Arch rib overall lifting horizontal cable and tensioning method and tensioning control system of lifting cable
By alternating tensioning of horizontal and lifting cables under graded loads, combined with intelligent synchronous jacks and sensor systems, the problem of uneven alignment during the overall lifting of the arch rib was solved. This enabled the uniformity and stability control of the arch rib's alignment after it detaches from the low-level assembly support, and improved the efficiency of construction monitoring and cable force regulation.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- GUANGXI ROAD & BRIDGE ENG GRP CO LTD
- Filing Date
- 2025-12-04
- Publication Date
- 2026-04-10
AI Technical Summary
When constructing large-span steel-concrete arch bridges in confined terrains such as densely built-up urban areas, it is difficult to use conventional cable hoisting and inclined suspension methods. Furthermore, existing methods result in uneven arch rib alignment after detachment from the low-level assembly support, affecting the closure effect.
The method of tensioning the horizontal cables and lifting cables of the arch rib as a whole is adopted. The horizontal cables and lifting cables are tensioned alternately by graded loads. Combined with intelligent synchronous jacks and sensor systems, the cable force and displacement deviation are monitored and controlled in real time to ensure the uniformity and stability of the arch rib after it is separated from the support.
It achieved precise control of horizontal cable force and displacement at the closing end during the overall lifting of the arch rib, improved the displacement control accuracy and construction monitoring efficiency during the closing of the arch rib, and ensured the stability of the arch rib during the lifting process.
Smart Images
Figure CN121827232A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of bridge construction technology, specifically to a method and control system for tensioning the horizontal cable and lifting cable of the arch rib integral lifting structure. Background Technology
[0002] When constructing large-span steel-concrete composite arch bridges in densely built-up urban areas and other limited terrain conditions, the terrain restricts the arrangement of anchor structures such as main anchors and tie anchors, making it difficult to use the conventional cable hoisting and inclined cable-stayed method for the construction of the main arch ribs. The overall lifting method, due to its small construction area and relatively simple process, has become a reasonable alternative construction solution.
[0003] During the overall lifting of the arch rib, to ensure that the mid-section arch rib meets the control requirements and to maintain the stability of the structural system during the lifting process, temporary horizontal cables are usually tensioned near the closure joint of the lifted arch rib. The key challenges in the overall lifting of the arch rib lie in determining the appropriate tensioning procedure for the temporary horizontal cables and the lifting cables, and in effectively controlling the displacement of the mid-section arch rib joint during tensioning. Previous methods typically involved first tensioning the horizontal cables to the target tension on the low-level assembly support, and then tensioning the lifting cables to lift the arch rib off the support. However, because the resistance of the support distributes some of the horizontal cable force, after the arch rib is removed from the support, the cable force originally borne by the support is transferred to the arch rib, resulting in excessive inward displacement of the arch rib. This leads to an uneven arch rib profile after removal from the low-level assembly support, affecting the subsequent closure of the arch rib. Summary of the Invention
[0004] The present invention aims to solve at least one of the technical problems mentioned in the background art above, and provides a tensioning method for the horizontal cable and lifting cable of the overall arch rib lifting, which can achieve precise control of the horizontal cable force and the horizontal displacement of the closing end during the overall arch rib lifting construction process, so that the arch rib's alignment is as reasonable as possible after it is separated from the low-level assembly support and during the lifting process, ensuring the stability of the arch rib during the lifting process and improving the displacement control accuracy when the arch rib is closed.
[0005] To achieve the above objectives, the technical solution adopted by the present invention is as follows:
[0006] A method for tensioning the horizontal lifting cable and the lifting cable of an arch rib integral lifting structure includes the following steps:
[0007] S1. Measure the actual three-dimensional coordinates of the closure displacement control point when the arch rib is in the forming state on the low-position assembly support. Adjust the initial deviation between the actual three-dimensional coordinates and the design coordinates of the closure displacement control point to meet the control requirements, and start the tensioning operation.
