Asymmetric cable force tensioning rapid fixing device and using method

Abstract

The invention discloses an asymmetric cable force tensioning rapid fixing device and a using method, and relates to the technical field of bridge cable tension, and the using method comprises the steps of tensioning construction preparation, cable installation construction, cable tensioning construction, cable asymmetric tensioning construction and inspection and adjustment after cable tensioning is completed. Aiming at the tensioning construction of the inhaul cable, the tensioning device is designed into a plurality of detachable and assembled modules, when the tensioning device is installed in a cable bent tower, the modular design facilitates transportation and in-place in a narrow and complex space, the problem of space limitation can be effectively solved, the installation process is more flexible, the installation difficulty caused by the narrow space is reduced, and the construction efficiency is improved. And meanwhile, the position and the angle of the inhaul cable can be more accurately adapted when the device is fixedly connected with the inhaul cable, the accuracy and the stability of connection are ensured, the situation of uneven stress caused by improper connection is reduced, the construction efficiency is improved, the installation and preparation time is shortened, and the construction difficulty is reduced.

Description

Technical Field

[0001] The invention relates to the technical field of bridge cable tensioning technology, and in particular to an asymmetric cable tensioning quick fixing device and a use method thereof. Background Art

[0002] During the cantilever construction stage of a cable-stayed bridge, the main beam of the bridge is extended section by section. Due to the uneven load distribution in each construction stage, asymmetric cable tensioning can be used to balance the asymmetric load and prevent excessive deformation of the main beam and redistribution of internal force. At the same time, the asymmetric cable tensioning construction method can also enable the bridge to cope with special load conditions. For example, when designing the bridge, vehicles concentrate on driving on one side of the bridge, eccentric wind loads, etc. Through asymmetric cable tensioning, the internal force and line shape of the structure can be adjusted during the operation stage of the bridge to improve the stability of the bridge.

[0003] In the prior art, due to the structural design characteristics of the cable-stayed bridge itself, the cables are arranged obliquely with the main beam and the cable tower. The connection angles of the cables with the main beam and the cable tower are determined according to the structural design. In order to enable the tension applied by the jack during the cable tensioning process to be more effectively transmitted along the cable direction, reduce the lateral force component, and avoid excessive lateral force during the tensioning process, which may cause local wear and fatigue of the cables and affect the service life and safety performance of the cables, the tensioning device needs to be accurately installed at a set position inside the cable tower.

[0004] However, in the prior art, when the cable force is asymmetrically tensioned, the design of the cable tower mainly considers its structural stress and appearance factors, and the internal space is designed only to accommodate necessary structural components and necessary construction work space. However, during the on-site construction process, due to the large volume of the reaction support and the tension structure, in the actual operation process, it is necessary to consider both the accuracy and stability of the installation. It is difficult to quickly install them in place in a small space to complete the tensioning operation, resulting in the inability to quickly install and fix the cables, affecting the entire construction process and subsequent construction progress. Because the cables are the main load-bearing components in structures such as cable-stayed bridges, their function is to transfer the load of the main beam to the cable tower. Therefore, if the cables cannot be quickly tensioned and fixed, the force flow transmission path of the entire structure will be incomplete, affecting the overall stability of the structure, especially when encountering accidental loads such as wind loads, the ability of the structure to resist external forces will be weakened, increasing the possibility of structural instability. Summary of the invention

[0005] The purpose of the present invention is to provide an asymmetric cable tensioning quick fixing device and a method of use, so as to solve the problem raised by the above-mentioned background technology that during the on-site construction operation, due to the large volume of the reaction force support and the tension structure, in the actual operation process, it is necessary to consider both the installation accuracy and the installation stability. It is difficult to quickly install them in a small space to complete the tensioning operation, resulting in the inability to quickly install and fix the cables, affecting the entire construction process and subsequent construction progress. Because the cables are the main load-bearing components in structures such as cable-stayed bridges, their function is to transfer the load of the main beam to the cable tower, so the cables cannot be quickly tensioned and fixed, which will cause the force flow transmission path of the entire structure to be incomplete, affecting the overall stability of the structure.

