Shield tunnel segment slab staggering measuring scale and using method thereof

Abstract

The invention provides a shield tunnel segment dislocation measuring scale and a use method thereof, and relates to the technical field of constructional engineering, the shield tunnel segment dislocation measuring scale comprises a scale body, a storage cavity is formed in the scale body, a rotary measuring scale is movably connected in the storage cavity, a rotary guide block is rotatably connected in the storage cavity, and the rotary guide block is movably connected in the storage cavity. The staggered slab measuring ruler for the shield tunnel segment comprises a ruler body, a rotary guide block is arranged in the ruler body, a measuring ruler guide opening is formed in the center of the rotary measuring ruler, the rotary guide block is in sliding connection with the measuring ruler guide opening, and a control panel is fixedly connected to the upper surface of the ruler body. The measuring ruler in a contracted state is convenient to carry and more flexible in scene measurement, and solves the problem that a reference straight rod is horizontally placed on the surface of a lower segment, then a steel ruler is used for measuring the vertical distance from the edge of an adjacent higher segment to the lower edge of the straight rod, and the vertical distance serves as a slab staggering value. And inaccurate reading is caused.

Description

Technical Field

[0001] This invention relates to the field of building engineering technology, and in particular to a measuring ruler for misalignment of tunnel segments and its method of use. Background Technology

[0002] With increasing pressure on urban land use and transportation, the shield tunneling method has become the mainstream method for subway and urban rail tunnel construction due to its advantages such as speed, safety, environmental protection and controllable quality. This method uses precast segments to assemble into rings to support the tunnel structure. However, due to factors such as geological conditions, propulsion parameters and operator skill, misalignment often occurs between the segments.

[0003] Currently, misalignment measurement mainly relies on simple measuring tools. During operation, a reference straight rod is placed horizontally on the surface of the lower segment, and then a steel ruler is used to measure the vertical distance from the edge of the adjacent higher segment to the lower edge of the straight rod. This distance is used as the misalignment value. This measurement method may cause visual deviation due to looking up, resulting in inaccurate readings and affecting the accuracy of recording and evaluation. If construction is carried out based on the evaluation accuracy with deviation, it will lead to hidden dangers in the sealing and safety of tunnel segment splicing. Summary of the Invention

[0004] This invention provides a measuring ruler for misalignment measurement of tunnel segments and its usage method, which solves the problem that current misalignment measurement mainly relies on simple measuring tools. During operation, a reference straight rod is placed horizontally on the surface of the lower segment, and then a steel ruler is used to measure the vertical distance from the edge of the adjacent higher segment to the lower edge of the straight rod, which is used as the misalignment value. This measurement method may cause visual deviation due to upward observation, resulting in inaccurate readings and affecting the accuracy of recording and evaluation. If construction is carried out based on the evaluation accuracy with deviation, it will lead to hidden dangers in the sealing and safety of tunnel segment splicing.

[0005] This invention provides a measuring ruler for misalignment of tunnel segments and its usage method, specifically comprising: a ruler body, an internal storage cavity, a movably connected rotating measuring ruler inside the storage cavity, a rotating guide block rotatably connected inside the storage cavity, a measuring ruler guide opening at the center of the rotating measuring ruler, a slidably connected rotating guide block and measuring ruler guide opening, a control panel fixedly connected to the upper surface of the ruler body, an infrared ranging probe located on the right edge of the rear surface of the ruler body, the infrared ranging probe being connected to the control panel via an electrical connection wire, a battery mounting port located at the right end of the ruler body, and graduation marks located on the edge of the upper surface of the rotating measuring ruler.

[0006] Furthermore, a directional push seat is fixedly inserted into the center of the left end face of the ruler body, the right end of the directional push seat is located inside the storage cavity, a push seat guide opening is opened on the right end face of the directional push seat, a push seat guide rod is slidably connected inside the push seat guide opening, and a directional push plate is fixedly connected to the right end of the push seat guide rod.

[0007] Furthermore, the push base guide rod is sleeved with a directional push spring, and the two ends of the directional push spring are respectively fixedly connected to the directional push plate and the directional push base. The push base guide opening and the push base guide rod both have a square structure in cross section.

