Four-point initial positioning measurement method for self-balancing cross anchoring and mixed anchoring cable conduit construction

Abstract

The invention discloses a four-point initial positioning measurement method for self-balancing cross anchoring and mixed anchoring cable guide pipe construction. A four-point initial positioning method is adopted; inputting any elevation into an Excel calculation program through the Excel calculation program, inputting the number of the cable guide pipe, setting out any elevation of a tower outlet and an upper opening of the cable guide pipe, and controlling the initial positioning accuracy of the cable guide pipe within 2cm; lofting a side line point of the template by using any elevation calculation program for controlling the position of the cable conduit groove and preventing the diagonal plane of the cable conduit tower outlet from twisting; the follow-up accurate positioning and mounting speed of the cable guide pipe is high, so that the accurate positioning of the cable guide pipe only needs 10-15 minutes, and the positioning speed of the cable guide pipe can be increased. And initial positioning measurement of the cable conduit can be carried out in the daytime, so that the construction efficiency is greatly improved, and the positioning precision of the cable conduit is ensured to meet the standard requirements.

Description

Technical Field

[0001] This invention relates to the field of measurement technology for cable-stayed bridge cable duct construction, and in particular to a four-point initial positioning measurement method for self-balancing cross-anchoring and hybrid anchoring cable duct construction. Background Technology

[0002] Cable-stayed / suspension bridges are the mainstream form of long-span bridges, and the cable guide tube is the core component for cable anchorage. The measurement accuracy of the cable guide tube directly affects the structural safety and service life. Traditional anchorage technologies mainly adopt the following single anchorage methods:

[0003] Cross anchoring: relies on soft traction positioning of steel strands, which has problems such as large deviation in anchor cup insertion and inaccurate control of counter pressure;

[0004] Toothed block anchoring: It is fixed by pre-embedded toothed block structure, but it has poor adaptability to dynamic loads and is prone to displacement of the anchoring end due to compression deformation.

[0005] Furthermore, since the cable guide is anchored by a combination of cross anchoring and toothed block anchoring, 6-9 cable guides need to be positioned and installed in one section of the template. The diameter of each cable guide is different, and a cable guide can be divided into up to 4 sections for positioning and installation. Conventional positioning methods for cable guides are wasteful of manpower and resources, and the process is cumbersome. Moreover, the positioning accuracy requirements for cable guides are high, and the error is difficult to control, which cannot meet the requirements.

[0006] In view of the above difficulties, there is an urgent need to find a safe, efficient method that can guarantee the positioning accuracy of the cable guide tube to solve the problem of cable guide tube positioning. Summary of the Invention

[0007] The purpose of this invention is to provide a four-point initial positioning measurement method for cable conduit construction that can both ensure the accuracy of cable conduit positioning measurement and save and increase effective working time. This method enables subsequent accurate positioning and installation of the cable conduit quickly, thereby accelerating the positioning speed and improving construction efficiency.

[0008] The objective of this invention is achieved as follows:

[0009] A four-point initial positioning measurement method for self-balancing cross-anchoring and hybrid anchoring cable conduits, characterized by the following specific steps:

[0010] (1) Calculation of the cable duct axis:

[0011] The coordinate system of the cable-stayed bridge's ductwork typically uses the bridge's main span axis as the X-axis, the direction perpendicular to the main span as the Y-axis, and the elevation direction as the Z-axis. The origin of the ductwork coordinate system is generally set at the theoretical intersection of the main tower centerline and the main girder. For ease of construction, an independent coordinate system is established along the axial direction of the cable-stayed bridge. This independent coordinate system uses mileage as the x-axis, the transverse direction as the y-axis, the bridge centerline as the origin, and elevation as the z-axis. The mathematical expression for the ductwork axis in three-dimensional space is:

[0012]

[0013] Where: 1. (x0, y0, z0): Design coordinates of the anchorage end (taken from construction drawings), l x ,l y ,l z 1. Direction cosine of the cable guide axis, t: parameter variable (0≤t≤L, L is the length of the cable guide); 2. Calculation of direction cosine, derived from the horizontal deflection angle α and elevation angle β in the design drawings:

[0014] l x =cosα·cosβ

[0015] l y =sinα·cosβ

[0016] l z =sinβ

[0017] Note that the angle unit is always in radians, and you need to convert between degrees, minutes, and seconds when calculating.

