A precise installation method for cable-stayed bridge main beam cable guide

Abstract

The present invention provides a method for accurately installing cable guide tubes for the main beam of a cable-stayed bridge, comprising the following steps: laying out the perforation positions for the cable guide tubes on a template and opening square notches at corresponding positions on the template; welding a cable guide tube placement platform A to the template, measuring and laying out the coordinates of both sides of the cable guide tube's bottom anchor pad; manually hoisting the cable guide tube with a tower crane so that the two corners of the cable guide tube's bottom anchor pad coincide with the coordinate point markings; installing an axis centering tool C at the cable guide tube's upper pipe opening, adjusting the upper pipe opening's position up and down using a total station and the axis centering tool to complete alignment; installing a cable guide tube's rigid skeleton steel support, pressing the cable guide tube anchor pad's steel plate against the notch in the template, and pinning the four corners with steel bar pins. The present invention innovatively introduces a three-point positioning method, first creating a predetermined elevation plane in the spatial structure, determining two coordinate points on this plane, and then determining the third point in space with the aid of the tool, greatly improving the accuracy of the layout.

Description

Technical Field

[0001] The present invention mainly relates to the technical field related to cable-stayed bridge construction, and in particular to a method for accurately installing a cable guide tube of a main beam of a cable-stayed bridge. Background Art

[0002] With the accelerated pace of high-speed railway construction, cable-stayed and suspension bridges are increasingly being used to cross major rivers. Cables, as load-distributing systems, have a direct impact on the safe operation of the structure due to their installation quality. Cable guides, crucial pre-embedded structures at the ends of beams, guide the cables through the beams and anchor them to the beams. Their installation angle and position directly influence the mechanical transmission of the cables and the loads on the beams, making them a crucial component of the pre-embedded cable-stayed bridge system. The research and implementation of methods for precise positioning and rapid installation of cable guides has addressed the challenges of high precision requirements, difficult spatial layout, and the significant impact of complex on-site working conditions in cable guide positioning and installation.

[0003] While several groups have summarized methods for cable conduit installation, most focus on solving the installation problem, with little research on improving installation accuracy and speed. If the layout is inaccurate, the force exerted on the cables can cause biased pressure on the conduit, impacting the overall load of the cables, beams, and towers. This can also lead to significant rework costs later on. Therefore, the precise and efficient installation of cable conduits directly impacts operational safety and corporate reputation. Summary of the Invention

[0004] To address the shortcomings of current technology, the present invention combines existing technologies and, based on practical applications, provides a method for the precise installation of cable guide tubes for the main beam of a cable-stayed bridge. It innovatively introduces a three-point positioning method, first creating a predetermined elevation plane in the spatial structure, determining two coordinate points on the plane, and then determining the third point in space with the assistance of tooling, thereby greatly improving the layout accuracy.

[0005] To achieve the above object, the technical solution of the present invention is as follows:

[0006] A method for accurately installing a cable guide tube for a main beam of a cable-stayed bridge comprises the following steps:

[0007] S1. Locate the hole position of the cable guide on the template and make a square notch at the corresponding position of the template;

[0008] S2. Weld the cable guide placement platform A on the template, measure and stake out the coordinate points 1 and 2 on both sides of the cable guide bottom anchor plate, and mark them;

[0009] S3. Manually cooperate with the tower crane to lift the cable guide so that the two corners of the cable guide bottom anchor plate coincide with the marks of coordinate point 1 and coordinate point 2;

[0010] S4. Install the axis centering tool C on the upper pipe opening of the cable guide tube. Use the total station and the axis centering tool to adjust the position of the upper pipe opening up and down to complete the alignment.

[0011] S5. Install the cable guide steel frame support, anchor the cable guide bottom anchor plate to the steel plate and press the template notch, and press the four corners with steel bar pressure nails;

[0012] S6. Re-measure the position of the cable guide to complete the installation.

[0013] Furthermore, step S1 specifically includes:

[0014] S11. Based on the design drawings, accurately lay out the perforation positions of the cable guide tube on the template;

[0015] S12. Based on the position and size of the bottom anchor plate of the cable guide tube, a square slot is opened at the corresponding position of the template. The size of the slot is 5 cm larger than the bottom anchor plate, and there is 2.5 cm of movable space on each side of the slot.

[0016] Further, step S2 specifically includes:

[0017] S21. Weld channel steel to the back rib of the formwork below the notch as cable guide placement platform A;

[0018] S22. Determine the lower edge elevation of the cable guide bottom anchor pad based on the layout data;

[0019] S23. Place a gasket B with a thickness of 5mm-2cm on platform A until the top elevation of gasket B is the same as the top elevation of platform A.