[0006] To achieve the above-mentioned purpose, the present invention provides the following technical solutions: an asymmetric cable tensioning quick fixing device, comprising a tensioning device, the tensioning device comprising a supporting mechanism, a tensioning mechanism is installed on the upper part of the supporting mechanism, an auxiliary mechanism is installed on the upper part of the tensioning mechanism, the supporting mechanism is used to fix the entire installation at the tensioning position of the cable tower, an anchor plate is fixedly connected to the surface of the tensioning mechanism, an adapted clip is arranged inside the anchor plate, the anchor plate and the clip are used to fix the tensioning end of the cable, the tensioning mechanism is used to tension the cable, and the auxiliary mechanism is used for the tensioning mechanism to monitor the uniformity of the tension when the cable is tensioned;

[0007] The top of described supporting ram is hinged on the base, and the top of described supporting ram is hinged on the base, and the supporting ram of described supporting ram is hinged on the base, and the supporting ram of described supporting ram is hinged on the base, and the supporting ram of described supporting ram is hinged on the base.

[0008] Preferably, the mounting base is installed with a No. 1 connecting plate, the upper part of the No. 1 connecting plate is fixedly connected to a supporting jack, the upper part of the supporting jack is fixedly connected to a No. 1 supporting bracket, the side of the mounting sleeve is fixedly connected to a supporting plate, and the No. 1 supporting bracket is fitted with the bottom of the support plate.

[0009] Preferably, a fixing bolt is threadedly connected to the side surface of the positioning frame, and the fixing bolt passes through the positioning frame and is threadedly connected to the positioning base.

[0010] Preferably, the auxiliary mechanism includes an installation limit plate and an installation plug plate, the installation limit plate is fixedly connected to the upper part of the No. 2 connecting plate, the installation plug plate is slidably plugged with the installation limit plate, and the upper part of the installation plug plate is fixedly connected to a connecting frame, the side of the connecting frame is fixedly connected to a No. 1 fixing plate, the bottom of the No. 1 fixing plate is fixedly connected to a pressure sensor, the bottom of the pressure sensor is fixedly connected to a No. 2 fixing plate, the bottom of the No. 2 fixing plate is fixedly connected to a telescopic rod, the bottom of the telescopic rod is fixedly connected to a No. 3 fixing plate, a spring is arranged on the surface of the telescopic rod, one end of the spring is fixedly connected to the No. 2 fixing plate, and the other end of the spring is fixedly connected to the No. 3 fixing plate, and the No. 3 fixing plate is in contact with the surface of the tensioning plate.

[0011] A method for using asymmetric cable tensioning and quick fixing, comprising the following steps:

[0012] S1. Preparation for tensioning construction: prepare measuring tools and measure the length of the cable, prepare and debug the tensioning device, inspect the anchorage area of ​​the cable tower and the main beam, and determine the construction control parameters. The tensioning device itself can be disassembled into several components, and the several components can be gradually installed inside the cable tower according to the design steps;

[0013] S2. Cable installation and construction: First, the cables are hoisted and threaded, and then the cable positions are adjusted;

[0014] S3, cable tensioning construction: firstly, the cables are tensioned initially, then tensioned in stages, and finally tensioned in the final stage;

[0015] S4, asymmetric cable tensioning construction: determine the tensioning sequence of the cables according to the design and construction control parameters, adjust the asymmetric cable force during the asymmetric tensioning process, and monitor, feedback and adjust the tensioning process at the same time;

[0016] S5. Inspection and adjustment after cable tensioning: re-measure the cable force, check the elongation of the cable, check the main beam line shape and stress, and inspect and protect the anchorage area.

[0017] Preferably, in step S1, the steps of preparing a measuring tool and measuring the length of the cable, preparing a tensioning device and debugging the tensioning device, inspecting the anchorage area of ​​the cable tower and the main beam, and determining the construction control parameters include the following steps:

[0018] S11. Select a total station with a measurement accuracy of ±1 mm as a measuring instrument, and measure the length of the cable using the total station;

[0019] S12. According to the design cable force of the cable, select an appropriate tensioning device. The rated tension of the tensioning device should be greater than 1.3 times the maximum design cable force of the cable. The tensioning device should be debugged at the construction site;

[0020] S13. Check the concrete strength of the anchorage points of the cables on the towers and main beams, the size, flatness and corrosion resistance of the anchorage steel components, and clean up the debris around the anchorage area;

[0021] S14. Use bridge structure analysis software to build a finite element model of the bridge to analyze the stress state of the cables and the linear changes of the main beams at each construction stage. Based on the analysis results of the finite element model and combined with the design requirements, calculate the theoretical cable force values ​​of the cables to be tensioned. At the same time, correct the theoretical cable force values ​​according to the shrinkage, creep, and temperature changes of the concrete.

