Measuring device for adjusting line shape of main cable reference strand

Abstract

The utility model relates to the technical field of main cable shape adjustment, in particular to a measuring device for main cable reference strand shape adjustment. The measuring device comprises a rotary mounting seat, a GNSS receiver and a counterweight piece, and the rotary mounting seat is used for being rotationally connected with a reference cable strand; the GNSS receiver is connected with the rotary mounting seat; and the counterweight piece is connected with the rotary mounting seat and is used for enabling the GNSS receiver to be always positioned above the rotary mounting seat in the vertical direction. The problems that in the prior art, a GNSS receiver is fixed to a reference cable strand through a double-prism base, cable strand torsion drives the GNSS receiver to incline, and a measurement result is distorted can be solved.

Description

Technical Field

[0001] This invention relates to the field of main cable alignment adjustment technology, and more specifically to a measuring device for adjusting the alignment of the reference strands of a main cable. Background Technology

[0002] The main cable is the primary load-bearing structural component of a suspension bridge, typically consisting of several strands. The erection of the main cable strands begins with the first strand (also known as the reference strand). The reference strand's characteristic points are adjusted using absolute elevation to determine its alignment. Other strands are adjusted using their elevation differences relative to the reference strand. Therefore, the alignment of the reference strand in a suspension bridge is crucial. Adjusting the reference strand alignment relies on high-quality measurement results. Based on the alignment measurement results, along with other measurements such as tower deflection and main cable temperature, the adjustment length is determined through iterative processes. The quality of the adjustment and the workload are directly related to the measurement method. The adjustment of the reference strand alignment and stability observation generally employs a total station measurement method. This method requires manual adjustment of the prism direction and is highly susceptible to weather conditions; work cannot be carried out in foggy or windy weather. The larger the span of the suspension bridge, the greater the measurement difficulty. Similar patents all innovate in total station surveying fixtures, including 360° miniature prisms, double prisms, triangular prisms, and quadrangular prisms. Essentially, these all fall under the category of manual total station surveying, without changing the labor intensity; increasing the number of prisms actually increases the workload. For ultra-long-span suspension bridges, in environments such as oceans, rivers, and canyons, the reference cable strands are constantly subjected to wind-induced vibrations, and total station surveying introduces prism alignment errors. In summary, traditional methods for adjusting the reference cable strand alignment using total station surveying are costly, have many limitations, and have always been a difficult problem in the construction of long-span suspension bridges.

[0003] GNSS-RTK measurement methods have advantages such as high measurement accuracy, good spatiotemporal independence of measurement results, no need for line of sight, and continuous monitoring, and can complement total station measurements.

[0004] However, the installation method of the GNSS receiver on the reference cable strand is a challenge. As is well known, the reference cable strand will twist under sunlight. If a biprism base is used to fix the GNSS receiver on the reference cable strand, the twisting of the strand will cause the GNSS receiver to tilt, resulting in distorted measurement results. Summary of the Invention

[0005] To address the shortcomings of existing technologies, the present invention aims to provide a measuring device for adjusting the alignment of the reference strand of the main cable. This device solves the problem in existing technologies where a double-prism base is used to fix the GNSS receiver to the reference strand, causing the GNSS receiver to tilt due to strand twisting, which leads to distorted measurement results.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0007] This application provides a measuring device for adjusting the alignment of the reference strands of a main cable, comprising:

[0008] A rotatable mounting base for rotatably connecting to the reference cable strand;

[0009] A GNSS receiver is connected to the rotary mount.

[0010] A counterweight, connected to the rotary mounting base, is used to ensure that the GNSS receiver is always positioned above the rotary mounting base in the vertical direction.

[0011] In some alternative embodiments, the rotary mounting base includes:

[0012] The mounting base has a circular mounting space inside;

[0013] A bearing, which is fitted onto the reference strand and disposed within the circular mounting space.

