Adjustable forced centering support for circular tunnel traverse survey

Abstract

The invention relates to the technical field of underground engineering survey, and provides an adjustable forced centering support for circular tunnel traverse survey, which comprises a triangular tray base, a screw assembly, a connecting centering rod and a prism base. The tray base is made of a steel plate, threaded holes are distributed in three corners of the tray base respectively, two threaded holes are vertically provided with adjusting screws with conical tips, and the other threaded hole is vertically connected with a conical centering rod. The base is arranged on the tray base and supports the prism base with the level bubble. Wherein the adjusting screw rod is operated through a top screw rod handle, and the bottom cone of the centering rod is connected to abut against a measuring point; the tray base is hollow, so that the weight is reduced. Annular scale marks are additionally arranged on the top of the base, and the tip of the auxiliary centering rod is aligned with the center of the prism. The method can reduce the wire measurement error, improve the tunneling construction precision and reduce the construction cost.

Description

Technical Field

[0001] The invention relates to the technical field of underground engineering measurement, in particular to an adjustable forced centering bracket for circular tunnel conductor measurement. Background Art

[0002] In shield and TBM construction, with the increasing number of domestic water conservancy and hydropower, highway, and urban subway construction projects using shield and TBM construction, the conditions within the shield and TBM construction tunnels are limited. The layout of the battery car tracks, air, water, and pipelines, the shield mud and water system inlet and outlet pipes, and the layout of the tunnel walkway slabs all occupy a large part of the tunnel space. This partially obstructs the layout of the measurement points, causing corresponding difficulties for the surveyors during the wire measurement and wire control network review, and also has a local impact on the surveyors' operation. Therefore, the survey operators choose to place the measurement control points in the tunnel at effective corresponding positions. If the measurement control points are placed at the center bottom of the tunnel, there will be too much mud and water in the tunnel, and the measurement control points will be covered by the mud and water from the segment flushing. The surveyors will have many difficulties in finding and cleaning the mud at the points, which also takes up a lot of manpower, material resources, and time. In addition, some shield tail grease will remain on the surface of the segment during the segment flushing process, which will cause corresponding difficulties for the surveyors who are setting up the front and rear sight targets.

[0003] The installation of front and rear sight targets is performed by aligning and leveling the eyepieces with control points embedded within the tunnel. The measurement control points are located at corresponding locations on the drainage pipelines below the segment waistline. However, due to the circular shape of the segments, the resulting height difference is significant, making it difficult for surveyors to arrange the support points for the instruments and front and rear sight target tripods in a stable position. It also makes it difficult for surveyors to operate the instruments and front and rear sight targets and to center and level them. Furthermore, a significant amount of time is required to adjust the measurement tripods and select measurement positions. Furthermore, even more time is spent setting up stations and centering and leveling the front and rear sight targets, delaying the measurement of the guide control points and the re-measurement of the control network. This results in delays in the control of the shield machine and TBM excavation guidance system, impacting shield and TBM excavation operations. The long hours spent setting up stations and blindly centering and leveling the front and rear sight targets by surveyors lead to large measurement errors, reducing the efficiency of precision control during excavation, and increasing construction costs.

[0004] Therefore, the present invention proposes an adjustable forced centering bracket for circular tunnel conductor measurement. Summary of the Invention

[0005] The object of the present invention is to provide an adjustable forced centering bracket for circular tunnel conductor measurement, so as to reduce measurement errors, improve excavation construction accuracy and reduce construction costs.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions: An adjustable forced centering bracket for circular tunnel conductor measurement includes: a tray base, a screw, a connecting centering rod, a prism base, a prism, and a base; the tray base is a triangular frame structure with a through groove inside, and a threaded hole is respectively provided on the triangle of the tray base, two of which are respectively sleeved with a screw, and the remaining threaded hole is sleeved with a connecting centering rod, and the screw and the connecting centering rod are both perpendicular to the horizontal plane; the base is provided above the connecting threaded hole of the tray base connecting to the centering rod, and the center of the base is provided with the same threaded hole as the tray base, the prism base is placed above the base, and the prism is mounted on the prism base.