[0008] Furthermore, a baffle is fixedly connected to the rear edge of the storage cavity, and a strap is connected to the outside of the ruler body by a buckle, with the strap vertically covering the front opening of the storage cavity.

[0009] Furthermore, the end of the rotary measuring ruler has a semi-circular head structure, and a measuring ruler guide is longitudinally opened through the center of the rotary measuring ruler. A guide strip is protruding from the inner wall of the measuring ruler guide. A side guide groove is opened on the outer surface of the rotary guide block. The rotary guide block is slidably connected to the measuring ruler guide, and the side guide groove is slidably connected to the guide strip.

[0010] Furthermore, the side of the rotary measuring ruler is provided with a side directional groove, the semi-circular head surface of the rotary measuring ruler is provided with an end directional groove, the side directional groove is perpendicular to the end directional groove, and the lower edge of the guide of the measuring ruler is provided with an anti-slip cavity with a beveled structure.

[0011] Furthermore, a limiting plate is slidably connected to the lower surface of the ruler body, and the upper front edge of the limiting plate is provided with a wedge edge with a beveled structure.

[0012] Furthermore, the bottom of the ruler body is provided with a lower opening, which connects to the storage cavity, and a friction locking block is slidably connected inside the lower opening.

[0013] Furthermore, the bottom of the friction lock block is provided with a lock block push surface with a sloping structure, and lock block connecting plates are fixedly connected to both sides of the friction lock block. A lock block top spring is fixedly connected to the upper surface of the lock block connecting plate, and the upper end of the lock block top spring is fixedly connected to the lower surface of the ruler body.

[0014] Furthermore, the method of use includes the following steps: In a low-light environment, the rear surface of the ruler is attached to the upper tunnel segment, so that the infrared ranging probe is located above the lower tunnel segment. The distance between the ruler and the lower segment can be measured by the infrared ranging probe, and the distance value is displayed on the control panel, thereby measuring the misalignment value. In a well-lit environment, loosen the straps and rotate the rotary measuring ruler forward. When the rotary measuring ruler is perpendicular to the front surface of the ruler body, the directional push plate slides into the side directional groove to limit the angle of the rotary measuring ruler and maintain its perpendicularity. With the end of the rotary measuring ruler perpendicular to the lower pipe wall surface and the ruler body pushed downward, the front surface of the ruler body is made to fit against the upper pipe wall surface. During this process, the rotary measuring ruler slides and retracts into the storage cavity, and the rotary guide block slides with the guide of the measuring ruler. The reset spring is stretched and stores force. When the front surface of the ruler is in contact with the upper pipe wall surface, push the limiting plate so that the wedge edge of the plate is in contact with and squeezed against the locking block push surface, push the friction locking block into the receiving cavity and fit tightly with the anti-slip cavity, fix the rotary measuring ruler by friction, retrieve the measuring ruler, read and record the value according to the outer scale line of the rotary measuring ruler. Thus, the shield tunnel segment misalignment measurement work is completed.

[0015] This invention provides a measuring ruler for measuring misalignment of tunnel segments and its method of use, which has the following beneficial effects: The shield tunnel segment misalignment measuring ruler of this invention has multiple forms. The rotary measuring ruler can be rotated and retracted inside the ruler body. The retracted measuring ruler is easy to carry and more flexible for measurement scenarios. It also has a dual-mode angle limiting function, so that the extended rotary measuring ruler is perpendicular to the ruler body. In conjunction with the telescopic rotary measuring ruler, during the measurement process, the ruler body is in contact with the surface of the upper tunnel segment, and the rotary measuring ruler is perpendicular to the surface of the lower tunnel segment. In this state, the rotary measuring ruler retracts into the storage cavity. By observing the reading of the scale on the rotary measuring ruler at the contact point with the ruler body, the misalignment dimension of the tunnel segment can be measured, avoiding the reading deviation caused by the reading angle in traditional measurement methods.

[0016] In addition, the present invention is equipped with an infrared ranging probe, which can also measure the misalignment of tunnel segments. During operation, the ruler is placed in contact with the upper tunnel segment, so that the infrared ranging probe is above the lower tunnel segment. The distance between the ruler and the lower segment can be measured by the infrared ranging probe, and the distance value can be displayed on the control panel. The measuring device has multiple measurement modes and can be applied to various usage scenarios, thus improving the applicability of the measuring ruler.

