A method for deploying an aerial control network for multi-tower bridge piers

Abstract

This invention relates to the field of bridge construction surveying technology, specifically to a method for establishing an aerial control network for multi-tower bridge piers. This method includes the following steps: using an aerial total station installed on the inner wall of the top of each tower pier to vertically project points downwards onto the pier platform; measuring the projection points of each aerial total station to obtain their observation coordinates; establishing an aerial geodetic polygon network with the centers of each aerial total station, and using the aerial total station to measure the observation side length between every two vertices of the aerial geodetic polygon network; determining the coordinates of the aerial total station based on the observation coordinates of each projection point and the observation side length between every two vertices of the aerial geodetic polygon network, thus establishing the aerial control network for the bridge piers. This method solves the problems of existing "bottom-up" methods being unsuitable for measuring control points of multi-tower bridge piers, resulting in complex procedures and extremely low measurement efficiency.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of bridge construction surveying, and particularly relates to a method for setting up an aerial control network of a multi-tower-leg bridge tower pier. BACKGROUND

[0002] With the development of kilometer-level cable-stayed bridges and suspension bridges, in order to meet the needs of structural bearing capacity, the tower pier type gradually appears as multi-tower-leg. For example, in a double-deck cable-stayed bridge, the main tower is a spatial diamond type, which is divided into three sections of upper tower column, middle tower column and lower tower column, and is a four-leg structure. A steel-concrete combined section is arranged after the four legs intersect. The middle tower is a four-tower-leg structure, which is complex and plays a role of connecting the upper and lower towers. The lower tower column or the pile cap is connected to the lower tower column, and the upper intersection is connected to the upper tower column.

[0003] In the construction process of the multi-tower-leg bridge tower pier, the spatial relationship between the tower legs in the air is complex. During the surveying, the verticality of the bridge tower pier center and each tower leg needs to be controlled, and the spatial geometric relationship between the multi-tower-legs also needs to be accurately controlled. In addition, the construction space is narrow, the construction facilities block the surveying line of sight, the surveying environment is poor, and the surveying control is difficult.

[0004] The bridge tower pier control point transfer surveying generally adopts a total station intersection surveying method and a total station zenith projection point surveying method. The intersection surveying of a tower leg control point generally needs more than three total stations to work for one to two hours. This is obviously not suitable for the multi-tower-leg control point surveying of a four-tower-leg structure, which has a large investment and low efficiency. In addition, the control points after the intersection surveying also need to be connected, which takes a longer time. In the total station zenith projection point surveying, the total station is first arranged on the pile cap (the lower part of the bridge tower pier), and then the prism is arranged on the top of the tower (the upper part of the tower leg of the bridge tower pier). That is, the "first bottom and then top" method. First, the total station is arranged on the pile cap of the bridge tower pier, and then the prism is arranged on the top of the tower leg of the bridge tower pier. The prism and the total station are strictly located on the same vertical line to meet the observation requirements of the zenith control point transfer surveying. Because the structure of the top of the multi-tower-leg bridge tower pier is complex and the large temporary construction facilities are dense, the zenith projection point line of sight is difficult to pass through. Therefore, in the process of observing the zenith control point by the total station at the bottom of the tower, the crosshairs of the total station telescope are used to search for and guide the zenith projection point prism to be in place in the high-altitude environment at the top of the tower, which is very difficult. This searching and positioning method of the high-altitude target needs to be repeatedly moved to be accurately positioned, which has low surveying efficiency, and the efficiency of the zenith projection point of the multi-tower-leg is even lower. In addition, in the case of serious construction interference and line of sight obstruction, the total station also needs to be repeatedly moved and re-arranged several times to make the zenith projection point prism and the total station strictly located on the same vertical line, so as to meet the observation requirements of the zenith control point transfer surveying. Obviously, this "first bottom and then top" method is not suitable for the control point surveying of the multi-tower-leg bridge tower pier, which has the defects of complicated process and extremely low surveying efficiency, and needs to be improved. SUMMARY

[0005] In view of the defects in the prior art, the purpose of the present application is to provide a multi-tower limb bridge tower pier aerial control network layout method, which can solve the problem that the prior art method of "first down and then up" is not suitable for multi-tower limb bridge tower pier control point measurement, and the process is complicated and the measurement efficiency is very low.