[0020] The lower edge elevations of the cable guide bottom anchor pads are consistent. At this time, the gasket B is fixed to the platform A by welding with angle steel.

[0021] Further, step S3 specifically includes:

[0022] S31. Manually cooperate with the tower crane to use the lifting belt to lift the rope guide;

[0023] S32, placing the cable guide tube on the gasket B of the platform A;

[0024] S33. Make the two corners of the cable guide bottom anchor plate coincide with the marks of coordinate point 1 and coordinate point 2.

[0025] Further, step S4 specifically includes:

[0026] S41. Orient the upper end of the cable guide tube roughly toward the tower column cable saddle for rough positioning.

[0027] S42. Install the axis centering tool C on the upper end of the cable guide tube and adjust the centering prism on the centering tool C to the center position.

[0028] S43. The total station sets out the center position of the upper pipe opening according to the calculation, providing a spatial line of sight with the crosshairs as the control line;

[0029] S44. Adjust the position of the upper tube opening up and down so that the crosshairs of the total station coincide with the centering prism of tooling C to complete the alignment.

[0030] Further, step S5 specifically includes:

[0031] S51. After the cable guide tube position meets the requirements, the tower crane lifting belt is not removed to maintain the position accuracy;

[0032] S52. Install a "door"-shaped bracket D at the bottom of the cable guide tube. The crossbeam of bracket D supports the cable guide tube. The bottom of bracket D is welded and fixed to the bottom plate reinforcement.

[0033] S53. Install a "door"-shaped bracket E on the upper part of the cable guide tube, covering the cable guide tube. The crossbeam of bracket E presses the cable guide tube. The lower part of bracket E is welded to the bottom plate steel bar.

[0034] S54. Use channel steel to make connecting beam F, clamp the cable guide and connect bracket D and bracket E;

[0035] S55. Anchor the cable guide bottom anchor plate with a steel plate to press the template slot, press the four corners with steel bar pressure nails, and weld the pressure nails to the bottom plate steel bar.

[0036] Further, step S6 specifically includes:

[0037] S61. Re-measure the elevation of the lower edge of the anchor pad at the bottom of the cable guide and coordinate points 1 and 2;

[0038] S62, re-measure the coordinates of the axis center point of the upper pipe opening of the cable guide tube;

[0039] S63. If there is an error between the re-measured data and the design data, continue to make adjustments. If the error with the design value is within the allowable range, remove the lifting belt and complete the positioning installation.

[0040] Beneficial effects of the present invention:

[0041] 1. This installation method innovatively introduces a three-point positioning method for thin-walled cylindrical structures. First, a predetermined elevation plane is created in the spatial structure, two coordinate points are determined on the plane, and then the third point in space is determined with the assistance of tooling, which greatly improves the layout accuracy.

[0042] 2. This installation method breaks the "point-to-point" mode in traditional layout. By adding tooling, the uncertain spatial coordinate points have a definite position. At the same time, the concept of rigid skeleton support is introduced, and the traditional support, pulling and pressing fixing method is changed. A more advanced "locking" installation and fixing method is adopted. Through the three steps of locking elevation, locking corner points and locking axis, each layer is fixed and each step is precise, which greatly speeds up the installation speed.

[0043] 3. This installation method is based on the actual situation of the project site. Except for special small tooling, other equipment, tools and materials used are all readily available materials on the construction site. At the same time, after summary and refinement, it is easy for technical personnel and installers to understand. According to on-site statistics, the installation of each cable conduit can be completed within 2 hours with an error of mm level, which greatly improves the installation accuracy and speed, and achieves good results in social and economic benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Attachment Figure 1 Schematic diagram of cable conduit installation structure Figure 1 .

[0045] Attachment Figure 2 Schematic diagram of cable conduit installation structure Figure 2 .

[0046] Reference numerals shown in the accompanying drawings:

[0047] 1. Platform A; 2. Gasket B; 3. Bottom anchor plate; 4. Coordinate point 1, 5. Coordinate point 2; 6. Cable guide tube; 7. Bracket D; 8. Connecting beam F; 9. Bracket E; 10. Tooling C; 11. Centering prism. DETAILED DESCRIPTION

[0048] The present invention will be further described with reference to the accompanying drawings and specific embodiments. It should be understood that these embodiments are intended only to illustrate the present invention and are not intended to limit the scope of the present invention. In addition, it should be understood that after reading the contents of the present invention, those skilled in the art may make various changes or modifications to the present invention, and these equivalent forms also fall within the scope defined by the present application.

[0049] refer to Figure 1 、 Figure 2 This is a schematic diagram of the status of various components during the precise installation of the cable guide tube of the main beam of the cable-stayed bridge in this embodiment.