[0017] Furthermore, this invention features a quick-locking structure for the rotary measuring ruler. Through the cooperation of the limiting plate and the friction locking block, pushing the limiting plate can push the friction locking block into the anti-slip cavity. The rotary measuring ruler is locked by friction, allowing it to remain in the measurement position for easy reading. The structure is simple, and it can accurately measure the misalignment of pipe segments. The measurement results are accurate and it has a wide range of applications. Attached Figure Description

[0018] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings of the embodiments will be briefly described below.

[0019] The accompanying drawings described below are only related to some embodiments of the invention and are not intended to limit the invention.

[0020] In the attached diagram: Figure 1 A schematic diagram of the overall structure of this application is shown; Figure 2A schematic diagram of the structure of the rotary measuring ruler of this application in its retracted state is shown; Figure 3 A structural schematic diagram following this application is shown; Figure 4 A structural schematic diagram of the bottom of this application is shown; Figure 5 A schematic diagram of the structure of the rotary measuring ruler of this application when unfolded is shown; Figure 6 This paper shows a schematic diagram of the internal structure of the directional push base of this application; Figure 7 A schematic diagram of the rotating guide block of this application is shown; Figure 8 This application shows Figure 7 A schematic diagram of the bottom structure; Figure 9 This diagram shows the structure of the limiting plate, friction lock block and ruler body when they are separated. Figure 10 This diagram shows the structure of the limiting insert plate of this application when it is pulled back. Figure 11 This application shows Figure 9 A magnified structural diagram of point A in the middle.

[0021] Figure label: 1. Ruler body; 101. Storage cavity; 102. Baffle; 103. Strap; 104. Lower opening; 2. Orientation push base; 201. Push base guide opening; 202. Push base guide rod; 203. Orientation push plate; 204. Orientation push spring; 3. Rotating guide block; 301. Side guide groove; 302. Tension spring storage opening; 303. Reset tension spring; 4. Rotary measuring ruler; 401. Measuring ruler guide opening; 402. Guide opening protrusion; 403. Side directional flat groove; 404. End directional flat groove; 405. Anti-slip insertion cavity; 5. Limiting insert plate; 501. Insert plate wedge edge; 6. Friction locking block; 601. Locking block push surface; 602. Locking block connecting plate; 603. Locking block top spring; 7. Control panel; 8. Infrared ranging probe; 9. Battery mounting port. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the described embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0023] Example 1: Please refer to Figures 1 to 11 : This invention proposes a measuring ruler for measuring misalignment of tunnel segments and its usage method, comprising: a ruler body 1, an internal storage cavity 101, a movably connected rotary measuring ruler 4 inside the storage cavity 101, a rotating guide block 3 rotatably connected inside the storage cavity 101, a measuring ruler guide opening 401 at the center of the rotary measuring ruler 4, the rotating guide block 3 slidably connected to the measuring ruler guide opening 401, a control panel 7 fixedly connected to the upper surface of the ruler body 1, an infrared ranging probe 8 located on the right edge of the rear surface of the ruler body 1, the infrared ranging probe 8 being connected to the control panel 7 via an electrical connection wire, a battery mounting port 9 located at the right end of the ruler body 1, and a battery mounting port 9 located on the upper edge of the rotary measuring ruler 4. It has graduations; when used in low-light environments, the infrared ranging probe 8 can be used to measure the misalignment of tunnel segments. When using it, the ruler body 1 is placed against the upper tunnel segment, so that the infrared ranging probe 8 is above the lower tunnel segment. The distance between the ruler body 1 and the lower segment can be measured through the infrared ranging probe 8, and the distance value can be displayed through the control panel 7. The display through the control panel 7 eliminates the need for manual reading from the ruler, making the reading more direct and eliminating concerns about unclear readings in low-light environments. This measuring ruler has multiple forms. The rotary measuring ruler 4 can be rotated and retracted inside the ruler body 1. The measuring ruler in the retracted state is easy to carry and more flexible for measurement scenarios.