[0006] To achieve the above purpose, the technical scheme adopted by the present application is:

[0007] The present application provides a multi-tower limb bridge tower pier aerial control network layout method, comprising the following steps:

[0008] Using the aerial total station installed on the inner wall of the top end of each tower limb of the bridge tower pier to vertically project points downward onto the pile cap;

[0009] Measuring the projection points of each aerial total station to obtain the observation coordinates of each projection point;

[0010] Establishing an aerial geodetic polygon network with the center of each aerial total station, and measuring the observation edge length between each two vertices of the aerial geodetic polygon network using the aerial total station;

[0011] Determining the coordinates of the aerial total station according to the observation coordinates of each projection point and the observation edge length between each two vertices of the aerial geodetic polygon network, and establishing a bridge tower pier aerial control network.

[0012] In some optional schemes, the aerial total station installed on the inner wall of the top end of each tower limb of the bridge tower pier is used to vertically project points downward onto the pile cap, which comprises:

[0013] Installing an aerial total station on the inner wall of the top end of each tower limb of the bridge tower pier, and enabling the aerial total station to vertically project points onto the pile cap;

[0014] Vertically projecting points from the aerial total station onto the pile cap.

[0015] In some optional schemes, when installing the aerial total station on the inner wall of the top end of each tower limb of the bridge tower pier, an attached footrest is first installed on the inner wall of the top end of each tower limb of the bridge tower pier, and then the aerial total station is installed on the attached footrest, so that the aerial total station can vertically project points onto the pile cap.

[0016] In some optional schemes, the measurement of the projection points of each aerial total station to obtain the observation coordinates of each projection point comprises:

[0017] Setting a ground total station on the center control point of the pile cap, and enabling the ground total station to view the ground control point on the bridge center line;

[0018] Using the ground total station to measure each of the projection points to obtain the observation coordinates of each of the projection points.

[0019] In some alternative schemes, the establishment of an aerial geodetic polygon network centered on each aerial total station, and the measurement of the observed side length between every two vertices of each aerial geodetic polygon network using the aerial total station, includes:

[0020] Connect the centers of the aerial total station located at the top of adjacent towers to form an aerial geodetic polygon network;

[0021] The observed side lengths between every two vertices of the aerial geodetic polygon network are obtained by measuring each other with various aerial total stations.

[0022] In some alternative schemes, determining the coordinates of the aerial total station based on the observed coordinates of each projection point and the observed side length between every two vertices of the aerial geodetic polygon network includes:

[0023] Based on the observed side length between every two vertices of the aerial geodetic polygon network, and combined with the observed coordinates of each projection point, the observed coordinates of each projection point are corrected to obtain the coordinates of the aerial total station.

[0024] Based on the coordinates from the aerial total station, an aerial control network for the bridge tower piers was established.

[0025] In some alternative schemes, the process of correcting the observed coordinates of each projection point based on the observed side length between every two vertices of the aerial geodetic polygon network and the observed coordinates of each projection point to obtain the coordinates of the aerial total station includes:

[0026] Based on the observed coordinates of each projection point, determine the calculated side length between the corresponding projection points of the total station at the top of each two tower limbs;

[0027] Based on the calculated side length between the corresponding projection points of the aerial total station at the top of each two tower limbs and the observed side length between each two vertices of the aerial geodetic polygon network, the aerial geodetic polygon network is adjusted to obtain the adjusted values ​​of each side length of the aerial geodetic polygon network.

[0028] Based on the adjustment values ​​of each side length of the aerial geodetic polygon network, the observed coordinates of each projection point are corrected to obtain the coordinates of the aerial total station.

[0029] In some alternative schemes, the mean correction method is used when correcting the observed coordinates of each projection point based on the adjustment values ​​of the aerial geodetic polygon network.

[0030] In some alternative designs, the bridge pier comprises four tower legs.

[0031] In some alternatives, the aerial total station is a hollow vertical axis total station.