[0008] S2, when the arch rib is located on the low-position assembly support, first, according to the specified load grade, alternately tension the horizontal cables and lifting cables to the corresponding grade cable force values. During the tensioning process, the cable force of the horizontal cables and lifting cables, as well as the actual three-dimensional coordinates of the closure joint displacement control point, are measured in real time. The deviation between the measured cable force of the horizontal cables and lifting cables and the design grade cable force value of the current load grade, as well as the station number deviation between the actual three-dimensional coordinates of the closure joint displacement control point and the design coordinates, are analyzed. When the cable force of the horizontal cables and lifting cables reaches the current load grade control value and the station number deviation of the closure joint displacement control point meets the control limit requirement of (0, 50 mm), the tensioning operation of the next load grade is carried out.
[0009] S3. When the tension of the horizontal cable reaches 90% of the design tension, the tension of the lifting cable is then increased to 100% of the design tension, and the arch rib is completely detached from the low-position assembly support.
[0010] S4. After the arch rib is detached from the low-position assembly support, the overall lifting of the arch rib begins. During the overall lifting of the arch rib, the tension of the horizontal cable is stretched to 95% of the design tension. During the tensioning process, the pile number deviation of the closing joint displacement control point is observed in real time and the pile number deviation is controlled within the control limit range of (0, 20mm). When the tension of the horizontal cable reaches 95% of the design tension, the tensioning is stopped.
[0011] S5, by tensioning the lifting cable, the arch rib is gradually lifted to the design elevation. During the lifting process, the pile number deviation of the closure joint displacement control point is monitored in real time, and the pile number deviation is controlled within the control limit range of (0, 20mm).
[0012] S6. After the arch rib is raised to the design elevation, the arch rib closing operation stage begins. Before the arch rib closing operation, the tension of the horizontal cable is increased from 95% to 100% of the design tension. During the tensioning process, the station number deviation of the closing joint displacement control point is observed in real time, and the station number deviation is controlled within the control limit range of [-10, 10mm].
[0013] S7, then the arch ribs are joined together to form an arch. After the arch ribs are joined together to form an arch, the tension of the horizontal cable and the lifting cable is gradually reduced to 0.
[0014] Furthermore, the horizontal cable and the lifting cable are tensioned using intelligent synchronous jacks.
[0015] Furthermore, when the initial deviation between the actual three-dimensional coordinates and the design coordinates of the closure displacement control point is less than 20mm, the control requirements are met.
[0016] Furthermore, in step S2, the horizontal cables and lifting cables are tensioned alternately with four load levels of 25%, 50%, 75%, and 90% to the corresponding graded cable force values.
[0017] Furthermore, in step S4, the changes in the tension of individual strands of the horizontal cable and the lifting cable, as well as the changes in the tension of the entire bundle of strands, are measured in real time during the tensioning process. The measured tension of an individual strand is compared with the average tension of an individual strand calculated from the tension of the entire bundle. When the relative deviation between the two is less than 10%, the entire bundle of cables is under uniform stress. If the relative deviation is greater than or equal to 10%, the changes in the tension of the horizontal cable and the lifting cable are closely monitored to avoid safety issues.
[0018] This invention further provides a tensioning control system for the tensioning method of the integral lifting horizontal cable and lifting cable of the arch rib. The tensioning control system includes a sensor module, a data transmission module, an analysis module, and a control module. The sensor module includes a displacement sensor and a force sensor. The displacement sensor is installed at the displacement control point of the arch rib closure joint to measure the actual three-dimensional coordinates of the closure joint displacement control point in real time. The force sensor is arranged on the horizontal cable and lifting cable to measure the cable force of the horizontal cable and lifting cable in real time. The data transmission module is used to remotely transmit the measured actual three-dimensional coordinates of the displacement control point and the cable force of the horizontal cable and lifting cable to the analysis module. The analysis module is used to compare the acquired actual three-dimensional coordinates of the displacement control point with a preset control limit to obtain the deviation of the displacement control point, and to compare the measured cable force of the horizontal cable and lifting cable with the corresponding design cable force to obtain the deviation of the cable force from the corresponding design cable force, and to determine the control command based on the deviation. The control module is used to control the corresponding intelligent synchronous jacks to perform operations according to the control command, thereby performing tensioning.
[0019] Furthermore, the displacement sensor includes a total station prism arranged on each chord displacement control point of the closure joint of the lifting section arch rib, and a measuring robot is used to perform real-time tracking and measurement of the three-dimensional coordinates of the displacement control points.