[0024] In this embodiment, a directional push base 2 is fixedly inserted into the center of the left end face of the ruler body 1. The right end of the directional push base 2 is located inside the storage cavity 101. A push base guide opening 201 is provided on the right end face of the directional push base 2. A push base guide rod 202 is slidably connected inside the push base guide opening 201. A directional push plate 203 is fixedly connected to the right end of the push base guide rod 202. A directional push spring 204 is sleeved on the push base guide rod 202. The two ends of the directional push spring 204 are respectively fixedly connected to the directional push plate 203 and the directional push base 2. The cross-sections of the push base guide opening 201 and the push base guide rod 202 are both square. Under normal conditions, when the rotary measuring ruler 4 is retracted into the storage cavity 101... Inside the 1, the directional push spring 204 pushes the directional push plate 203 toward the rotary measuring ruler 4, so that the directional push plate 203 and the end directional flat groove 404 fit tightly together. Under the action of the two planes fitting together, the rotary measuring ruler 4 is not easy to wobble, and the rotary measuring ruler 4 is kept stored inside the storage cavity 101. A baffle 102 is fixedly connected to the rear edge of the storage cavity 101. A strap 103 is connected to the outside of the ruler body 1 by a buckle. The strap 103 vertically covers the front opening of the storage cavity 101. The baffle 102 and the strap 103 further limit the rotary measuring ruler 4, so that the rotary measuring ruler 4 cannot be rotated and unfolded.

[0025] In this embodiment, the end of the rotary measuring ruler 4 has a semi-circular head structure. A measuring ruler guide opening 401 is longitudinally provided through the center of the rotary measuring ruler 4. A guide ridge 402 protrudes from the inner wall of the measuring ruler guide opening 401. A side guide groove 301 is provided on the outer surface of the rotary guide block 3. The rotary guide block 3 is slidably connected to the measuring ruler guide opening 401, and the side guide groove 301 is slidably connected to the guide ridge 402. A side directional groove 403 is provided on the side of the rotary measuring ruler 4, and an end directional groove 404 is provided on the semi-circular head surface of the rotary measuring ruler 4. The side directional groove 403 and the end directional groove... 404 is vertical; when the rotary measuring ruler 4 is unfolded, the rotary measuring ruler 4 is manually rotated outward. As the rotary measuring ruler 4 rotates, the end directional groove 404 separates from the directional push plate 203, and the directional push plate 203 is pushed to the left, compressing the directional push spring 204. When the rotary measuring ruler 4 is perpendicular to the front surface of the ruler body 1, the directional push plate 203 slides into the side directional groove 403 and is parallel to the groove surface. At this time, the directional push plate 203 and the side directional groove 403 are in contact, which limits the angle of the rotary measuring ruler 4 and maintains the verticality of the rotary measuring ruler 4.

[0026] In Example 2, based on Example 1, a beveled anti-slip cavity 405 is provided on the lower edge of the measuring ruler guide 401. A limiting plate 5 is slidably connected to the lower surface of the ruler body 1. A beveled wedge edge 501 is provided on the upper front edge of the limiting plate 5. A lower through-hole 104 is provided at the bottom of the ruler body 1, connecting to the storage cavity 101. A friction locking block 6 is slidably connected inside the lower through-hole 104. A beveled locking block push surface 601 is provided at the bottom of the friction locking block 6. Locking block connecting plates 602 are fixedly connected to both sides of the friction locking block 6. A locking block top spring 603 is fixedly connected to the upper surface of the locking block connecting plate 602. The upper end of the locking block top spring 603 is fixedly connected to the lower surface of the ruler body 1. Under normal conditions, the limiting plate 5 and the friction locking block 6 do not contact each other. Under the action of the locking block top spring 603, the friction locking block 6 separates from the storage cavity 101. In this state, the rotary measuring ruler 4 can slide inside the storage cavity 101 and outside the rotating guide block 3 under the action of external force to move its position and achieve measurement. During the measurement process, the limiting plate 5 can be pushed to make the wedge edge 501 of the plate rub against the locking block push surface 601 and push the friction locking block 6 into the storage cavity 101, so that the end of the friction locking block 6 is tightly inserted into the anti-slip cavity 405. The rotary measuring ruler 4 is locked by friction, so as to prevent the rotary measuring ruler 4 from moving and affecting the reading. After the reading is completed, the limiting plate 5 is pushed back to reset the limiting plate 5 and the friction locking block 6, thereby releasing the lock on the rotary measuring ruler 4, so that the rotary measuring ruler 4 can be reset and folded for storage.