[0032] Compared with existing technologies, the advantages of this invention are as follows: This scheme first sets up an aerial total station at the top of the tower, projecting its vertical center onto the foundation platform to direct surveyors at the foundation platform to establish control points. The coordinates of the center of the hollow vertical axis total station at the top of the tower are obtained by measuring the coordinates of these control points. Prioritizing the installation of the hollow vertical axis total station in the complex and confined construction area at the top of the tower, and projecting its center vertically onto the foundation platform, allows surveyors at the foundation platform, where there is less construction interference and a larger working area, to establish and measure points. This reverse transmission of the ground measurement benchmark to the air overcomes the shortcomings of the "bottom-up" zenith projection method for transmitting the measurement benchmark, making it more suitable for multi-tower, multi-point projection measurements and significantly improving measurement efficiency. The zenith projection method, involving multiple tower sections and multiple points, reversely transmits the ground measurement benchmark to the air, facilitating multi-point cross-checking and ensuring the accuracy and reliability of the measurement benchmark transmission. Attached Figure Description

[0033] 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.

[0034] Fig. 1 This is a flowchart of the aerial control network layout method for multi-tower bridge piers in an embodiment of the present invention;

[0035] Fig. 2 This is a schematic diagram illustrating the principle of control network deployment in an embodiment of the present invention;

[0036] Fig. 3 This is a schematic diagram of an aerial total station installed on a tower leg in an embodiment of the present invention.

[0037] In the diagram: 1. Aerial total station; 2. Attached tripod; 3. Tower leg; 4. Foundation; 5. Aerial geodetic polygon network. Detailed Implementation

[0038] 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.

[0039] like Figs. 1-3 As shown in the accompanying drawings, the embodiments of the present invention will be further described in detail below.

[0040] This invention provides a method for deploying an aerial control network for multi-tower bridge piers, comprising the following steps:

[0041] S1: Use the aerial total station 1 installed on the inner wall of the top of each tower leg 3 of the bridge tower pier to vertically project the point downwards onto the pier cap 4.

[0042] To facilitate the establishment of an aerial control network, a total station 1 is installed on the inner wall of the top of each tower limb 3 and vertically projected downwards onto the foundation 4 to achieve a line-of-sight effect.

[0043] Step S1 specifically includes:

[0044] S11: Install an aerial total station 1 on the inner wall of the top of each tower leg 3 of the bridge pier, and make the aerial total station 1 able to be vertically projected onto the pier cap 4.

[0045] In this example, when installing the aerial total station 1 on the inner wall of the top of each tower member 3 of the bridge tower pier, first install the attached tripod 2 on the inner wall of the top of each tower member 3 of the bridge tower pier, and then install the aerial total station 1 on the attached tripod 2 so that the aerial total station 1 can be vertically projected onto the pier cap 4.

[0046] This setup allows the aerial total station 1 to be vertically projected onto the foundation 4 without being obstructed by other construction lines of sight.

[0047] S12: Project the total station 1 vertically onto the foundation 4.

[0048] In this example, the aerial total station 1 is a hollow vertical axis total station, which can vertically project points from the top of tower limb 3 onto the foundation 4, transferring the coordinates of the top of tower limb 3 to the foundation 4. The vertical points projected by aerial total station 1 onto the foundation 4 are TZ. i , where i = 1...n, and n is the number of tower limbs 3.

[0049] S2: Measure the projection points of each aerial total station 1 to obtain the observation coordinates of each projection point.

[0050] In some optional embodiments, step S2 includes:

[0051] S21: Set up a ground total station at the center control point of pier cap 4, and make the ground total station backsight the ground control point located on the centerline of the bridge.

[0052] S22: Use a ground total station to measure each of the projection points to obtain the observation coordinates of each projection point.

[0053] Specifically, the observation coordinates of each of the aforementioned projection points That is, the center TZ of each hollow vertical axis total station. i ′ Observation coordinates

[0054] S3: Establish an aerial geodetic polygon network 5 with the center of each aerial total station 1, and use the aerial total station to measure and obtain the observed side length between each pair of vertices of the aerial geodetic polygon network 5.

[0055] Step S3 includes:

[0056] S31: Connect the centers of the aerial total station 1 placed at the top of the adjacent tower limb 3 to form an aerial geodetic polygon network 5.

[0057] S32: Use each aerial total station 1 to measure each other and obtain the observed side length between every two vertices of the aerial geodetic polygon network 5.

[0058] In this example, the observed side lengths between every two vertices of the aerial geodetic polygon network 5 are obtained by using aerial total stations 1 located at each vertex of the aerial geodetic polygon network 5 to measure each other. i and j are both 1...n, where n is the number of tower legs 3, and i ≠ j.