[0020] Furthermore, the tensioning control system also includes a visualization module, which is used to centrally and visually display the control indicators during the arch rib lifting process on a large screen. At the same time, the visualization module also includes a digital twin module, which contains a three-dimensional model of the arch rib lifting construction. The lifting position of the arch rib in the three-dimensional model is associated with the measurement data of the measuring robot, which can make the lifting position of the arch rib consistent with the actual lifting position of the arch rib in the project, thereby vividly displaying the lifting progress of the arch rib.
[0021] Furthermore, the force sensor includes a single-hole cable force sensor arranged on a single strand of the horizontal cable and the lifting cable, and a bundle cable force sensor arranged on the entire bundle of the horizontal cable and the lifting cable. The single-hole cable force sensor is used to measure the cable force change of a single strand during the tensioning process in real time, and the bundle cable force sensor is used to measure the cable force change of the entire bundle of steel strands during the tensioning process in real time.
[0022] By adopting the above technical solution, the present invention has the following beneficial effects:
[0023] The above-mentioned method for tensioning the horizontal and lifting cables of the arch rib is as follows: In the tensioning process, when the arch rib is on the low-level assembly support, the horizontal and lifting cables are tensioned alternately according to the specified load grades to the corresponding graded cable force values. After the horizontal cable force reaches 90% of the design cable force, the lifting cable force is then tensioned to 100% of the design cable force, completely detaching the arch rib from the low-level assembly support. After the arch rib is detached from the low-level assembly support, the horizontal cable force is tensioned to 95% of the design cable force, and then the arch rib is gradually lifted to the design elevation. Regarding control objectives, when the arch rib is on the low-level assembly support, the tensioning process uses whether the cable forces of the horizontal and lifting cables reach the graded cable force values and the station deviation as verification objectives; after the arch rib is detached from the low-level assembly support, the station deviation is used as the primary control objective. By using the overall lifting horizontal cable and the tensioning method of the lifting cable, precise control of the horizontal cable force and the horizontal displacement at the closing end can be achieved during the overall lifting construction of the arch rib. This ensures that the alignment of the arch rib is as reasonable as possible after it is separated from the low-level assembly support and during the lifting process. It also improves the efficiency of construction monitoring and cable force control during the arch rib lifting process, ensures the stability of the arch rib during the lifting process, and improves the displacement control accuracy when the arch rib is closed.
[0024] This invention also provides a tensioning control system for the horizontal and lifting cables of the arch rib lifting system. This system can track and measure the actual three-dimensional coordinates of the closure joint displacement control point and the cable forces of the horizontal and lifting cables in real time. It can compare the measured cable forces with the corresponding design cable forces to obtain the deviation between the cable forces and the design forces, and compare the actual three-dimensional coordinates of the displacement control point with preset control limits to obtain the deviation of the displacement control point. Based on the deviation, it determines the control commands for the intelligent synchronous jacks, thereby achieving automatic tensioning of the horizontal and lifting cables, and thus improving the efficiency of construction monitoring and cable force control during the arch rib lifting process. Attached Figure Description
[0025] Figure 1 This is a flowchart of a preferred embodiment of the tensioning method for the integral lifting horizontal cable and lifting cable of the arch rib according to the present invention.
[0026] Figure 2 A block diagram of the tension control system for the integral lifting horizontal cable and lifting cable of the arch rib, which is a preferred embodiment of the invention. Detailed Implementation
[0027] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.
[0028] It should be noted that when a component is described as "fixed to" another component, it can be directly on the other component or may have a component in between. When a component is considered "connected to" another component, it can be directly connected to the other component or may have a component in between. When a component is considered "set on" another component, it can be directly set on the other component or may have a component in between. The terms "vertical," "horizontal," "left," "right," and similar expressions used in this document are for illustrative purposes only.
[0029] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.
[0030] Please also see Figure 1 and Figure 2 A preferred embodiment of the present invention provides a tensioning method for an integral lifting horizontal cable and a lifting cable for an arch rib, comprising the following steps:
[0031] S1. Measure the actual three-dimensional coordinates of the closure displacement control point when the arch rib is in the forming state on the low-position assembly support. Adjust the initial deviation between the actual three-dimensional coordinates and the design coordinates of the closure displacement control point to meet the control requirements, and start the tensioning operation.