[0014] In some alternative embodiments, the mounting base includes:

[0015] The base has an upward-opening lower semi-circular groove inside;

[0016] The cover has an upper semi-circular groove with an opening facing downwards, which is used to cover the top of the base and is connected by bolts.

[0017] In some alternatives, the bearing is a semi-circular mating bearing.

[0018] In some alternative embodiments, the rotary mount also includes a filler disposed inside the bearing to abut against the bearing and the reference strand.

[0019] In some alternative configurations, the counterweight and the GNSS receiver are located on the same radial line as the bearing.

[0020] In some alternative solutions, the counterweight is a stabilizer bar, and the axis of the stabilizer bar is located on the radial line.

[0021] In some alternative embodiments, the measuring device further includes a prism assembly connected to the counterweight.

[0022] In some alternative embodiments, the prism assembly includes a first prism and a second prism, the mirror surfaces of which are opposite in orientation.

[0023] In some alternative configurations, the first prism and the second prism are arranged sequentially along the vertical direction.

[0024] Compared with existing technologies, the advantages of this invention are as follows: by designing the rotary mounting base and the reference cable strand as a rotatable connection, the counterweight ensures that the GNSS receiver is always positioned above the vertical direction of the rotary mounting base. Even when the reference cable strand twists under sunlight, the GNSS receiver in this design will always remain above the vertical direction of the rotary mounting base. The GNSS receiver is always positioned above the reference cable strand relative to it, rather than twisting along with it. Because its position relative to the reference cable strand is fixed, the accuracy of the measurement results is improved. Attached Figure Description

[0025] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0026] Figure 1 This is the structure of the measuring device for adjusting the main cable reference strand alignment in this embodiment of the invention;

[0027] Figure 2 This is a schematic diagram of a GNSS receiver in an embodiment of the present invention;

[0028] Figure 3 This is a schematic diagram of the rotating mounting base in an embodiment of the present invention;

[0029] Figure 4 This is a schematic diagram of the prism assembly in an embodiment of the present invention.

[0030] In the diagram: 1. Rotary mounting base; 11. Mounting base; 111. Base; 112. Cover;

[0031] 12. Bearing; 13. Filler; 2. Reference cable strand; 3. GNSS receiver; 4. Counterweight; 5. Prism assembly; 51. First prism; 52. Second prism. Detailed Implementation

[0032] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0033] The embodiments of the present invention will be further described in detail below with reference to the accompanying drawings.

[0034] like Figures 1 to 4 As shown, this utility model provides a measuring device for adjusting the alignment of a reference strand of a main cable, comprising: a rotating mounting base 1, a GNSS receiver 3, and a counterweight 4. The rotating mounting base 1 is rotatably connected to the reference strand 2; the GNSS receiver 3 is connected to the rotating mounting base 1; and the counterweight 4 is connected to the rotating mounting base 1 to ensure that the GNSS receiver 3 is always positioned above the vertical direction of the rotating mounting base 1.

[0035] In this scheme, the rotating mounting base 1 is mounted on the reference cable strand 2 and rotatably connected to it. The counterweight 4 is connected to the rotating mounting base 1. Because the rotating mounting base 1 is rotatably connected to the reference cable strand 2, the counterweight 4 ensures that the GNSS receiver 3 is always vertically above the rotating mounting base 1. When the reference cable strand 2 twists under sunlight, with the measuring device of this scheme, the GNSS receiver 3 will always be vertically above the rotating mounting base 1. The GNSS receiver 3 is always positioned above the reference cable strand 2 relative to it, rather than twisting with it. This fixed position relative to the reference cable strand 2 improves the accuracy of the measurement results.

[0036] In this example, the counterweight 4 is located below the rotary mount 1, serving to provide counterweight to the rotary mount 1. The rotary mount 1 is rotatable relative to the reference cable strand 2 in the circumferential direction, and can rotate relative to the reference cable strand 2 to cooperate with the counterweight 4 to maintain the positional relationship between the GNSS receiver 3 and the reference cable strand 2.