[0022] Preferably, in step S2, firstly lifting and threading the cable, and then adjusting the position of the cable comprises the following steps:

[0023] S21. Selecting suitable lifting equipment according to the weight and length of the cable, wherein the lifting equipment is at least one of a crane and a tower crane;

[0024] S22, lifting one end of the cable to the top of the cable tower anchoring area by a lifting device, and then slowly lowering it, so that the anchor head of the cable is inserted into the anchor hole on the cable tower for temporary fixation, lifting the other end of the cable to the top of the main beam anchoring area, and then slowly lowering it, and inserting the anchor head into the anchor hole of the main beam to complete the cable threading;

[0025] S23. Use a hand winch or a small jack to move the cable in the anchoring area, adjust the position of the cable in the anchoring area, monitor with a measuring tool, align the cable with the center line of the anchor hole, and ensure that the deviation is no more than ±3mm.

[0026] Preferably, in step S3, the process of firstly performing an initial tensioning on the cable, then performing a graded tensioning on the cable, and finally performing a final tensioning on the cable comprises the following steps:

[0027] S31. Use a tensioning device to fix and tension the cable. When the cable force of the cable reaches 30% of the tensioning design value, suspend tensioning and inspect the cable, anchoring area and tensioning device.

[0028] S32, dividing the tensioning process of the cable into multiple levels, the cable force increment of each level of tensioning is 15%-20% of the design cable force, and suspending the tensioning for 6-15 minutes after each level of tensioning is completed. When the cable force reaches 80% of the design cable force, suspending the tensioning and inspecting the cable, anchoring area and tensioning device;

[0029] S33, continue to tension the cable, and when the cable force reaches 95% of the design cable force, adjust the cable force increment to 1%-2% of the design cable force, and stop tensioning when the cable force reaches the design cable force.

[0030] Preferably, in step S4, determining the tensioning sequence of the cables according to the design and construction control parameters, adjusting the asymmetric cable force during the asymmetric tensioning process, and monitoring, feeding back and adjusting the tensioning process at the same time include the following steps:

[0031] S41. According to the length of the cable and the position on the main beam surface, the cable is gradually tensioned in the order of short first and long later, and inside first and outside later;

[0032] S42. When tensioning the subsequent cables, the cable force is adjusted according to the force distribution principle of asymmetric tensioning;

[0033] S43. During the cable tensioning process, monitor the vertical displacement, lateral displacement and torsion angle of the main beam, the change in the tension of the tensioned cables and the stress in the anchorage area of ​​the main beam.

[0034] Preferably, in step S5, the re-measurement of the cable force, the verification of the elongation of the cable, the inspection of the main beam linear shape and stress, and the inspection and protection of the anchorage area include the following steps:

[0035] S51. Establish measurement points at the middle and anchorage ends of the cable, use force measuring equipment to re-measure the cable force, compare the re-measured cable force with the designed cable force, and the deviation is no more than ±5% to be qualified;

[0036] S52. Calculate the theoretical elongation of the cable according to its actual cable force, elastic modulus and length, and compare it with the actual elongation measured during the tensioning process. The deviation is not more than ±6%, which is considered acceptable.

[0037] S53. Use a total station and a level to measure the elevation, mid-span deflection, and cantilever end displacement of the main beam;

[0038] S54. Strain gauges are arranged at the mid-span, support points and cable anchorage areas of the main beam to detect the stress of the main beam. The measured stress is compared with the design stress. The deviation is not more than ±5% and is considered acceptable.

[0039] S55. Check the anchor heads of the cables at the anchorage areas on the towers and main beams, the concrete condition of the anchorage areas, and the anti-corrosion coatings at the anchorage areas. At the same time, set up permanent protective devices around the anchorage areas. The protective devices are either protective covers or anti-corrosion coatings.