[0007] Preferably, a screw handle is provided at the top of the screw, and the screw handle is a hexagonal prism.

[0008] Preferably, the bottom of the screw is conical.

[0009] Preferably, the bottom of the connecting centering rod is conical, and the top of the connecting centering rod is a section of thread.

[0010] Preferably, a circular level bubble and a level tube bubble are provided on the prism base.

[0011] Preferably, a plurality of annular scale lines are provided on the top of the base.

[0012] The present invention discloses an adjustable forced centering bracket for circular tunnel conductor measurement, which has the following beneficial effects.

[0013] The present invention includes a triangular tray base, a screw assembly, a connecting centering rod and a prism base. The tray base is made of steel plate, with threaded holes distributed in a triangle. Two threaded holes are vertically installed with adjusting screws with tapered tips, and the other threaded hole is vertically connected to the tapered centering rod; the base is provided on the tray base to support the prism base with a level bubble. The adjusting screw is operated by the top screw handle to connect the bottom cone of the centering rod to the measuring point; the hollow design inside the tray base reduces weight. An annular scale line is added to the top of the base to assist in aligning the tip of the centering rod with the center of the prism. The present invention can reduce the error of the wire measurement, improve the accuracy of the excavation construction, and reduce the construction cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a schematic diagram of the overall structure of the present invention; Figure 2 It is another overall structural schematic diagram of the present invention; Figure 3 This is a schematic diagram of the structure of the present invention without the prism base and prism; In the attached figure: 1-tray base; 2-screw; 3-screw handle; 4-connecting centering rod; 5-prism base; 6-prism; 7-base; 8-circular level bubble; 9-level tube bubble. DETAILED DESCRIPTION

[0015] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0016] In the description of the present invention, it should be understood that the terms "upper", "lower", "front", "back", "left", "right", "top", "bottom", "inside", "outside", etc., indicating directions or positional relationships, are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore should not be understood as limiting the present invention. Example 1

[0017] Reference Figure 1 and Figure 2 , an adjustable forced centering bracket for circular tunnel wire measurement, comprising: a tray base 1, a screw 2, a connecting centering rod 4, a prism base 5, a prism 6, and a base 7; the tray base 1 is a triangular frame structure with a through groove inside, and a threaded hole is provided on each triangle of the tray base 1, two of which are respectively sleeved with a screw 2, and the remaining threaded hole is sleeved with a connecting centering rod 4, and the screw 2 and the connecting centering rod 4 are both perpendicular to the horizontal plane; the base 7 is provided above the connecting threaded hole of the tray base 1 connecting the centering rod 4, and the center of the base 7 is provided with the same threaded hole as the tray base 1, the prism base 5 is placed above the base 7, and the prism 6 is mounted on the prism base 5.

[0018] Preferably, in this embodiment, a screw handle 3 is provided on the top of the screw 2, and the screw handle 3 is a hexagonal prism.

[0019] Preferably, in this embodiment, the bottom of the screw 2 is conical.

[0020] Preferably, in this embodiment, the bottom of the connecting centering rod 4 is conical, and the top of the connecting centering rod 4 is a section of thread. In this embodiment, the length of the thread section is 20 mm.

