes a small end and a large end, and the small ends of the upper anchor body 201 and the lower anchor body 202 are both close to the main line tunnel, and the positional relationship between the upper anchor body 201 and the lower anchor body 202 and the main line tunnel 1 forms a "clamping effect", which refers to the effect of the anchor block 2 and the surrounding rock being stuck during the vertical upward movement of the anchor block 2, which can improve the stability of the connection between the anchor body 2 and the surrounding rock.

[0031] It also includes several saddle chambers arranged on the anchor body 2. The upper anchor body 201 and the lower anchor body 202 have the same number of saddle chambers. In this embodiment, the number of saddle chambers is 2, and the number of saddle chambers of the upper anchor body 201 and the lower anchor body 202 is 1. The saddle chamber is a collection of several anchoring systems.

[0032] The anchor body 2 also includes several anchoring systems located within the saddle chamber. In this embodiment, these anchoring systems are cable saddles, which connect to the loose saddles of the large anchor, transferring the tensile stress of the large anchor to the anchor body 2. The cable saddles on the upper anchor body 201 and the lower anchor body 202 are arranged in a regular pattern, with the number of saddles determined according to actual needs. The cable saddles on the upper anchor body 201 and the lower anchor body 202 are symmetrical with each other about the mainline tunnel 1, which helps evenly distribute the force of the loose saddles of the large anchor on the anchor body 2.

[0033] Furthermore, the anchor body 2 has a cylindrical structure. The upper anchor body 201 and the lower anchor body 202 are both trapezoidal columns. The anchor body 2 is composed of two trapezoidal columns. In this embodiment, the anchor body 2 is formed in one step.

[0034] A number of system anchor rods 3 are arranged at the connection between the anchor body 2 and the surrounding rock. The system anchor rods 3 are evenly distributed. The connection between the anchor body and the surrounding rock is strengthened by the system anchor rods 3. At the same time, the anchor body surrounding rock is grouted using the anchor rod holes to improve the integrity of the surrounding rock and the joint stress bearing capacity of the anchor body.

[0035] Example 3:

[0036] This embodiment, based on Embodiments 1 and 2, provides a construction method for a suspension bridge anchor structure with a tunnel-anchor integration, comprising the following steps:

[0037] S1. After determining the position of the anchor body on the main line tunnel, expand the anchor body 2 tunnel;

[0038] S2. Cast and seal the anchor body tunnel to form anchor body 2. Conventional lining support is adopted for the main line tunnel 1 in the expanded excavation section.

[0039] S3. Setting a saddle chamber and anchoring system on the anchor body 2;

[0040] S4. Install the system anchor rod 3 at the connection between the anchor body 2 and the surrounding rock, and use the anchor rod hole to complete the grouting of the surrounding rock of the anchor body 2.

[0041] Furthermore, in step S1, the main line tunnel 1 is excavated 5m on the left and right sides and 10m on the top and bottom. The excavation shape is trapezoidal, so that the anchor body 2 tunnel forms a "clamping effect" with the surrounding rock.

[0042] Furthermore, in step S2, C40 polypropylene fiber anti-seepage concrete is used for pouring and sealing to form the anchor body 2.

[0043] The specific implementation methods described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific implementation method of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A construction method for a tunnel-anchor integrated suspension bridge anchor structure, characterized in that: The tunnel-anchor integrated suspension bridge anchor structure comprises an anchor body (2) wrapping a main line tunnel (1), wherein the anchor body (2) and the main line tunnel (1) form an integral structure; The anchor body (2) comprises an upper anchor body (201) and a lower anchor body (202), and the cross-sections of the upper anchor body (201) and the lower anchor body (202) are both trapezoidal; The trapezoidal shape includes a small end and a large end, and the small ends of the upper anchor body (201) and the lower anchor body (202) are both close to the main line tunnel; The construction method includes the following steps: S1. After determining the position of the anchor body (2) on the main line tunnel (1), the main line tunnel (1) is excavated 5 m on the left and right sides and 10 m on the top and bottom sides, with the excavation shape being trapezoidal, to form an anchor body (2) tunnel for casting the anchor body (2); S2, pouring and sealing the anchor body (2) tunnel to form the anchor body (2) outside the main line tunnel (1); S3, arranging a saddle chamber and an anchoring system on the anchor body (2), wherein the anchoring system is a cable saddle, which is connected to the loose saddle of the large saddle through the cable saddle, so as to realize the transmission of the tensile stress of the large saddle to the anchor body (2); S4. Install the system anchor rod (3) at the connection between the anchor body (2) and the surrounding rock.

2. The construction method of a tunnel-anchor integrated suspension bridge anchor structure according to claim 1, characterized in that: In step S2, C40 polypropylene fiber anti-seepage concrete is used for pouring and sealing to form an anchor body (2).

3. The construction method of a tunnel-anchor integrated suspension bridge anchor structure according to claim 1, characterized in that: It also includes a plurality of saddle chambers arranged on the anchor body (2).

4. The construction method of a tunnel-anchor integrated suspension bridge anchor structure according to claim 1, characterized in that: It also includes several anchoring systems arranged on the anchor body (2), and the anchoring systems are located in the saddle chamber.

5. The construction method of a tunnel-anchor integrated suspension bridge anchor structure according to claim 1, characterized in that: The anchor body (2) has a cylindrical structure.

6. The construction method of a tunnel-anchor integrated suspension bridge anchor structure according to any one of claims 1 to 5, characterized in that: It also includes a plurality of system anchor rods (3) arranged at the connection between the anchor body (2) and the surrounding rock.

Images