[0040] Compared with the prior art, the present invention has the following beneficial effects:

[0041] 1. In this method, the tensioning device is designed into multiple modules that can be disassembled and assembled. When installed inside the cable tower, the modular design is convenient for transportation and placement in a narrow and complex space, which can effectively solve the problem of space limitation, make the installation process more flexible, and reduce the installation difficulties caused by the small space. At the same time, when fixedly connected with the cable, it can more accurately adapt to the position and angle of the cable, ensure the accuracy and stability of the connection, reduce the uneven force caused by improper connection, improve construction efficiency, shorten the installation and preparation time, and reduce the difficulty of construction. In addition, the modules are individually calibrated and adjusted, which is conducive to improving the overall accuracy of the tensioning device, ensuring the accuracy of the cable tensioning, and better achieving the goal of asymmetric cable tensioning on the load balance and linear control of the cantilever end of the main beam, thereby ensuring the construction quality and structural safety.

[0042] 2. In this method, the fixing bolts of the pre-buried tensioning device of the installation base and the cable tower are used for fixing connection. According to the height of several installation sleeves after the installation base is fixed, the threaded support rod is rotated, and the threaded support rod is extended and retracted along the threaded sleeve to adjust the height of the installation sleeve so that the height of the installation sleeve is accurate, thereby ensuring the accurate installation position of the tensioning mechanism. The tensioning jack can also be removed from between the tensioning plate and the second connecting plate, and then each component is gradually installed. By splitting and installing the tensioning mechanism, the overall weight and volume during the installation process are reduced, which is convenient for fast and accurate installation of the tensioning mechanism, thereby improving the speed of tensioning construction of the cable;

[0043] 3. In this method, when the tensioning jack is lifting the tensioning plate, if the lifting pressure is large, the No. 1 support bracket is lifted by the support jack to support the bottom of the support plate, thereby providing a stable supporting force for the tensioning jack. At the same time, the force-bearing area of ​​the supporting force at the bottom of the tensioning device is increased by the No. 1 connecting plate, so as to avoid the pressure being concentrated in the anchoring area during the tensioning process, and to prevent the concrete from cracking and anchoring failure due to excessive pressure in the anchoring area. This ensures that the cable is anchored reliably, maintains the overall stability and safety of the structure, and extends the service life of the structure.

[0044] 4. In this method, during the tensioning process of the cable, the tensioning plate will move upward. At this time, the tensioning plate will drive the No. 3 fixed plate to push the telescopic rod and the spring to produce deformation. At this time, the No. 2 fixed plate will transmit the pressure generated by the deformation to the pressure sensor. The stress conditions at multiple positions on the surface of the tensioning plate are monitored by multiple pressure sensors arranged on the upper part of the tensioning plate. When the force on one side of the tensioning plate surface is too large, it indicates that the tensioning force of the tensioning mechanism on the cable is biased to one side, and the tension on the other side needs to be increased, or the tension on one side needs to be reduced, so that the cable is evenly stressed during the tensioning process. Ensuring that the cable is evenly stressed during the tensioning process can make the cable give full play to its bearing capacity, effectively transfer the load, and avoid local stress concentration, thereby ensuring the safety and stability of the structure, extending the service life of the cable, and improving the durability of the entire structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Figure 1 It is a three-dimensional schematic diagram of a tensioning device in an asymmetric cable tensioning quick fixing device of the present invention;

[0046] Figure 2 It is a side structural schematic diagram of a tensioning device in an asymmetric cable tensioning quick fixing device of the present invention;

[0047] Figure 3 It is a schematic diagram of the disassembly structure of the installation sleeve and the installation plug rod of the tensioning device in the asymmetric cable tensioning quick fixing device of the present invention;

[0048] Figure 4 It is a schematic diagram of the three-dimensional structure of a tensioning mechanism of a tensioning device in an asymmetric cable tensioning quick fixing device of the present invention;

[0049] Figure 5 It is a schematic diagram of a three-dimensional structure of a tensioning plate section of a tensioning device in an asymmetric cable tensioning quick fixing device of the present invention;

[0050] Figure 6 It is a side structural schematic diagram of an auxiliary mechanism of a tensioning device in an asymmetric cable tensioning quick fixing device of the present invention;

[0051] Figure 7 It is a schematic diagram of the installation and use of a tensioning device in an asymmetric cable tensioning quick fixing device of the present invention;

[0052] Figure 8 The present invention is a flow chart of a method for using asymmetric cable tensioning and rapid fixation.