[0021] Specifically, in this embodiment, the pallet base 1 is made of a 10mm thick steel plate. The pallet base 1 is an equilateral triangle of 313mm. The three outer corners of the pallet base 1 are processed into inner chamfers with a chamfer radius of 25mm. The outer edge of the pallet base 1 is cut 40mm inward to the center to remove the center steel plate, forming a hollow inner chamfered triangle. The two corners of the triangle are cut into chamfers with a chamfer radius of 25mm, and the other chamfer is 60mm. All the cut edges are polished smooth, and then the outer edges are cut into rounded corners. The center of the circle is 33mm inward from the rounded corner line of the outer edge of the triangle, and a screw hole with a diameter of 20mm is opened at the center of the circle to form the screw hole of the screw rod 2. The screw rod 2 is made of a 314mm screw rod that matches the screw hole opened in the tray base 1. One end of the screw rod is polished into a conical tip to form the screw rod; the screw handle 3 is made of hard rubber with a diameter of 34mm and a height of 28mm. The screw handle 3 is provided with a convex and concave pattern; it is made of 20mm round steel with a length of 150mm and connected to the centering rod 4; Preferably, in this embodiment, a circular level bubble 8 and a level bubble 9 are provided on the prism base 5. It should be noted that the prism base 5 is an existing finished product. As an example, in this embodiment, a commercially available Topcon GPH1 prism base 5 can be directly used.

[0022] In this embodiment, when using an adjustable forced centering bracket for circular tunnel conductor measurement, the adjustable forced centering bracket for circular tunnel conductor measurement is set up on the measurement control point so that the connecting centering rod 4 is against the top center of the measurement control point, and then a screw is used to perform rough leveling to level the tray base 1, that is, the prism is roughly leveled. After rough leveling, the prism base 5 circular level bubble 8 and the level tube bubble 9 are used as a reference for fine leveling, and the measuring prism base 5 is stabilized. Then, the prism surface is facing the direction of the alignment measurement total station, and the total station can clearly see the front and rear prism surfaces to complete the corresponding measurement work. Example 2

[0023] Based on Example 1, please refer to Figure 3 Preferably, in this embodiment, a plurality of annular scale lines are provided on the top of the base 7. It should be noted that when the connection point of the centering rod 4 is on the measurement control point, it is necessary to ensure that the tip of the centering rod 4 and the center of the prism are at the same coordinate, and the error does not exceed about 0.5 mm. In order to improve the alignment accuracy of the tip of the centering rod 4 and the center of the prism, a plurality of annular scale lines are provided on the top of the base 7 for reference.

[0024] The above are merely preferred embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Replacement may be partial structure, device, or method step replacement, or it may be a complete technical solution. Equivalent replacements or modifications based on the technical solution and inventive concept of the present invention are all within the scope of protection of the present invention.

Claims

1. An adjustable forced centering bracket for circular tunnel conductor measurement, characterized in that: include: A tray base (1), a screw (2), a connecting centering rod (4), a prism base (5), a prism (6), and a base (7); the tray base (1) is a triangular frame structure with a through groove provided inside, a threaded hole is provided on each triangle of the tray base (1), two threaded holes are respectively sleeved with a screw (2), and the remaining threaded hole is sleeved with a connecting centering rod (4), and the screw (2) and the connecting centering rod (4) are both perpendicular to the horizontal plane; the base (7) is provided above the connecting threaded hole of the tray base (1) connecting the centering rod (4), and the center of the base (7) is provided with the same threaded hole as the tray base (1), the prism base (5) is placed above the base (7), and the prism (6) is mounted on the prism base (5).

2. The adjustable forced centering bracket for circular tunnel conductor measurement according to claim 1, characterized in that: A screw handle (3) is provided on the top of the screw (2), and the screw handle (3) is a hexagonal prism.

3. The adjustable forced centering bracket for circular tunnel conductor measurement according to claim 1 or 2, characterized in that: The bottom of the screw (2) is conical.

4. The adjustable forced centering bracket for circular tunnel conductor measurement according to claim 1, characterized in that: The bottom of the connecting centering rod (4) is conical, and the top of the connecting centering rod (4) is a section of thread.

5. The adjustable forced centering bracket for circular tunnel conductor measurement according to claim 1, characterized in that: A circular level bubble (8) and a level tube bubble (9) are provided on the prism base (5).

6. The adjustable forced centering bracket for circular tunnel conductor measurement according to claim 1, characterized in that: A plurality of annular scale lines are provided on the top of the base (7).

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