[0037] In this embodiment, the counterweight 4 and the rotating mounting base 1 are designed as separate units, i.e., the counterweight 4 and the rotating mounting base 1 are two separate components. In other embodiments, the rotating mounting base 1 and the counterweight 4 can also be designed as a single unit, i.e., the rotating mounting base 1 and the counterweight 4 can be designed as one component, and different densities of materials can be used at different positions of the rotating mounting base 1. For example, a denser material can be used at the position away from the GNSS receiver 3. In this way, when the rotating mounting base 1 is installed on the reference cable strand 2, the GNSS receiver 3 can be kept vertically above the rotating mounting base 1, i.e., the position of the GNSS receiver 3 relative to the reference cable strand 2 can be maintained.

[0038] like Figure 3 As shown, in some optional embodiments, the rotary mounting base 1 includes a mounting base 11 and a bearing 12. The mounting base 11 has a circular mounting space; the bearing 12 is used to be sleeved on the reference cable strand 2 and is disposed within the circular mounting space.

[0039] In this embodiment, in order to achieve the stability of the rotating mounting base 1 relative to the reference cable strand 2, the rotating mounting base 1 is designed to be sleeved on the reference cable strand 2 by bearing 12 and installed in the circular mounting space of the mounting base 11. The GNSS receiver 3 and the counterweight 4 are respectively on the mounting base 11 and located on both sides of the circular mounting space in the radial direction. In this way, when the bearing 12 is sleeved on the reference cable strand 2 and placed in the circular mounting space, the counterweight 4 will always be located below the rotating mounting base 1, and the GNSS receiver 3 will be located above the rotating mounting base 1.

[0040] In some optional embodiments, the mounting base 11 includes a base 111 and a cover 112. The base 111 has a lower semicircular groove with an upward opening; the cover 112 has an upper semicircular groove with a downward opening, for covering the top of the base 111 and connected by bolts.

[0041] In this embodiment, to facilitate the installation of the bearing 12, the mounting base 11 is designed to include a base 111 and a cover 112, with the base 111 and the cover 112 respectively having an upward-opening lower semicircular groove and a downward-opening upper semicircular groove. In use, after the bearing 12 is fitted onto the reference cable 2, the bearing 12 is placed in the lower semicircular groove of the base 111, and the cover 112 is closed, securing the bearing 12 within the circular mounting space formed by the lower and upper semicircular grooves.

[0042] In some optional embodiments, bearing 12 is a semi-circular mating bearing. Specifically, bearing 12 uses two semi-circular needle roller bearings. After selecting the installation point of the measuring device, the two semi-circular needle roller bearings are spliced ​​together, and the reference cable 2 is placed inside the two semi-circular needle roller bearings and fixed relative to the inner ring of the two semi-circular needle roller bearings. Then, bearing 12 is placed in the lower semi-circular groove of base 111, and the cover 112 is covered to hold bearing 12 in the circular installation space formed by the lower and upper semi-circular grooves. This design facilitates the installation of the entire measuring device.

[0043] In some alternative embodiments, the rotary mounting base 1 further includes a filler 13 disposed inside the bearing 12 for abutting against the bearing 12 and the reference cable 2.

[0044] like Figure 2As shown, in this example, to ensure the relative fixation of the inner side of the bearing 12 with the reference cable strand 2, and to prevent the bearing 12 from damaging the reference cable strand 2 when it is fitted onto the outer side of the reference cable strand 2, a filler material 13, such as tape, is first wrapped around the mounting point of the bearing 12 on the reference cable strand 2 before installing the bearing 12 onto the reference cable strand 2. After wrapping the filler material 13 to a certain thickness on the reference cable strand 2, the bearing 12 is placed on the outer side of the filler material 13. This prevents the bearing 12 from directly contacting the reference cable strand 2, reducing the possibility of the bearing 12 squeezing the reference cable strand 2 and causing damage to it.