[0050] The precise installation method of the cable-stayed bridge main beam cable guide tube of this embodiment mainly includes the following steps.

[0051] (1) Notch at the bottom of the template

[0052] ①According to the design drawings, accurately lay out the perforation position of the cable guide 6 on the template;

[0053] ② The size of the bottom anchor plate 3 of the cable guide tube is different at different positions. A square notch is opened at the corresponding position of the template. Its size is 5 cm larger than the size of the bottom anchor plate 3. There is 2.5 cm of movable space on each side of the notch.

[0054] (2) Installation of cable guide support platform

[0055] ① Weld [16 channel steel on the back rib of the template below the notch as the cable guide placement platform A1;

[0056] ② According to the layout data, determine the elevation of the lower edge of the cable guide bottom anchor plate 3;

[0057] ③ Place a gasket B2 with a thickness of 5mm-2cm on the platform A1 until the top elevation of the gasket B2 is consistent with the lower edge elevation of the cable guide bottom anchor plate 3. At this time, weld the gasket B2 to the platform A1 with angle steel;

[0058] ④ Measure and mark the coordinate points 1 (number 4 in the figure) and 2 (number 5 in the figure) on both sides of the anchor plate 3 at the bottom of the cable guide;

[0059] (3) Cable guide hoisting and positioning

[0060] ① Manually cooperate with the tower crane to use the lifting belt to lift the rope guide 6;

[0061] ② Place the cable guide 6 on the gasket B2 of the platform A1;

[0062] ③ Make the two corners of the cable guide bottom anchor plate 3 coincide with the marks of coordinate point 1 and coordinate point 2;

[0063] (4) Lofting and alignment of the axis of the upper tube end of the cable guide 6

[0064] ① Place the upper end of the cable guide 6 roughly toward the tower cable saddle for rough positioning;

[0065] ② Install the axis centering tool C10 on the upper pipe mouth and adjust the centering prism 11 of the tool C10 to the center position. The tool C10 is mainly installed at the upper pipe mouth and is equipped with a centering prism 11;

[0066] ③ The total station is set out according to the calculated center position of the upper pipe opening, providing a spatial line of sight with the crosshairs as the control line;

[0067] ④ Adjust the position of the upper tube mouth up and down so that the crosshairs of the total station coincide with the centering prism 11 of the tooling C10.

[0068] Complete alignment;

[0069] (5) Installation of cable duct rigid skeleton steel support

[0070] ① After the position of the cable guide 6 meets the requirements, the tower crane lifting belt is not removed to maintain the position accuracy;

[0071] ② Install a "door"-shaped bracket E9 at the bottom of the cable guide 6. The crossbeam of the bracket E9 supports the cable guide 6, and the bottom of the bracket E9 is welded and fixed to the bottom plate steel bar;

[0072] ③ Install a "door"-shaped bracket D7 on the upper part of the cable guide tube, cover the cable guide tube 6, and press the cable guide tube 6 with the crossbeam. The lower part of the bracket D7 is welded and fixed to the bottom plate steel bar;

[0073] ④ Use [16 channel steel as connecting beam F8 to clamp the cable guide 6 and connect bracket D7 and bracket E9;

[0074] ⑤ Anchor the cable guide bottom anchor plate 3 to the steel plate to press the template slot, press the four corners with steel bar pressure nails, and weld the pressure nails to the bottom plate steel bar;

[0075] (6) Re-measure the cable guide position to complete the installation

[0076] ① Re-measure the elevation of the bottom anchor plate 3 of the cable guide and coordinate points 1 and 2;

[0077] ② Re-measure the coordinates of the axis point of the upper tube mouth of the cable guide tube;

[0078] ③ If there is an error between the re-measured data and the design data, continue to adjust. If the error with the design value is within the allowable range, remove the lifting belt and complete the positioning installation.

[0079] This embodiment adopts a one-line, two-point, and one-axis layout method, while introducing a rigid skeleton fixing method. Engineers repeatedly deduced the three processes of layout, hoisting, and fixing until the established goals were met. In actual installation, the installation theory method was continuously optimized and improved. While successfully completing the installation task, a method for precise positioning and rapid installation of the cable guide tube was summarized and proposed. In terms of innovation, this installation method innovatively introduces a three-point positioning method for thin-walled cylindrical structures. First, a predetermined elevation plane is created in the spatial structure, two coordinate points are determined on the plane, and then the third point in space is determined with the assistance of a centering prism tool, which greatly improves the layout accuracy. In terms of advancement, the installation method breaks the "point-to-point" mode in traditional layout, and by adding tooling, the uncertain spatial coordinate points have a definite position. At the same time, the concept of a rigid skeleton bracket is introduced, which changes the traditional support, pull, and press fixing method and adopts a more advanced "locking" method. "Type of installation and fixing method, through the three steps of locking elevation, locking corner points, and locking axis, layer by layer is fixed and step by step is precise, which greatly speeds up the installation speed; in terms of utility model, this installation method is based on the actual situation of the project site. Except for small tooling, other equipment, tools and materials used are all on-site supplies; at the same time, after summary and refinement, it is easy for technical personnel and installers to understand. According to on-site statistics, the installation of each cable conduit can be completed within 2 hours with an error of mm level, which greatly improves the installation accuracy and speed, and achieves good results in social and economic benefits.