[0018] (2) Steps for calculating key coordinate points and determining the coordinates of the anchorage end:

[0019] Calculate the anchorage coordinates based on the (x0, y0, z0) coordinates marked on the construction drawings. Verification method: Based on the design coordinates (x0, y0, z0) of the anchorage end and the coordinates (x1, y1, z1) of the exit point marked on the drawings, calculate the direction cosine and compare the consistency of coordinates between drawings from different disciplines. The exit point coordinates are calculated based on the length L of the cable guide and the direction cosine.

[0020]

[0021] Intermediate control points are densified, and theoretical coordinate points are set at 1m intervals for verification during construction.

[0022] x i =x0+i·ΔL·l x (i = 1, 2, ..., n)

[0023] Where ΔL is the segment length, the influence of cable duct stiffness on segment spacing needs to be considered;

[0024] (3) Coordinate transformation and error control:

[0025] Global coordinate system → Local coordinate system: Achieved through coordinate translation and rotation matrices, formula:

[0026]

[0027] R is the rotation matrix, containing the bridge's longitudinal and transverse slope angle parameters; local is the local coordinate system, (X... local ,Y local Z local The local coordinate system (X) represents the transformed coordinates, directly related to the construction parameters of the component (such as slope and embedded position); the global coordinate system (X) represents the global coordinate system. glocal ,Y glocal Z glocal (x0, y0, z0) represents the coordinates of the point to be transformed in the global system, and (x0, y0, z0) represents the offset of the origin of the local coordinate system in the global system.

[0028] (4) Calculation of arbitrary coordinates of the cable duct:

[0029] Then, using the X and Y coordinates calculated from any elevation point of the cable guide, and based on the elevation Z, direction coefficients (Kx, Ky), and intercept terms (bx, by), the formula is derived as follows:

[0030] X = Kx·Z + bx

[0031] Y = Ky·Z + by

[0032] Where: X: longitudinal bridge coordinate (main span direction), Y: transverse bridge coordinate (perpendicular to the main span direction), Z: elevation coordinate (height above the datum plane), Kx, Ky: direction coefficients (multiplied by constants), bx, by: intercept terms (added by constants);

[0033] (5) Application of Excel calculation program for initial four-point positioning of cable guide:

[0034] The above formulas are integrated into an Excel program, and design parameters are stored in an integrated manner. The design parameters corresponding to the cable guide numbers are preset in an Excel parameter table. The VLOOKUP function is used to automatically match parameters after the number is entered. The reference coordinates and slope parameters corresponding to the cable guide numbers are pre-entered into an Excel spreadsheet, supporting quick retrieval by number and reducing manual input errors. Reference parameters are linked with one click to avoid duplicate calculations. Design parameters are automatically matched based on any input elevation, and theoretical 3D coordinates are generated in real time without manual derivation. Real-time comparison of measured data: After inputting any measured elevation on site, Excel automatically compares the theoretical coordinates with the measured values, generating offset and deviation direction. The allowable deviation range (e.g., ±5mm) can be set: in case of abnormal deviation ( If the limit is exceeded by more than 10mm, a high-brightness warning (e.g., red fill) is triggered, intuitively indicating that verification or adjustment is required; multi-source data cross-validation: the positioning step list (e.g., cable duct diameter, design elevation) is automatically output based on the cable duct number, reducing manual decision-making steps; built-in data verification function to check for input value format errors (e.g., incorrect elevation units, incorrect slope symbols); templated process: a standardized input interface guides users to operate step by step (number → input elevation → obtain results), lowering the operation threshold; key parameter locking protection (e.g., reference coordinate system) to prevent accidental deletion or tampering; intelligent fault tolerance mechanism, automatically intercepting and prompting when an unreasonable elevation is input (e.g., negative value or exceeding the design range); missing parameters (e.g., unentered cable duct number) trigger a pop-up window to guide the completion of information;

[0035] (6) Initial positioning of the cord catheter:

[0036] On the rigid frame, input any elevation into the Excel calculation program, input the cable guide number, and lay out the coordinates of the cable guide bottom outlet and the coordinates of any elevation point at the top of the cable guide. Similarly, lay out two template edge points (main tower template edge points, used to control the section position of the cable guide and avoid twisting of the cable guide's oblique cut surface) on the cable guide outlet positioning fixture. The four points—the tower outlet coordinates, the arbitrary elevation coordinates of the cable guide's top opening, and the two template edge points—ensure that the initial installation accuracy of the cable guide can reach within 2cm of the three-dimensional coordinate deviation. On-site, weld the fixture according to the initial positioning of the cable guide, including the support structure and sliding adjustment system; (fixture accuracy requirements: horizontal adjustment range ±50mm, vertical fine adjustment accuracy ±30mm) for fine adjustment after cable guide installation.

[0037] Compared with the prior art, the advantages of the present invention are as follows:

[0038] 1. This invention adopts the "four-point initial positioning method" to control the initial positioning of the cable guide within 2cm. The initial positioning measurement of the cable guide can be carried out during the day, which makes the subsequent precise positioning and installation of the cable guide faster. Thus, the precise positioning of the cable guide only takes 10-15 minutes per section, which can speed up the positioning speed of the cable guide, greatly improve the construction efficiency, and at the same time ensure that the positioning accuracy of the cable guide meets the specification requirements.

[0039] 2. The application of the cable guide Excel calculation program integrates and stores design parameters, supports quick retrieval by number, and reduces manual input errors; it automatically matches design parameters based on any input elevation and generates theoretical 3D coordinates in real time without manual derivation; it allows for instant comparison of measured data, reducing manual decision-making and lowering the operational threshold.

[0040] This invention is not limited to applications in cable conduit positioning measurements; it is equally applicable to any positioning construction measurements similar to this invention. Attached Figure Description

[0041] Figure 1 This is a flowchart of the present invention;

[0042] Figure 2 A schematic diagram of the Excel calculation program for the initial four-point positioning of the cable guide tube;

[0043] Figure 3 A schematic diagram of the cable conduit location;

[0044] Figure 4 A frontal view of the cable guide point;

[0045] Figure 5 A side view of the location of the cable guide point;

[0046] Figure 6 Schematic diagram of the positioning fixture for the cable guide tube outlet of the tower;

[0047] Figure 7 A schematic diagram of the cable guide adjustment fixture. Detailed Implementation

[0048] The present invention will now be described in further detail with reference to the embodiments and the accompanying drawings.

[0049] A four-point initial positioning measurement method for self-balancing cross-anchoring and hybrid anchoring cable conduits. The specific implementation steps are as follows:

[0050] (1) Calculation of the cable duct axis:

[0051] The coordinate system of the cable-stayed bridge's ductwork typically uses the bridge's main span axis as the X-axis, the direction perpendicular to the main span as the Y-axis, and the elevation direction as the Z-axis. The origin of the ductwork coordinate system is generally set at the theoretical intersection of the main tower centerline and the main girder. For ease of construction, an independent coordinate system is established along the axial direction of the cable-stayed bridge. This independent coordinate system uses mileage as the x-axis, the transverse direction as the y-axis, the bridge centerline as the origin, and elevation as the z-axis. The mathematical expression for the ductwork axis in three-dimensional space is:

[0052]

[0053] Where: 1. (x0, y0, z0): Design coordinates of the anchorage end (taken from construction drawings), l x ,l y ,l z 1. Direction cosine t of the cable guide axis: Parameter variable (0≤t≤L, L is the length of the cable guide) 2. Calculation of direction cosine, derived from the horizontal deflection angle α and elevation angle β in the design drawings:

[0054] l x =cosα·cosβ

[0055] l y =sinα·cosβ

[0056] l z =sinβ

[0057] Note that the angle unit is always in radians, and you need to convert between degrees, minutes, and seconds when calculating.

[0058] (2) Steps for calculating key coordinate points and determining the coordinates of the anchorage end:

[0059] Calculate the anchorage coordinates based on the (x0, y0, z0) coordinates marked on the construction drawings. Verification method: Based on the design coordinates (x0, y0, z0) of the anchorage end and the coordinates (x1, y1, z1) of the exit point marked on the drawings, calculate the direction cosine and compare the consistency of coordinates between drawings from different disciplines. The exit point coordinates are calculated based on the length L of the cable guide and the direction cosine.