[0053] In the figure: 1. Support mechanism; 11. Mounting base; 12. Threaded sleeve; 13. Threaded support rod; 14. Support plate; 15. Mounting sleeve; 16. No. 1 connecting plate; 17. Support jack; 18. No. 1 supporting bracket; 2. Tensioning mechanism; 21. Mounting plug rod; 22. No. 2 connecting plate; 23. Positioning frame; 24. Positioning base; 25. Tensioning jack; 26. No. 2 supporting bracket; 27. Tensioning plate; 28. Mounting bolt; 29. ​​Guide plate; 210. Tensioning limit plate; 3. Auxiliary mechanism; 31. Mounting limit plate; 32. Mounting plug plate; 33. Connecting frame; 34. No. 1 fixing plate; 35. Pressure sensor; 36. No. 2 fixing plate; 37. Telescopic rod; 38. No. 3 fixing plate; 39. Spring; 4. Anchor plate; 5. Clip. DETAILED DESCRIPTION

[0054] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the implementation regulations described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0055] Embodiment 1: According to Figure 1-Figure 7 As shown, in step S1, the tensioning device comprises a support mechanism 1, a tensioning mechanism 2 is installed on the upper part of the support mechanism 1, an auxiliary mechanism 3 is installed on the upper part of the tensioning mechanism 2, the support mechanism 1 is used to fix the entire installation at the tensioning position of the cable tower, an anchor plate 4 is fixedly connected to the surface of the tensioning mechanism 2, an adapted clip 5 is arranged inside the anchor plate 4, the anchor plate 4 and the clip 5 are used to fix the tensioning end of the cable, the tensioning mechanism 2 is used to tension the cable, and the auxiliary mechanism 3 is used for the tensioning mechanism 2 to monitor the uniformity of the tension when the cable is tensioned;

[0056] The support mechanism 1 includes a mounting base 11, a threaded sleeve 12 is fixedly connected to the upper part of the mounting base 11, a threaded support rod 13 is threadedly connected to the inner part of the threaded sleeve 12, and a mounting sleeve 15 is fixedly connected to the upper part of the threaded support rod 13. The tensioning mechanism 2 includes a mounting plug rod 21, a mounting bolt 28 and a tensioning plate 27. The bottom of the mounting plug rod 21 is plugged into the mounting sleeve 15, and the top of the mounting plug rod 21 is fixedly connected to a second connecting plate 22, and the upper part of the second connecting plate 22 is fixedly connected to a positioning frame 23, and a positioning base 24 is plugged into the positioning frame 23. The bottom of the positioning base 24 is fitted with the second connecting plate 22, and the top of the positioning base 24 is fixedly connected to a tensioning jack 25, and the top of the tensioning jack 25 is fixedly connected to a second supporting bracket 26, and the upper part of the second supporting bracket 26 is threadedly connected to the It is connected with mounting bolts 28, and the tensioning plate 27 is fixedly connected to the No. 2 supporting bracket 26 through the mounting bolts 28. The upper part of the No. 2 connecting plate 22 is fixedly connected with a guide plate 29, and a tensioning limit plate 210 is slidably inserted inside the guide plate 29. The tensioning limit plate 210 is fixedly connected to the bottom of the tensioning plate 27, and the side of the tensioning limit plate 210 is fixedly connected to the anchor plate 4. The mounting base 11 is installed with a No. 1 connecting plate 16, and the upper part of the No. 1 connecting plate 16 is fixedly connected with a supporting jack 17, and the upper part of the supporting jack 17 is fixedly connected with a No. 1 supporting bracket 18. The side of the mounting sleeve 15 is fixedly connected with the supporting plate 14, and the No. 1 supporting bracket 18 is fitted with the bottom of the supporting plate 14. The side of the positioning frame 23 is threadedly connected with a fixing bolt, and the fixing bolt passes through the positioning frame 23 and is threadedly connected to the positioning base 24.