[0027] The working principle of this embodiment is as follows: First, when using a measuring ruler to measure the misalignment of shield tunnel segments, in a low-light environment, the rear surface of the ruler body 1 is placed against the upper tunnel segment, so that the infrared ranging probe 8 is positioned above the lower tunnel segment. The distance between the ruler body 1 and the lower segment can be measured through the infrared ranging probe 8, and the distance value is displayed on the control panel 7, thereby measuring the misalignment value. In a well-lit environment, the strap 103 is loosened, and the rotary measuring ruler 4 is rotated forward. As the rotary measuring ruler 4 rotates, the end directional groove 404 separates from the directional push plate 203, and the directional push plate 203 is pushed to the left, compressing the directional push spring 204. When the rotary measuring ruler 4 is perpendicular to the front surface of the ruler body 1, the directional push plate 203 slides into the side directional groove 403 and is parallel to the groove surface. At this time, the contact between the directional push plate 203 and the side directional groove 403 limits the angle of the rotary measuring ruler 4, maintaining the verticality of the rotary measuring ruler 4. Then, the end of the rotary measuring ruler 4 is perpendicular to the lower pipe wall surface, and the ruler body 1 is pushed downward, so that the front surface of the ruler body 1 is in contact with the upper pipe wall surface. During this process, the rotary measuring ruler 4 slides and retracts into the receiving cavity 101, and the rotary guide block 3 slides with the measuring ruler guide opening 401. The reset spring 303 is stretched and stores force. When the front surface of the ruler body 1 is in contact with the upper pipe wall surface, the limiting insert plate 5 is pushed, so that the insert plate wedge edge 501 is in contact with the locking block push surface 601 and squeezes, pushing and rubbing. The friction locking block 6 is inserted into the storage cavity 101 and fits tightly with the anti-slip insert cavity 405. The rotating measuring ruler 4 is fixed by friction, and the measuring ruler can be retrieved. The reading is taken according to the outer scale line of the rotating measuring ruler 4 and recorded. After the reading is completed, the limit insert 5 is pushed back to reset the limit insert 5 and the friction locking block 6, thereby releasing the lock on the rotating measuring ruler 4, resetting the rotating measuring ruler 4, and rotating the rotating measuring ruler 4 to retract it into the storage cavity 101.

[0028] The following points should be noted in this article: 1. The accompanying drawings of the embodiments disclosed herein only relate to the structures involved in the embodiments disclosed herein; other structures can be referred to in a general design.

[0029] 2. Where there is no conflict, the embodiments of this disclosure and the features in the embodiments can be combined with each other to obtain new embodiments.

[0030] The above are merely specific embodiments of this disclosure, but the scope of protection of this disclosure is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this disclosure should be included within the scope of protection of this disclosure. Therefore, the scope of protection of this disclosure should be determined by the scope of the claims.

Claims

1. A ruler for measuring misalignment of tunnel segments, characterized in that, include: The ruler body (1) has a storage cavity (101) inside. A rotary measuring ruler (4) is movably connected inside the storage cavity (101). A rotating guide block (3) is rotatably connected inside the storage cavity (101). A measuring ruler guide opening (401) is opened in the center of the rotary measuring ruler (4). The rotating guide block (3) is slidably connected to the measuring ruler guide opening (401). A control panel (7) is fixedly connected to the upper surface of the ruler body (1). An infrared ranging probe (8) is provided on the right edge of the rear surface of the ruler body (1). The infrared ranging probe (8) is connected to the control panel (7) through an electrical connection line. A battery mounting port (9) is opened at the right end of the ruler body (1). A scale mark is provided on the edge of the upper surface of the rotary measuring ruler (4).

2. A measuring ruler for measuring misalignment of tunnel segments according to claim 1, characterized in that, A directional pusher (2) is fixedly inserted into the center of the left end face of the ruler (1). The right end of the directional pusher (2) is located inside the storage cavity (101). A pusher guide (201) is opened on the right end face of the directional pusher (2). A pusher guide rod (202) is slidably connected inside the pusher guide (201). A directional pusher plate (203) is fixedly connected to the right end of the pusher guide rod (202).