[0060]

[0061] Intermediate control points are densified, and theoretical coordinate points are set at 1m intervals for verification during construction.

[0062] x i =x0+i·ΔL·l x (i = 1, 2, ..., n)

[0063] Where ΔL is the segment length, the influence of cable duct stiffness on segment spacing needs to be considered;

[0064] (3) Coordinate transformation and error control:

[0065] Global coordinate system → Local coordinate system: Achieved through coordinate translation and rotation matrices, formula:

[0066]

[0067] R is the rotation matrix, containing the bridge's longitudinal and transverse slope angle parameters; local is the local coordinate system, (X... local ,Y local Z local The ) represents the transformed local coordinates, directly associated with component construction parameters (such as slope and embedded position); global represents the global coordinate system, (X) glocal ,Y glocal Z glocal (x0, y0, z0) represents the coordinates of the point to be transformed in the global system, and (x0, y0, z0) represents the offset of the origin of the local coordinate system in the global system.

[0068] (4) Calculation of arbitrary coordinates of the cable duct:

[0069] The X and Y coordinates are calculated from any elevation point of the cable duct and derived based on the elevation Z, direction coefficients (kx, ky), and intercept term (bx, by). The formula is:

[0070] X = Kχ·Z + bχ

[0071] Y = Ky·Z + by

[0072] Where: X: longitudinal bridge coordinate (main span direction), Y: transverse bridge coordinate (perpendicular to the main span direction), Z: elevation coordinate (height above the datum plane), Kx, Ky: direction coefficients (multiplied by constants), bx, by: intercept terms (added by constants);

[0073] (5) Application of Excel calculation program for initial four-point positioning of cable guide:

[0074] The above formulas are integrated into an Excel program, and design parameters are stored in an integrated manner. The design parameters corresponding to the cable guide number are preset in the Excel parameter table. The VLOOKUP function is used to automatically match parameters after the number is entered. The benchmark coordinates and slope parameters corresponding to the cable guide number are pre-entered into an Excel spreadsheet, supporting quick retrieval by number and reducing manual input errors. Benchmark parameters are linked with one click to avoid duplicate calculations. Design parameters are automatically matched based on any input elevation, and theoretical 3D coordinates are generated in real time without manual derivation. Real-time comparison of measured data: After inputting any measured elevation on site, Excel automatically compares the theoretical coordinates with the measured values, generating offset and deviation direction. A deviation allowable range (e.g., ±5mm) is set: When there is an abnormal deviation (e.g., exceeding the limit > 10mm), a highlight warning is triggered (e.g., red fill), intuitively indicating that a review or adjustment is needed. Multi-source data cross-validation: The positioning step list (e.g., cable guide diameter, design elevation) is automatically output based on the cable guide number, reducing manual decision-making steps. Built-in data validation function to check for input value format errors (such as incorrect elevation units or slope signs); templated workflow: standardized input interface guides users through the steps (number → input elevation → obtain results), lowering the operational threshold. Key parameters are locked and protected (such as the reference coordinate system) to prevent accidental deletion or tampering. Intelligent fault tolerance mechanism automatically intercepts and prompts when unreasonable elevations are input (such as negative values ​​or values ​​exceeding the design range). Missing parameters (such as an unentered cable guide number) trigger a pop-up window to guide the completion of information.

[0075] (6) Initial positioning of the cord catheter:

[0076] On the rigid frame 7 Figure 2 The Excel calculation program is used to input arbitrary elevations and cable guide duct numbers. The program then lays out the three-dimensional coordinates of the cable guide duct exit point 1, comparing them with the theoretical design coordinates until the design coordinates are obtained, and marking them. Similarly, using the calculation program, the coordinates of the arbitrary elevation point 2 at the top of the cable guide duct are laid out based on actual measurements, and marked accordingly. The cable guide exit positioning fixture 5 is installed on both sides close to the cable guide duct's cross-section. The arbitrary elevation calculation program is used to lay out template edge points 3 and 4 to control the cable guide duct's cross-section position and prevent twisting of the cable guide duct's oblique cross-section. The three-dimensional coordinates (K) at any elevation of the pier body are then calculated. H ,Y H Z H The calculation formula is:

[0077]

[0078] in The ratio of longitudinal horizontal offset to elevation; The ratio of lateral horizontal offset to elevation; H = Z H-Z0: Elevation difference between the point to be calculated and the center of the pier bottom surface; these four points ensure that the initial installation accuracy of the cable guide can reach within 2cm of the three-dimensional coordinate deviation. The initial positioning of the cable guide can be carried out during the day, unaffected by the weather. On-site, the adjustment fixture 6, including the support structure and sliding adjustment system, is welded according to the initial positioning of the cable guide. ( Fixture accuracy requirements: horizontal adjustment range ±50mm, vertical fine adjustment accuracy ±30mm) is used for fine adjustment after the cable guide is installed.

[0079] Compared with conventional cable guide pipe positioning measurements, traditional methods have limitations: strong time dependence (traditional total station cable guide pipe positioning requires avoiding strong light interference (especially midday), relying on nighttime or cloudy days for operation); significant environmental constraints (direct sunlight weakens the prism reflection signal, increasing measurement errors); and forced extension of the construction period (the effective working window is only 4-6 hours per day, affecting construction continuity). In contrast, the "four-point initial positioning method" achieves initial installation accuracy of the cable guide pipe within 2cm of three-dimensional coordinate deviation through four-point positioning. Initial positioning of the cable guide pipe can be performed during the day, as well as subsequent installation of tooling and the cable guide pipe, without affecting construction continuity. This significantly improves the efficiency of cable guide pipe measurement, thereby greatly shortening the precision positioning time.

[0080] Although the present invention has been disclosed above, it is not limited thereto. For example, the positioning and measurement of the bracket next to the pier can be used. Any person skilled in the art can make various modifications and alterations without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope defined in the claims.

Claims

1. A four-point initial positioning measurement method for the construction of self-balancing cross-anchoring and hybrid anchoring cable guides, characterized in that: The specific steps are as follows: (1) Calculation of the cable duct axis: The coordinate system of the cable-stayed bridge's ductwork typically uses the bridge's main span axis as the X-axis, the direction perpendicular to the main span as the Y-axis, and the elevation direction as the Z-axis. The origin of the ductwork coordinate system is generally set at the theoretical intersection of the main tower centerline and the main girder. For ease of construction, an independent coordinate system is established along the axial direction of the cable-stayed bridge. This independent coordinate system uses mileage as the x-axis, the transverse direction as the y-axis, the bridge centerline as the origin, and elevation as the z-axis. The mathematical expression for the ductwork axis in three-dimensional space is: Where:

1. (x0, y0, z0): Design coordinates of the anchorage end, l x ,l y ,l z 1. Direction cosine of the cable guide axis, t: parameter variable 0≤t≤L, where L is the length of the cable guide; 2. Calculation of direction cosine, derived from the horizontal deflection angle α and elevation angle β in the design drawings: l x = cosα·cosβ l y =sinα·cosβ the z =sinβ Note that the angle unit is always in radians, and you need to convert between degrees, minutes, and seconds when calculating. (2) Steps for calculating key coordinate points and determining the coordinates of the anchorage end: Calculate the anchorage coordinates based on the (x0, y0, z0) coordinates marked on the construction drawings. Verification method: Based on the design coordinates (x0, y0, z0) of the anchorage end and the coordinates (x1, y1, z1) of the exit point marked on the drawings, calculate the direction cosine and compare the consistency of coordinates between drawings from different disciplines. The exit point coordinates are calculated based on the length L of the cable guide and the direction cosine. Intermediate control points are densified, and theoretical coordinate points are set at 1m intervals for verification during construction. x i = x0+i·ΔL·l x (i=1,2,…,n) Where ΔL is the segment length, the influence of cable duct stiffness on segment spacing needs to be considered; (3) Coordinate transformation and error control: Global coordinate system → Local coordinate system: Achieved through coordinate translation and rotation matrices, formula: R is the rotation matrix, containing the bridge's longitudinal and transverse slope angle parameters; local is the local coordinate system, (X... local ,Y local Z local () represents the transformed local coordinates, directly related to the construction parameters of the component; global represents the global coordinate system, (X... glocal ,Y glocal Z glocal (x0, y0, z0) represents the coordinates of the point to be transformed in the global system, and (x0, y0, z0) represents the offset of the origin of the local coordinate system in the global system. (4) Calculation of arbitrary coordinates of the cable duct: Then, using the X and Y coordinates calculated from any elevation point of the cable guide, and based on the elevation Z, direction coefficients (Kx, Ky), and intercept terms (bx, by), the formula is derived as follows: X = Kx·Z + bχ Y = Ky·Z + by Where: X: longitudinal bridge coordinate, Y: transverse bridge coordinate, Z: elevation coordinate, Kx, Ky: direction coefficient bx, by: intercept term; (5) Application of Excel calculation program for initial four-point positioning of cable guide: The above formulas are integrated into an Excel program, and the design parameters are stored in an integrated manner. The design parameters corresponding to the cable guide numbers are preset in the Excel parameter table. The VLOOKUP function is used to automatically match the parameters after the number is entered. The benchmark coordinates and slope parameters corresponding to the cable guide numbers are pre-entered into the Excel table, which supports quick retrieval by number and reduces manual input errors. The benchmark parameters are linked with one click to avoid repeated calculations. The design parameters are automatically matched according to any input elevation, and theoretical 3D coordinates are generated in real time without manual derivation. Real-time comparison of measured data: After inputting any measured elevation on site, Excel automatically compares the theoretical coordinates with the measured values ​​and generates the offset and deviation direction. The allowable deviation range is set: abnormal deviations trigger a highlight warning, which intuitively prompts that a review or adjustment is needed. Multi-source data cross-validation: The positioning step list is automatically output according to the cable guide number to reduce the manual decision-making process. The built-in data verification function checks for input value format errors. The templated process: The standardized input interface guides users to operate step by step, reducing the operation threshold. Key parameters are locked and protected to prevent accidental deletion or tampering. The intelligent fault tolerance mechanism automatically intercepts and prompts when an unreasonable elevation is entered. Missing parameters trigger a pop-up window to guide the completion of information. (6) Initial positioning of the cord catheter: On the rigid frame, an arbitrary elevation is entered into the Excel calculation program. The cable guide number is entered, and the coordinates of the cable guide bottom outlet and the coordinates of the arbitrary elevation point of the cable guide top are laid out. Similarly, two template edge points are laid out on the cable guide outlet positioning fixture. The four points—the tower outlet coordinates, the arbitrary elevation coordinates of the cable guide top, and the two template edge points—ensure that the initial installation accuracy of the cable guide can reach within 2cm of the three-dimensional coordinate deviation. On-site, the fixture, including the support structure and sliding adjustment system, is welded according to the initial positioning of the cable guide.

2. The four-point initial positioning measurement method for self-balancing cross-anchoring and hybrid anchoring cable conduit construction according to claim 1, characterized in that: In step (6), the arbitrary elevation is input into the Excel calculation program on the stiffening frame, the cable guide number is input, the three-dimensional coordinates of the cable guide outlet of the tower are laid out, and the theoretical coordinates are compared with the design coordinates until the design coordinates are laid out and marked. Using the same calculation program, the three-dimensional coordinates of the top opening of the cable guide were laid out by measuring any elevation, and the coordinates were marked accordingly. Positioning fixtures are installed on both sides of the cross-section close to the cable guide pipe. The template edge points are then laid out using an arbitrary elevation calculation program to control the position of the cable guide pipe cutout and prevent twisting of the cable guide pipe's oblique cut surface at the tower exit. The three-dimensional coordinates (K...) at any elevation of the pier body... H ,Y H Z H The calculation formula is: in The ratio of longitudinal horizontal offset to elevation; The ratio of lateral horizontal offset to elevation; H = Z H -Z0: The elevation difference between the point to be calculated and the center of the pier bottom surface; These four points ensure that the initial installation accuracy of the cable guide can reach within 2cm of the three-dimensional coordinate deviation. The initial positioning of the cable guide can also be carried out during the day, unaffected by the weather. On-site, the adjustment fixtures, including the support structure and sliding adjustment system, are welded according to the initial positioning of the cable guide.

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