[0057] In this embodiment, the mounting base 11 is fixedly connected with the fixing bolts of the tensioning device embedded in the cable tower. According to the height of several mounting sleeves 15 after the mounting base 11 is fixed, the threaded support rod 13 is rotated, and the threaded support rod 13 is extended and retracted along the threaded sleeve 12 to adjust the height of the mounting sleeve 15, so that the height of the mounting sleeve 15 is accurate, thereby ensuring the accurate installation position of the tensioning mechanism 2, so that the tensioning mechanism 2 can accurately tension the cable, and the installation plug rod 21 is used to be plugged into the installation sleeve 15, so that the tensioning mechanism 2 can be quickly installed on the support machine At the upper part of the structure 1, the tensioning end of the cable is passed through the second connecting plate 22 and the bottom of the anchor plate 4, and then passed through the center of the clamp 5. Then the tensioning jack 25 is lifted up, driving the tensioning plate 27 and the tensioning limit plate 210 to pull the anchor plate 4. At this time, the clamp 5 is tightened along the inside of the anchor plate 4 to fix the cable, and the tensioning operation of the cable is completed following the movement of the anchor plate 4. During the movement of the anchor plate 4, the tensioning limit plate 210 slides along the guide plate 29 to limit the movement of the anchor plate 4, thereby improving the stability of the anchor plate 4 during movement, and ensuring that the tensioning force of the cable is tensioned along the set angle.

[0058] At the same time, when the tensioning device is installed in a particularly narrow space, the tensioning jack 25 can be removed from between the tensioning plate 27 and the second connecting plate 22, and the tensioning plate 27 can be removed from the upper part of the second connecting plate 22. During installation, the positioning base 24 is limited by the positioning frame 23, and then the tensioning jack 25 is quickly installed on the surface of the second connecting plate 22 using the fixing bolts. Subsequently, the tensioning plate 27 is quickly positioned and installed by plugging the tensioning limiting plate 210 with the guide plate 29, and is threadedly connected to the second supporting bracket 26 by the mounting bolts 28, so as to facilitate the rapid fixing of the tensioning plate 27. By splitting and installing the tensioning mechanism 2, the overall weight and volume during the installation process are reduced, so that the tensioning mechanism 2 can be quickly and accurately installed, thereby improving the speed of tensioning the cable.

[0059] When the tensioning jack 25 is lifting the tensioning plate 27, if the lifting pressure is relatively large, the No. 1 support bracket 18 is lifted by the support jack 17 to support the bottom of the support plate 14, thereby providing a stable supporting force for the tensioning jack 25. At the same time, the No. 1 connecting plate 16 is used to increase the force-bearing area of ​​the supporting force at the bottom of the tensioning device to avoid excessive concentration of pressure at the tensioning position of the cable tower, thereby damaging the cable tower, and avoiding deformation of the threads between the threaded support rod 13 and the threaded sleeve 12, thereby affecting the next use.

[0060] Embodiment 2: According to Figure 1-Figure 7 As shown, the auxiliary mechanism 3 includes an installation limit plate 31 and an installation plug plate 32, the installation limit plate 31 is fixedly connected to the upper part of the No. 2 connecting plate 22, the installation plug plate 32 is slidably plugged with the installation limit plate 31, and the upper part of the installation plug plate 32 is fixedly connected to a connecting frame 33, and the side of the connecting frame 33 is fixedly connected to a No. 1 fixing plate 34, the bottom of the No. 1 fixing plate 34 is fixedly connected to a pressure sensor 35, the bottom of the pressure sensor 35 is fixedly connected to a No. 2 fixing plate 36, the bottom of the No. 2 fixing plate 36 is fixedly connected to a telescopic rod 37, the bottom of the telescopic rod 37 is fixedly connected to a No. 3 fixing plate 38, a spring 39 is arranged on the surface of the telescopic rod 37, one end of the spring 39 is fixedly connected to the No. 2 fixing plate 36, and the other end of the spring 39 is fixedly connected to the No. 3 fixing plate 38, and the No. 3 fixing plate 38 is in contact with the surface of the tensioning plate 27.