[0032] In this embodiment, the initial deviation between the actual three-dimensional coordinates and the design coordinates of the closure displacement control point is less than 20mm, which meets the control requirements.
[0033] S2, when the arch rib is located on the low-position assembly support, first, according to the specified load grade, alternately tension the horizontal cables and lifting cables to the corresponding grade cable force values. During the tensioning process, measure the cable force of the horizontal cables and lifting cables and the actual three-dimensional coordinates of the closure joint displacement control point in real time. Analyze the deviation between the measured cable force of the horizontal cables and lifting cables and the design grade cable force value of the current load grade, as well as the station number deviation between the actual three-dimensional coordinates of the closure joint displacement control point and the design coordinates. When the cable force of the horizontal cables and lifting cables reaches the current load grade control value and the station number deviation of the closure joint displacement control point meets the control limit requirement of (0, 50 mm), proceed with the tensioning operation of the next load grade.
[0034] In this embodiment, the horizontal cables and lifting cables are tensioned alternately to the corresponding graded cable force values at four load levels: 25%, 50%, 75%, and 90%. The method of alternately tensioning the horizontal cables and lifting cables to the corresponding graded cable force values according to the specified load levels is prior art and will not be described further here for brevity.
[0035] S3. After the horizontal cable tension reaches 90% of the design tension, the lifting cable tension is then increased to 100% of the design tension, and the arch rib is completely detached from the low-position assembly support.
[0036] S4. After the arch rib is detached from the low-position assembly support, the overall lifting of the arch rib begins. During the overall lifting of the arch rib, the tension of the horizontal cable is stretched to 95% of the design tension. During the tensioning process, the deviation of the station number at the closure control point is observed in real time and the station number deviation is controlled within the control limit range of (0, 20mm). Tensioning is stopped when the cable force reaches 95% of the design tension.
[0037] In step S4, the changes in the tension of individual strands of the horizontal cable and the lifting cable, as well as the changes in the tension of the entire bundle of strands, are measured in real time during the tensioning process. The measured tension of an individual strand is compared with the average tension of an individual strand calculated from the tension of the entire bundle. When the relative deviation between the two is less than 10%, the entire bundle of cables is considered to be under uniform stress. If the relative deviation is not less than 10%, the changes in the tension of the horizontal cable and the lifting cable should be closely monitored to avoid safety issues.
[0038] S5, by tensioning the lifting cable, the arch rib is gradually lifted to the design elevation. During the lifting process, the deviation of the station number of the closure joint displacement control point is monitored in real time, and the deviation of the station number is controlled within the control limit range of (0, 20mm).
[0039] S6. After the arch rib is raised to the design elevation, the arch rib closing operation stage begins. Before the arch rib closing operation, the tension of the horizontal cable is increased from 95% to 100% of the design tension. During the tensioning process, the station number deviation of the closing joint displacement control point is observed in real time, and the station number deviation is controlled within the control limit range of [-10, 10mm].
[0040] S7, then the arch ribs are joined together to form an arch. After the arch ribs are joined together to form an arch, the tension of the horizontal cable and the lifting cable is gradually reduced to 0.
[0041] This invention also provides a tensioning control system for the overall lifting horizontal cable and lifting cable of the arch rib, including a sensor module, a data transmission module, an analysis module, and a control module. The sensor module includes displacement sensors and force sensors. The displacement sensors are installed at the displacement control points of the arch rib closure joint to measure the actual three-dimensional coordinates of the closure joint displacement control points in real time. Specifically, the displacement sensors include total station prisms arranged on the displacement control points of each chord tube at the closure joint of the lifting section of the arch rib. A measuring robot is used to perform real-time tracking and measurement of the three-dimensional coordinates of the displacement control points. The measuring robot is a type of total station, differing from a conventional total station in that it can automatically search for and track prisms for measurement. Its structure is existing technology and will not be described in detail here for brevity.
[0042] The force sensors include single-hole cable force sensors arranged on individual steel strands of the horizontal and lifting cables, and bundled cable force sensors arranged on the entire bundle of cables of the horizontal and lifting cables. The single-hole cable force sensors are used to measure the cable force changes of individual steel strands of the horizontal and lifting cables in real time during the tensioning process; the bundled cable force sensors are used to measure the cable force changes of the entire bundle of steel strands of the horizontal and lifting cables in real time during the tensioning process.