Claims

1. A precise installation method for cable-stayed bridge main beam cable guide tube, characterized in that: The steps include: S1. Locate the hole position of the cable guide on the template and make a square notch at the corresponding position of the template; S2. Weld the cable guide placement platform A on the template, measure and stake out the coordinate points 1 and 2 on both sides of the cable guide bottom anchor plate, and mark them; S3. Manually cooperate with the tower crane to lift the cable guide so that the two corners of the cable guide bottom anchor plate coincide with the marks of coordinate point 1 and coordinate point 2; S4. Install the axis centering tool C on the upper pipe opening of the cable guide tube. Use the total station and the axis centering tool to adjust the position of the upper pipe opening up and down to complete the alignment. S5. Install the cable guide steel frame support, anchor the cable guide bottom anchor plate to the steel plate and press the template notch, and press the four corners with steel bar pressure nails; S6. Re-measure the cable catheter position to complete installation; Step S2 specifically includes: S21. Weld channel steel to the back rib of the formwork below the notch as cable guide placement platform A; S22. Determine the lower edge elevation of the cable guide bottom anchor pad based on the layout data; S23. Place a gasket B with a thickness of 5mm-2cm on platform A until the top elevation of gasket B is consistent with the lower edge elevation of the cable guide bottom anchor plate. Then, weld gasket B to platform A using angle steel. Step S3 specifically includes: S31. Manually cooperate with the tower crane to use the lifting belt to lift the rope guide; S32, placing the cable guide tube on the gasket B of the platform A; S33, aligning the two corners of the cable guide bottom anchor plate with the marks of coordinate point 1 and coordinate point 2; Step S4 specifically includes: S41. Orient the upper end of the cable guide tube roughly toward the tower column cable saddle for rough positioning. S42. Install the axis centering tool C on the upper end of the cable guide tube and adjust the centering prism on the centering tool C to the center position. S43. The total station sets out the center position of the upper pipe opening according to the calculation, providing a spatial line of sight with the crosshairs as the control line; S44. Adjust the position of the upper tube opening up and down so that the crosshairs of the total station coincide with the centering prism of tooling C to complete the alignment. Step S5 specifically includes: S51. After the cable guide tube position meets the requirements, the tower crane lifting belt is not removed to maintain the position accuracy; S52. Install a "door"-shaped bracket D below the cable guide. The crossbeam of bracket D supports the cable guide. The lower portion of bracket D is welded to the bottom plate reinforcement. S53. Install a "door"-shaped bracket E on the upper portion of the cable guide tube, enclosing the cable guide tube. The crossbeam of bracket E presses down on the cable guide tube. The lower portion of bracket E is welded to the bottom plate reinforcement. S54. Use channel steel to make connecting beam F, clamp the cable guide and connect bracket D and bracket E; S55. Anchor the cable guide bottom anchor plate with a steel plate to press the template slot, press the four corners with steel bar pressure nails, and weld the pressure nails to the bottom plate steel bar.

2. The precise installation method of the cable-stayed bridge main beam cable guide according to claim 1 is characterized in that: Step S1 specifically includes: S11. Based on the design drawings, accurately lay out the perforation positions of the cable guide tube on the template; S12. Based on the position and size of the bottom anchor plate of the cable guide tube, a square slot is opened at the corresponding position of the template. The size of the slot is 5 cm larger than the bottom anchor plate, and there is 2.5 cm of movable space on each side of the slot.

3. The precise installation method of the cable-stayed bridge main beam cable guide according to claim 1 is characterized in that: Step S6 specifically includes: S61. Re-measure the elevation of the lower edge of the anchor pad at the bottom of the cable guide and coordinate points 1 and 2; S62, re-measure the coordinates of the axis center point of the upper pipe opening of the cable guide tube; S63. If there is an error between the re-measured data and the design data, continue to make adjustments. If the error with the design value is within the allowable range, remove the lifting belt and complete the positioning installation.

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