3. A ruler for measuring misalignment of tunnel segments according to claim 2, characterized in that, The push base guide rod (202) is sleeved with a directional push spring (204). The two ends of the directional push spring (204) are respectively fixedly connected to the directional push plate (203) and the directional push base (2). The cross-sections of the push base guide port (201) and the push base guide rod (202) are both square.

4. A measuring ruler for measuring misalignment of tunnel segments according to claim 3, characterized in that, A baffle (102) is fixedly connected to the rear edge of the storage cavity (101), and a strap (103) is connected to the outside of the ruler body (1) by a buckle. The strap (103) vertically covers the front opening of the storage cavity (101).

5. A measuring ruler for measuring misalignment of tunnel segments according to claim 4, characterized in that, The end of the rotary measuring ruler (4) has a semi-circular head structure. The center of the rotary measuring ruler (4) has a longitudinally penetrating measuring ruler guide (401). The inner wall of the measuring ruler guide (401) has a guide strip (402). The outer surface of the rotary guide block (3) has a side guide groove (301). The rotary guide block (3) is slidably connected to the measuring ruler guide (401), and the side guide groove (301) is slidably connected to the guide strip (402).

6. A ruler for measuring misalignment of tunnel segments according to claim 5, characterized in that, The rotating measuring ruler (4) has a side directional groove (403) on its side and an end directional groove (404) on its semi-circular head surface. The side directional groove (403) is perpendicular to the end directional groove (404). The lower edge of the measuring ruler guide (401) has a sloped anti-slip cavity (405).

7. A ruler for measuring misalignment of tunnel segments according to claim 1, characterized in that, The lower surface of the ruler body (1) is slidably connected to a limiting plate (5), and the upper front edge of the limiting plate (5) is provided with a wedge edge (501) with a beveled structure.

8. A measuring ruler for measuring misalignment of tunnel segments according to claim 1, characterized in that, The bottom of the ruler body (1) is provided with a lower opening (104), which is connected to the storage cavity (101). A friction lock block (6) is slidably connected inside the lower opening (104).

9. A ruler for measuring misalignment of tunnel segments according to claim 8, characterized in that, The friction lock block (6) has a lock block push surface (601) with a sloping structure at its bottom. Lock block connecting plates (602) are fixedly connected to both sides of the friction lock block (6). Lock block top spring (603) is fixedly connected to the upper surface of the lock block connecting plate (602). The upper end of the lock block top spring (603) is fixedly connected to the lower surface of the ruler body (1).

10. A method for using a measuring ruler for measuring misalignment of tunnel segments according to any one of claims 1-9, characterized in that, Includes the following steps:

01. In a dark environment, the rear surface of the ruler (1) is attached to the upper tunnel segment, so that the infrared ranging probe (8) is located above the lower tunnel segment. The distance between the ruler (1) and the lower segment can be measured by the infrared ranging probe (8), and the distance value can be displayed by the control panel (7), thereby measuring the misalignment value.

02. In a well-lit environment, loosen the strap (103), rotate the rotary measuring ruler (4) forward, and when the rotary measuring ruler (4) is perpendicular to the front surface of the ruler body (1), slide the directional push plate (203) into the side directional flat groove (403) to limit the angle of the rotary measuring ruler (4) and maintain the verticality of the rotary measuring ruler (4); 03. Position the end of the rotary measuring ruler (4) perpendicular to the lower pipe wall surface and push the ruler body (1) downward so that the front surface of the ruler body (1) is in contact with the upper pipe wall surface. During this process, the rotary measuring ruler (4) slides and retracts into the receiving cavity (101), and the rotary guide block (3) slides with the measuring ruler guide (401), and the reset spring (303) stretches and stores force.

04. When the front surface of the ruler (1) is in contact with the upper pipe wall surface, push the limiting insert plate (5) so that the wedge edge (501) of the insert plate is in contact with and squeezed by the locking block push surface (601), push the friction locking block (6) into the receiving cavity (101) and fit tightly with the anti-slip insert cavity (405). Fix the rotating measuring ruler (4) by friction. Take back the measuring ruler, read the value according to the outer scale line of the rotating measuring ruler (4) and record it. Thus, the shield tunnel segment misalignment measurement work is completed.

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