[0043] The data transmission module is used to remotely transmit the actual three-dimensional coordinates of the measured displacement control points, as well as the cable forces of the horizontal and lifting cables, to the analysis module. In this embodiment, the data transmission module can adopt a 4G / 5G network transmission module, etc., which are existing technologies and will not be described in detail here for the sake of brevity.
[0044] The analysis module compares the actual three-dimensional coordinates of the acquired displacement control points with preset control limits to obtain the deviation of the displacement control points, and compares the measured cable forces of the horizontal and lifting cables with the corresponding design cable forces to obtain the deviation of the cable forces from the corresponding design cable forces, and determines the control commands based on the deviation. The analysis module also calculates the average value of the single cable force based on the cable force changes of the entire bundle of steel strands, thereby determining whether the tension of each steel strand is uniform. Specifically, the measured cable force of a single steel strand is compared with the average value of the single cable force calculated from the total cable force. When the relative deviation is less than 10%, the entire bundle of cables is considered to be under uniform tension; if the relative deviation is greater than or equal to 10%, close monitoring of the cable force changes of the horizontal and lifting cables is required to avoid safety issues. In this embodiment, the analysis module can use a processor based on existing technology, such as a computer.
[0045] The control module is used to control the corresponding intelligent synchronous jacks to perform operations according to control commands, thereby performing tensioning. In this embodiment, both the horizontal cable and the lifting cable are tensioned using intelligent synchronous jacks; the control module can use a controller based on existing technology, such as a PLC controller.
[0046] In this embodiment, the tensioning control system also includes a visualization module. This module centrally and visually displays the control indicators during the arch rib lifting process on a large screen. These control indicators include the jack's working status, the lifting cable force and its uniformity, lifting synchronicity (i.e., the elevation difference between the four arch rib displacement control points), the joint's longitudinal horizontal displacement, the lifting tower's deflection, the arch rib stress, and the horizontal cable force and its uniformity. Simultaneously, the visualization module also includes a digital twin module containing a three-dimensional model of the arch rib lifting construction. The lifting position of the arch rib in the three-dimensional model is linked to the measurement data from the measuring robot, ensuring that the arch rib's lifting position remains consistent with the actual lifting position in the project, thus vividly demonstrating the arch rib lifting progress.
[0047] The following specific embodiment illustrates the tensioning method of the integral lifting horizontal cable and lifting cable of the arch rib of the present invention.
[0048] The arch bridge is a 318-meter-span, mid-span steel-concrete composite arch bridge with a rise-to-span ratio of 1 / 4.48 and an arch axis coefficient of 1.5. Each arch rib adopts a variable-height four-tube truss section. The transverse center-to-center distance of the main arches on each span is 24.9m, the distance between the chords of the left and right main arches is 4.2m, the radial height of the arch crown section is 5m, the radial height of the arch foot section is 7m, and the rib width is 2.6m. The arch ribs are assembled using a low-position assembly support and then lifted and closed as a whole. The middle section of the arch rib weighs 1900t. Lifting gantry frames are erected on both banks of the steel-concrete composite arch rib, equipped with 8 LSD3500 lifting jacks, 4 hydraulic lifting pump stations, and 1 control system. To ensure the arch rib alignment and safety during the lifting process, one bundle of horizontal cables is arranged on each of the left and right sides, as well as the upper and lower steel pipe ribs, to limit deformation. A total of four bundles of 30×ф15.2mm steel strands are used as temporary tie rods, with 30 strands in each bundle, totaling 120 strands. The tension of a single horizontal cable bundle is 320t. Eight bundles of steel strands are arranged vertically on each side, with 20 strands in each bundle, totaling 160 strands. The tension of a single lifting cable bundle is 237.5t. After the middle section of the arch rib is lifted into place, it is joined with the arch ribs on both sides.