[0059] In this example, the bridge pier includes four tower legs 3, that is, four aerial total stations 1 are set at the top of the four tower legs 3 to form an aerial geodetic quadrilateral network, n=4.

[0060] S4: Based on the observed coordinates of each projection point and the observed side length between every two vertices of the aerial geodetic polygon network 5, determine the coordinates of the aerial total station 1 and establish the aerial control network for the bridge tower piers.

[0061] Based on the above embodiments, step S4 includes:

[0062] S41: Based on the observed side length between every two vertices of the aerial geodetic polygon network 5, and combined with the observed coordinates of each projection point, the observed coordinates of each projection point are corrected to obtain the coordinates of the aerial total station 1.

[0063] Step S41 includes:

[0064] S411: Based on the observed coordinates of each projection point, determine the calculated side length between the corresponding projection points of the total station 1 at the top of each pair of tower legs 3.

[0065] Observation coordinates of each projection point That is, the center TZ of each hollow vertical axis total station. i ′ Observation coordinates By calculating the distance between each pair of tower legs, the calculated side length between the corresponding projection points of the total station at the top of each pair of tower legs 3 can be obtained.

[0066] S412: Based on the calculated side length between the corresponding projection points of the aerial total station 1 at the top of each pair of tower legs 3 and the observed side length between each pair of vertices of the aerial geodetic polygon network 5, the aerial geodetic polygon network is adjusted to obtain the adjusted values ​​of each side length of the aerial geodetic polygon network 5.

[0067] In this example, the adjustment values ​​of the side lengths of the aerial geodetic polygon network 5 are... That is, the adjusted length between every two vertices of the aerial geodetic polygon network 5.

[0068] S413: Based on the adjustment values ​​of the side lengths of the aerial geodetic polygon network 5, the observation coordinates of each projection point are corrected to obtain the coordinates of the aerial total station 1.

[0069] When correcting the observation coordinates of each projection point based on the adjustment values ​​of the aerial geodetic polygon network 5, the mean correction method is used.

[0070] Specifically, based on the adjustment values ​​of each pair of side lengths of the aerial geodetic polygon network. That is, the adjustment value of the length between two vertices of the aerial geodetic polygon network 5. Calculated side length between the points projected by the total station 1 at the top of the two tower legs 3 and the corresponding points of the two tower legs 3. The difference between the two points and the azimuth angle of the line connecting them are used to determine the hollow vertical axis total station center TZ corresponding to the two vertices of the aerial geodetic polygon network 5. i ′ and TZ j ′ Observation coordinates and Average corrections were performed. Aerial network adjustment was employed, eliminating errors from the transfer of multi-point measurement benchmarks, improving the accuracy of aerial control points, and ensuring precise measurement of the spatial geometric relationships between multiple tower sections.

[0071] S42: Establish an aerial control network for the bridge tower piers based on the coordinates of the total station 1.

[0072] In this example, the central adjustment coordinates of each hollow vertical axis total station are obtained by correcting according to the above correction method, that is, the coordinates of the aerial total station 1, so that the aerial control network of the bridge tower pier can be established.

[0073] In another embodiment, in step S1, a laser plumb bob + total station is used instead of a hollow vertical axis total station. First, attached scaffolds are installed on the inner walls of the top of each tower leg of the bridge pier. Then, the laser plumb bob is installed on the attached scaffolds so that the laser plumb bob can project points vertically onto the pier platform. Then, the laser plumb bob is removed and a total station is installed in its place. In steps S2 to S4, the projection coordinates of the laser plumb bob and the observation side length of the total station are used to establish an aerial control network for the bridge pier.

[0074] In summary, this scheme employs a "top-down" hollow vertical axis total station nadir projection measurement method: First, a hollow vertical axis total station is set up at the top of the tower (the upper part of the bridge tower pier), directing surveyors at the base of the tower to establish control points. The coordinates of the center of the hollow vertical axis total station at the top of the tower are obtained by measuring the coordinates of the control points at the base of the tower. This method prioritizes setting up the hollow vertical axis total station in the complex and confined construction area at the top of the tower, projecting its center vertically onto the base of the tower. Then, surveyors at the base of the tower, where there is less construction interference and a larger working area, are directed to establish and measure points. This reverse process transfers the ground measurement benchmark to the air, overcoming the shortcomings of the "bottom-up" nadir projection method in transferring the measurement benchmark. This method is more suitable for multi-tower, multi-point projection measurements, significantly improving measurement efficiency.