[0061] In this embodiment, during the process of tensioning the cable, the tensioning plate 27 will move upward. At this time, the tensioning plate 27 will drive the third fixed plate 38 to push the telescopic rod 37 and the spring 39 to produce deformation. At this time, the second fixed plate 36 transmits the pressure generated by the deformation to the pressure sensor 35. The stress conditions at multiple positions on the surface of the tensioning plate 27 are monitored through the multiple pressure sensors 35 arranged on the upper part of the tensioning plate 27. When the force on one side of the surface of the tensioning plate 27 is too large, it indicates that the tensioning force of the tensioning mechanism 2 on the cable is biased to one side, and it is necessary to increase the tension on the other side, or reduce the tension on one side, so that the cable is evenly stressed during the tensioning process.

[0062] Example 3: Please refer to Figure 8 The present invention provides a technical solution: a method for using asymmetric cable tensioning and fast fixing, comprising the following steps:

[0063] S1. Preparation for tensioning construction: prepare measuring tools and measure the length of the cable, prepare and debug the tensioning device, inspect the anchorage area of ​​the cable tower and the main beam, and determine the construction control parameters. The tensioning device itself can be disassembled into several components, and the several components can be gradually installed inside the cable tower according to the design steps;

[0064] The following steps are involved: preparing measuring tools and measuring the length of the cable, preparing and debugging the tensioning device, inspecting the anchorage area of ​​the cable tower and main beam, and determining the construction control parameters:

[0065] S11. Select a total station with a measurement accuracy of ±1 mm as a measuring instrument, and measure the length of the cable using the total station;

[0066] S12. According to the design cable force of the cable, select an appropriate tensioning device. The rated tension of the tensioning device should be greater than 1.3 times the maximum design cable force of the cable. The tensioning device should be debugged at the construction site;

[0067] S13. Check the concrete strength of the anchorage points of the cables on the towers and main beams, the size, flatness and corrosion resistance of the anchorage steel components, and clean up the debris around the anchorage area;

[0068] S14. Use bridge structure analysis software to build a finite element model of the bridge to analyze the stress state of the cables and the linear changes of the main beams at each construction stage. Based on the analysis results of the finite element model and combined with the design requirements, calculate the theoretical cable force values ​​of the cables to be tensioned. At the same time, correct the theoretical cable force values ​​according to the shrinkage, creep, and temperature changes of the concrete.

[0069] S2. Cable installation and construction: First, the cables are hoisted and threaded, and then the cable positions are adjusted;

[0070] First, the cable is hoisted and threaded, and then the position of the cable is adjusted, including the following steps:

[0071] S21. Selecting suitable lifting equipment according to the weight and length of the cable, wherein the lifting equipment is at least one of a crane and a tower crane;

[0072] S22, lifting one end of the cable to the top of the cable tower anchoring area by a lifting device, and then slowly lowering it, so that the anchor head of the cable is inserted into the anchor hole on the cable tower for temporary fixation, lifting the other end of the cable to the top of the main beam anchoring area, and then slowly lowering it, and inserting the anchor head into the anchor hole of the main beam to complete the cable threading;

[0073] S23. Use a hand chain hoist or a small jack to move the cable in the anchoring area, adjust the position of the cable in the anchoring area, and align the cable with the center line of the anchor hole by monitoring with a measuring tool to ensure that the deviation is no more than ±3mm;

[0074] S3, cable tensioning construction: firstly, the cables are tensioned initially, then tensioned in stages, and finally tensioned in the final stage;

[0075] First, the cable is initially tensioned, then the cable is tensioned in stages, and finally the cable is tensioned in the final stage, which includes the following steps:

[0076] S31. Use a tensioning device to fix and tension the cable. When the cable force of the cable reaches 30% of the tensioning design value, suspend tensioning and inspect the cable, anchoring area and tensioning device.

[0077] S32, dividing the tensioning process of the cable into multiple levels, the cable force increment of each level of tensioning is 15%-20% of the design cable force, and suspending the tensioning for 6-15 minutes after each level of tensioning is completed. When the cable force reaches 80% of the design cable force, suspending the tensioning and inspecting the cable, anchoring area and tensioning device;

[0078] S33, continue to tension the cable, and when the cable force reaches 95% of the design cable force, adjust the cable force increment to 1%-2% of the design cable force, and stop tensioning when the cable force reaches the design cable force;

[0079] S4, asymmetric cable tensioning construction: determine the tensioning sequence of the cables according to the design and construction control parameters, adjust the asymmetric cable force during the asymmetric tensioning process, and monitor, feedback and adjust the tensioning process at the same time;