[0049] The specific steps for overall arch rib lifting using the tensioning method of the horizontal lifting cable and lifting cable of the present invention are as follows:
[0050] S1. Measure the actual three-dimensional coordinates of the closure joint displacement control point when the arch rib is in its formed state on the low-position assembly support. Adjust the initial deviation between the actual three-dimensional coordinates and the design coordinates of the closure joint displacement control point to meet the control requirements, and then begin the tensioning operation. In this embodiment, when the initial deviation between the three-dimensional coordinates and the design coordinates is less than 20mm, meeting the control requirements, the tensioning operation begins.
[0051] In this embodiment, there are four closure displacement control points, which are respectively arranged on the outside of the upper chord tube of the closure at both ends of the arch rib to be lifted section.
[0052] S2, when the arch rib is located on the low-level assembly support, the horizontal cables and lifting cables are tensioned alternately according to the specified load levels to the corresponding graded cable force values. In this embodiment, the horizontal cables and lifting cables are tensioned alternately to the corresponding graded cable force values at four load levels: 25%, 50%, 75%, and 90%. During the tensioning process, the cable forces of the horizontal cables and lifting cables, as well as the actual three-dimensional coordinates of the closure joint displacement control point, are measured in real time. The deviations between the measured cable forces of the horizontal cables and lifting cables and the design graded cable force values for the current load level, as well as the station number deviations between the actual three-dimensional coordinates of the closure joint displacement control point and the design coordinates, are analyzed. When the cable forces of the horizontal cables and lifting cables reach the current load level control value and the station number deviation of the closure joint displacement control point meets the control limit requirement of (0, 50mm), the tensioning operation for the next load level is carried out.
[0053] S3. After the horizontal cable tension reaches 90% of the design tension, the lifting cable tension is then increased to 100% of the design tension, causing the arch rib to completely detach from the low-level assembly support. In this embodiment, tensioning is stopped when the horizontal cable tension reaches 90% of the design tension (2880 kN), and the lifting cable tension is increased to 100% of the design tension (2375 kN) to completely detach the arch rib from the low-level assembly support.
[0054] S4. After the arch rib is detached from the low-position assembly support, the overall lifting of the arch rib begins. During the overall lifting of the arch rib, the tension of the horizontal cable is stretched to 95% of the design tension. During the tensioning process, the deviation of the station number at the closure control point is observed in real time and the station number deviation is controlled within the control limit range of (0, 20mm). Tensioning is stopped when the cable force reaches 95% of the design tension.
[0055] In this embodiment, the horizontal cable is tensioned from 90% of the cable force (2880kN) to 95% of the cable force (3040kN). During the tensioning process, the deviation of the control point of the closing joint displacement is monitored in real time, and the deviation is controlled within the range of (0, 20mm). The intelligent jack is controlled to perform tensioning according to the deviation of the chainage. Tensioning is stopped when the cable force reaches 95% of the design cable force (3040kN).
[0056] S5, by tensioning the lifting cable, the arch rib is gradually lifted to the design elevation. During the lifting process, the deviation of the station number of the closure joint displacement control point is monitored in real time, and the deviation of the station number is controlled within the control limit range of (0, 20mm).
[0057] In this embodiment, the arch rib is gradually lifted to the target height of 49.1m by tensioning the lifting cable. During the lifting process, the deviation of the station number of the closure joint displacement control point is observed in real time, and the deviation is controlled within the range of (0, 20mm).
[0058] S6. After the arch rib is raised to the design elevation, the arch rib closing operation stage begins. Before the arch rib closing operation, the tension of the horizontal cable is increased from 95% to 100% of the design tension. During the tensioning process, the station number deviation of the closing joint displacement control point is observed in real time, and the station number deviation is controlled within the control limit range of [-10, 10mm].
[0059] In this embodiment, the horizontal cable is tensioned from 95% of the cable force (3040kN) to 100% of the design cable force (3200kN). During the tensioning process, the deviation of the station number of the closure joint displacement control point is observed in real time, and the deviation is controlled within the range of [-10, 10mm].
[0060] S7. Subsequently, the arch ribs are joined to form an arch. After the arch ribs are joined to form an arch, the tension of the horizontal cables and lifting cables is gradually and alternately reduced to 0. This step is existing technology and will not be described in detail here for brevity.