[0075] The method employs a nadir projection surveying approach, projecting data from multiple towers at multiple points. This reverse transmission of the ground-based measurement benchmark to the air facilitates cross-checking between multiple points, ensuring the accuracy and reliability of the benchmark transfer. Aerial network establishment and adjustment eliminates errors in the transfer of multi-point measurement benchmarks, improving the accuracy of the aerial control network points and guaranteeing precise measurement of the spatial geometric relationships between multiple towers. The use of an auxiliary device—a hollow vertical axis total station with its handle center prism—makes aerial control network observation fast and convenient.

[0076] 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.

[0077] 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.

[0078] 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 method for deploying an aerial control network for multi-tower bridge piers, characterized in that, Includes the following steps: Using an aerial total station (1) installed on the inner wall of the top of each tower leg (3) of the bridge tower pier, vertically project the point downwards onto the pier cap (4); The projection points of each aerial total station (1) were measured to obtain the observation coordinates of each projection point, including: Set up a ground total station at the center control point of the pier cap (4) and make the ground total station backsight the ground control point located on the center line of the bridge; The observation coordinates of each projection point were obtained by measuring each projection point using a ground total station. An aerial geodetic polygon network (5) is established with the center of each aerial total station (1). Using the aerial total station, the observed side lengths between every two vertices of the aerial geodetic polygon network (5) are obtained, including: Connect the centers of the aerial total station (1) placed at the top of the adjacent tower (3) to form an aerial geodetic polygon network (5). The observation side length between each two vertices of the aerial geodetic polygon network (5) is obtained by measuring each other with the various aerial total stations (1); Based on the observed coordinates of each projection point and the observed side length between every two vertices of the aerial geodetic polygon network (5), the coordinates of the aerial total station (1) are determined, and the aerial control network for the bridge tower piers is established, including: Based on the observed side lengths between every two vertices of the aerial geodetic polygon network (5), and combined with the observed coordinates of each projection point, the observed coordinates of each projection point are corrected to obtain the coordinates of the aerial total station (1), including: Based on the observation coordinates of each projection point, determine the calculated side length between the corresponding projection points of the total station (1) at the top of each two tower legs (3); Based on the calculated side length between the corresponding projection points of the aerial total station (1) at the top of each two tower legs (3) and the observed side length between each two vertices of the aerial geodetic polygon network (5), the aerial geodetic polygon network is adjusted to obtain the adjusted values ​​of each side length of the aerial geodetic polygon network (5). Based on the adjustment values ​​of the side lengths of the aerial geodetic polygon network (5), the observation coordinates of each projection point are corrected to obtain the coordinates of the aerial total station (1); Based on the coordinates of the total station (1), an aerial control network for the bridge tower piers is established.

2. The method for deploying the aerial control network for multi-tower bridge piers as described in claim 1, characterized in that: The method of using an aerial total station (1) installed on the inner wall of the top of each tower leg (3) of the bridge tower pier to vertically project points onto the pier platform includes: An aerial total station (1) is installed on the inner wall of the top of each tower leg (3) of the bridge tower pier, and the aerial total station (1) can be vertically projected onto the pier cap (4). Make the total station (1) in the air drop vertically onto the pier (4).

3. The method for laying out the aerial control network for multi-tower bridge piers as described in claim 2, characterized in that: When installing an aerial total station (1) on the inner wall of the top of each tower leg (3) of the bridge tower pier, first install an attached tripod (2) on the inner wall of the top of each tower leg (3) of the bridge tower pier, and then install the aerial total station (1) on the attached tripod (2) so that the aerial total station (1) can be vertically projected onto the pier cap (4).

4. The method for laying out the aerial control network for multi-tower bridge piers as described in claim 1, characterized in that, When correcting the observation coordinates of each projection point based on the adjustment value of the aerial geodetic polygon network (5), the mean value correction method is used.

5. The method for laying out the aerial control network for multi-tower bridge piers as described in claim 1, characterized in that, The bridge pier includes four tower legs (3).

6. The method for laying out the aerial control network for multi-tower bridge piers as described in claim 4, characterized in that, The aerial total station (1) is a hollow vertical axis total station.

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