[0045] In some alternative embodiments, the counterweight 4 and the GNSS receiver 3 are located on the same radial line as the bearing 12.

[0046] In this embodiment, the counterweight 4 and the GNSS receiver 3 are located on the same radial line as the bearing 12, which ensures that the GNSS receiver 3 is always positioned vertically above the bearing, thus enabling better reception of positioning signals.

[0047] In some alternative embodiments, the counterweight 4 is a stabilizer bar, and the axis of the stabilizer bar is located on a radial line.

[0048] In this embodiment, the stabilizer bar is installed at the bottom of the base 111 and acts as a counterweight to keep the center of gravity of the entire measuring device below the reference cable strand, thereby keeping the base 111 always in the vertical plane and the GNSS receiver 3 always in the vertical direction above.

[0049] In some alternative embodiments, the measuring device also includes a prism assembly 5, which is connected to the counterweight 4.

[0050] In this embodiment, the prism assembly 5 is positioned below the counterweight 4, i.e., below the stabilizing rod. The prism assembly 5 provides some gravity, further improving the stability of the entire detection device, i.e., keeping the prism assembly 5 below the rotary mount 1 and the GNSS receiver 3 above the rotary mount 1. The prism assembly 5 is used in conjunction with a total station set up on the shore to measure the position of the detection device, comparing it with the data detected by the GNSS receiver 3 to confirm and align the data detected by the GNSS receiver 3.

[0051] like Figure 4 As shown, in some optional embodiments, the prism assembly 5 includes a first prism 51 and a second prism 52, the mirror surfaces of the first prism 51 and the second prism 52 having opposite orientations.

[0052] In this embodiment, the mirror surfaces of the first prism 51 and the second prism 52 are opposite, facing the observation stations on both sides of the bridge respectively, in order to realize the verification between measurement results.

[0053] In some alternative embodiments, the first prism 51 and the second prism 52 are arranged sequentially in the vertical direction.

[0054] In this embodiment, the first prism 51 and the second prism 52 are arranged sequentially along the vertical direction, which can improve the stability of the entire measuring device and keep the first prism 51 and the second prism 52 in the vertical direction. In addition, it also facilitates the calculation of the position of the first prism 51 and the second prism 52 relative to the reference cable strand 2.

[0055] On the other hand, a method for adjusting the main cable reference strand alignment is also provided, which is implemented using the aforementioned measuring device for adjusting the main cable reference strand alignment.

[0056] First, based on the bridge construction control network, a GNSS-RTK monitoring reference station was established to obtain coordinate system transformation parameters, and the GNSS measurement results were transformed into the bridge coordinate system.

[0057] Install this measuring device at the mid-span of the reference cable strand. Start GNSS-RTK automated monitoring; conduct total station measurements to confirm the consistency between the total station and GNSS-RTK measurement results.

[0058] Cable adjustment begins at night when temperatures are stable. The baseline cable strand alignment is adjusted using GNSS-RTK monitoring results. The GNSS-RTK monitoring results are time series (x, y, z; t). A monitoring data series over a period of time (e.g., 5 minutes) is taken, first processed using low-pass filtering; then the average coordinates are taken to obtain the average position of the mid-span measuring point. , , According to the x-axis Offset correction elevation coordinates Based on mileage coordinates Offset correction elevation coordinates .

[0059] Based on the measured results of other structural parameters during the GNSS-RTK monitoring period, such as main tower offset, tower top elevation, and reference cable strand temperature, the theoretical position (x0, y0, z0) of the reference cable strand mid-span measuring point (measuring device) is obtained according to the calculation formula in the monitoring instructions. Based on the elevation target difference ( (-z0) Obtain the baseline cable length adjustment amount, notify the cable adjustment personnel, and the cable adjustment can begin.