[0061] The above-mentioned method for tensioning the horizontal and lifting cables of the arch rib is as follows: In the tensioning process, when the arch rib is on the low-level assembly support, the horizontal and lifting cables are tensioned alternately according to the specified load grades to the corresponding graded cable force values. After the horizontal cable force reaches 90% of the design cable force, the lifting cable force is then tensioned to 100% of the design cable force, completely detaching the arch rib from the low-level assembly support. After the arch rib is detached from the low-level assembly support, the horizontal cable force is tensioned to 95% of the design cable force, and then the arch rib is gradually lifted to the design elevation. Regarding control objectives, when the arch rib is on the low-level assembly support, the tensioning process uses whether the cable forces of the horizontal and lifting cables reach the graded cable force values and the station deviation as verification objectives; after the arch rib is detached from the low-level assembly support, the station deviation is used as the primary control objective. By using the overall lifting horizontal cable and the tensioning method of the lifting cable, precise control of the horizontal cable force and the horizontal displacement at the closing end can be achieved during the overall lifting construction of the arch rib. This ensures that the alignment of the arch rib is as reasonable as possible after it is separated from the low-level assembly support and during the lifting process. It also improves the efficiency of construction monitoring and cable force control during the arch rib lifting process, ensures the stability of the arch rib during the lifting process, and improves the displacement control accuracy when the arch rib is closed.
[0062] This invention also provides a tensioning control system for the horizontal and lifting cables of the arch rib lifting system. This system can track and measure the actual three-dimensional coordinates of the closure joint displacement control point and the cable forces of the horizontal and lifting cables in real time. It can compare the measured cable forces with the corresponding design cable forces to obtain the deviation between the cable forces and the design forces, and compare the actual three-dimensional coordinates of the displacement control point with preset control limits to obtain the deviation of the displacement control point. Based on the deviation, it determines the control commands for the intelligent synchronous jacks, thereby achieving automatic tensioning of the horizontal and lifting cables, and thus improving the efficiency of construction monitoring and cable force control during the arch rib lifting process.
[0063] The above description is a detailed description of the preferred embodiments of the present invention. However, the embodiments are not intended to limit the scope of the patent application of the present invention. All equivalent changes or modifications made under the technical spirit of the present invention should fall within the patent scope covered by the present invention.
Claims
1. A method for tensioning the horizontal lifting cable and the lifting cable of an arch rib as a whole, characterized in that, Includes the following steps: S1. Measure the actual three-dimensional coordinates of the closure displacement control point when the arch rib is in the forming state on the low-position assembly support. Adjust the initial deviation between the actual three-dimensional coordinates and the design coordinates of the closure displacement control point to meet the control requirements, and start the tensioning operation. S2, when the arch rib is located on the low-position assembly support, first, according to the specified load grade, alternately tension the horizontal cables and lifting cables to the corresponding grade cable force values. During the tensioning process, the cable force of the horizontal cables and lifting cables, as well as the actual three-dimensional coordinates of the closure joint displacement control point, are measured in real time. The deviation between the measured cable force of the horizontal cables and lifting cables and the design grade cable force value of the current load grade, as well as the station number deviation between the actual three-dimensional coordinates of the closure joint displacement control point and the design coordinates, are analyzed. When the cable force of the horizontal cables and lifting cables reaches the current load grade control value and the station number deviation of the closure joint displacement control point meets the control limit requirement of (0, 50mm), the tensioning operation of the next load grade is carried out. S3. When the tension of the horizontal cable reaches 90% of the design tension, the tension of the lifting cable is then increased to 100% of the design tension, and the arch rib is completely detached from the low-position assembly support. S4. After the arch rib is detached from the low-position assembly support, the overall lifting of the arch rib begins. During the overall lifting of the arch rib, the tension of the horizontal cable is stretched to 95% of the design tension. During the tensioning process, the pile number deviation of the closing joint displacement control point is observed in real time and the pile number deviation is controlled within the control limit range of (0, 20mm). When the tension of the horizontal cable reaches 95% of the design tension, the tensioning is stopped. S5, by tensioning the lifting cable, the arch rib is gradually lifted to the design elevation. During the lifting process, the pile number deviation of the closure joint displacement control point is monitored in real time, and the pile number deviation is controlled within the control limit range of (0, 20mm). S6. After the arch rib is raised to the design elevation, the arch rib closing operation stage begins. Before the arch rib closing operation, the tension of the horizontal cable is increased from 95% to 100% of the design tension. During the tensioning process, the station number deviation of the closing joint displacement control point is observed in real time, and the station number deviation is controlled within the control limit range of [-10, 10mm]. S7, then the arch ribs are joined together to form an arch. After the arch ribs are joined together to form an arch, the tension of the horizontal cable and the lifting cable is gradually reduced to 0.