[0060] After adjustment, repeat the above measurement and data analysis process to achieve an iterative cycle of adjustment until the elevation target difference is reached. -z0) meets the requirements.

[0061] After the baseline cable strand alignment is adjusted, the cable adjustment results need to be stabilized for three consecutive days. The stabilization measurement method is the same as the cable adjustment measurement method, except that the cable length adjustment is no longer calculated. Since GNSS-RTK is used to automate the measurement of the mid-span coordinates, it is no longer necessary to manually walk along the catwalk to the mid-span measurement point, thus reducing the workload.

[0062] The advantages of this invention are: by using a bearing base structure to isolate the torsional deformation of the reference cable strand, GNSS-RTK can be used to monitor the coordinates of the reference cable strand, giving full play to the measurement advantages of GNSS-RTK, transforming the traditional problem of manual measurement of the reference cable strand of long-span suspension bridges into automated monitoring by GNSS-RTK, reducing the labor intensity of surveyors, improving the quality of measurement results, and achieving efficient adjustment of the alignment of the reference cable strand of the main cable of long-span suspension bridges.

[0063] In the description of this application, it should be noted that the terms "upper," "lower," etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application. Unless otherwise expressly specified and limited, the terms "installed," "connected," and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication between two elements. For those skilled in the art, the specific meaning of the above terms in this application can be understood according to the specific circumstances.

[0064] It should be noted that in this application, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0065] The above description is merely a specific embodiment of this application, enabling those skilled in the art to understand or implement this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features claimed herein.

Claims

1. A measuring device for adjusting the alignment of the reference strands of a main cable, characterized in that, include: Rotary mounting base (1) for rotatably connecting with reference cable strand (2); A GNSS receiver (3) is connected to the rotary mount (1); A counterweight (4), which is connected to the rotary mounting base (1), is used to ensure that the GNSS receiver (3) is always positioned above the rotary mounting base (1) in the vertical direction.

2. The measuring device for adjusting the alignment of the reference strands of the main cable as described in claim 1, characterized in that, The rotary mounting base (1) includes: Mounting base (11), which has a circular mounting space inside; The bearing (12) is used to be fitted onto the reference strand (2) and is located within the circular mounting space.

3. The measuring device for adjusting the alignment of the reference strands of the main cable as described in claim 2, characterized in that, The mounting base (11) includes: The base (111) has an upward-opening lower semi-circular groove inside; The cover (112) has an upper semi-circular groove with an opening facing downward, which is used to cover the top of the base (111) and is connected by bolts.

4. The measuring device for adjusting the alignment of the reference strands of the main cable as described in claim 2, characterized in that, The bearing (12) is a semi-circular mating bearing.

5. The measuring device for adjusting the alignment of the reference strands of the main cable as described in claim 2, characterized in that, The rotary mounting base (1) also includes a filler (13) disposed inside the bearing (12) for abutting against the bearing (12) and the reference cable (2).

6. The measuring device for adjusting the alignment of the reference strands of the main cable as described in claim 2, characterized in that, The counterweight (4) and the GNSS receiver (3) are located on the same radial line as the bearing (12).

7. The measuring device for adjusting the alignment of the reference strands of the main cable as described in claim 6, characterized in that, The counterweight (4) is a stabilizer bar, and the axis of the stabilizer bar is located on the radial line.

8. The measuring device for adjusting the alignment of the reference strand of the main cable as described in any one of claims 1-7, characterized in that, The measuring device also includes a prism assembly (5), which is connected to the counterweight (4).

9. The measuring device for adjusting the alignment of the reference strands of the main cable as described in claim 8, characterized in that, The prism assembly (5) includes a first prism (51) and a second prism (52), the mirror surfaces of the first prism (51) and the second prism (52) having opposite orientations.

10. The measuring device for adjusting the alignment of the reference strands of the main cable as described in claim 9, characterized in that, The first prism (51) and the second prism (52) are arranged sequentially in the vertical direction.

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