2. The tensioning method for the integral lifting horizontal cable and lifting cable of the arch rib as described in claim 1, characterized in that, The horizontal cable and the lifting cable are tensioned using intelligent synchronous jacks.
3. The tensioning method for the integral lifting horizontal cable and lifting cable of the arch rib as described in claim 1, characterized in that, In step S1, if the initial deviation between the actual three-dimensional coordinates and the design coordinates of the closure displacement control point is less than 20mm, the control requirements are met.
4. The tensioning method for the integral lifting horizontal cable and lifting cable of the arch rib as described in claim 1, characterized in that, In step S2, the horizontal cables and lifting cables are tensioned alternately with four load levels of 25%, 50%, 75%, and 90% to the corresponding graded cable force values.
5. The tensioning method for the integral lifting horizontal cable and lifting cable of the arch rib as described in claim 1, characterized in that, In step S4, the changes in the tension of individual strands of the horizontal cable and the lifting cable, as well as the changes in the tension of the entire bundle of strands, are measured in real time during the tensioning process. The measured tension of an individual strand is compared with the average tension of an individual strand calculated from the tension of the entire bundle. When the relative deviation between the two is less than 10%, the entire bundle of cables is under uniform stress. If the relative deviation is greater than or equal to 10%, the changes in the tension of the horizontal cable and the lifting cable should be closely monitored to avoid safety issues.
6. The tension control system used in the tensioning method for the integral lifting horizontal cable and lifting cable of the arch rib as described in claim 2, characterized in that, The tensioning control system includes a sensor module, a data transmission module, an analysis module, and a control module. The sensor module includes a displacement sensor and a force sensor. The displacement sensor is installed at the displacement control point of the arch rib closure joint to measure the actual three-dimensional coordinates of the closure joint displacement control point in real time. The force sensor is arranged on the horizontal cable and the lifting cable to measure the cable force of the horizontal cable and the lifting cable in real time. The data transmission module is used to remotely transmit the actual three-dimensional coordinates of the measured displacement control point, as well as the cable forces of the horizontal cable and the lifting cable, to the analysis module. The analysis module is used to compare the actual three-dimensional coordinates of the obtained displacement control point with the preset control limit to obtain the deviation of the displacement control point, and to compare the measured cable force of the horizontal cable and the lifting cable with the corresponding design cable force to obtain the deviation of the cable force from the corresponding design cable force, and to determine the control command based on the deviation. The control module is used to control the corresponding intelligent synchronous jacks to perform operations according to the control instructions, thereby performing tensioning.
7. The tensioning control system as described in claim 6, characterized in that, The displacement sensor includes a total station prism arranged on each chord displacement control point at the closure joint of the lifting section arch rib, and a measuring robot is used to perform real-time tracking and measurement of the three-dimensional coordinates of the displacement control points.
8. The tensioning control system as described in claim 6, characterized in that, The tensioning control system also includes a visualization module, which is used to centrally and visually display the control indicators during the arch rib lifting process on a large screen. Simultaneously, the visualization module also includes a digital twin module, which contains a three-dimensional model of the arch rib lifting construction. The lifting position of the arch rib in the three-dimensional model is linked to the measurement data of the measuring robot, ensuring that the lifting position of the arch rib is consistent with the actual lifting position in the project, thus vividly demonstrating the lifting progress of the arch rib.
9. The tensioning control system as described in claim 6, characterized in that, The force sensor includes a single-hole cable force sensor arranged on a single steel strand of the horizontal cable and the lifting cable, and a bundle cable force sensor arranged on the entire bundle of cables of the horizontal cable and the lifting cable. The single-hole cable force sensor is used to measure the cable force change of a single steel strand during the tensioning process in real time, and the bundle cable force sensor is used to measure the cable force change of the entire bundle of steel strands during the tensioning process in real time.