[0080] Determine the tensioning sequence of the cables according to the design and construction control parameters, adjust the asymmetric cable force during the asymmetric tensioning process, and monitor, feedback and adjust the tensioning process, including the following steps:

[0081] S41. According to the length of the cable and the position on the main beam surface, the cable is gradually tensioned in the order of short first and long later, and inside first and outside later;

[0082] S42. When tensioning the subsequent cables, the cable force is adjusted according to the force distribution principle of asymmetric tensioning;

[0083] S43. During the cable tensioning process, monitor the vertical displacement, lateral displacement and torsion angle of the main beam, the cable force change of the tensioned cable and the stress in the anchorage area of ​​the main beam;

[0084] S5. Inspection and adjustment after cable tensioning: re-measure the cable force, check the elongation of the cable, check the main beam line shape and stress, and inspect and protect the anchorage area;

[0085] The following steps are included to re-measure the cable force, check the elongation of the cable, check the main beam line shape and stress, and inspect and protect the anchorage area:

[0086] S51. Establish measurement points at the middle and anchorage ends of the cable, use force measuring equipment to re-measure the cable force, compare the re-measured cable force with the designed cable force, and the deviation is no more than ±5% to be qualified;

[0087] S52. Calculate the theoretical elongation of the cable according to its actual cable force, elastic modulus and length, and compare it with the actual elongation measured during the tensioning process. The deviation is not more than ±6%, which is considered acceptable.

[0088] S53. Use a total station and a level to measure the elevation, mid-span deflection, and cantilever end displacement of the main beam;

[0089] S54. Strain gauges are arranged at the mid-span, support points and cable anchorage areas of the main beam to detect the stress of the main beam. The measured stress is compared with the design stress. The deviation is not more than ±5% and is considered acceptable.

[0090] S55. Check the anchor heads of the cables at the anchorage areas on the towers and main beams, the concrete condition of the anchorage areas, and the anti-corrosion coatings at the anchorage areas. At the same time, set up permanent protective devices around the anchorage areas. The protective devices are either protective covers or anti-corrosion coatings.

[0091] The working principle and use method of the present invention are as follows: the fixing bolts of the tensioning device embedded in the cable tower are fixedly connected by the installation base 11. After the installation base 11 is fixed, the tensioning mechanism 2 can accurately tension the cable. The installation plug rod 21 is plugged into the installation sleeve 15, and the tensioning mechanism 2 can be quickly installed on the upper part of the support mechanism 1. The tensioning end of the cable is inserted from the second connecting plate 22 and the bottom of the anchor plate 4, and then passed out from the center of the clamp 5. Then the tensioning jack 25 is lifted, driving the tensioning plate 27 and the tensioning limit plate 210 to pull the anchor plate 4. At this time, the clamp 5 is tightened along the inside of the anchor plate 4 to fix the cable, and the cable is tensioned following the movement of the anchor plate 4.

[0092] At the same time, when the tensioning device is installed in a particularly narrow space, the tensioning jack 25 can be removed from between the tensioning plate 27 and the second connecting plate 22, and the tensioning plate 27 can be removed from the upper part of the second connecting plate 22. During installation, the positioning base 24 is limited by the positioning frame 23, and then the tensioning jack 25 is quickly installed on the surface of the second connecting plate 22 using the fixing bolts. Then, the tensioning plate 27 is quickly positioned and installed by plugging the tensioning limiting plate 210 with the guide plate 29, and the tensioning plate 27 is quickly fixed by threading the tensioning plate 27 with the second supporting bracket 26 through the mounting bolts 28.

[0093] During the process of tensioning the cable, the tensioning plate 27 will move upward. At this time, the tensioning plate 27 will drive the third fixed plate 38 to push the telescopic rod 37 and the spring 39 to produce deformation. At this time, the second fixed plate 36 transmits the pressure generated by the deformation to the pressure sensor 35. The multiple pressure sensors 35 arranged on the upper part of the tensioning plate 27 monitor the stress conditions at multiple positions on the surface of the tensioning plate 27.

[0094] Although the present invention has been described in detail with reference to the aforementioned embodiments, it is still possible for those skilled in the art to modify the technical solutions described in the aforementioned embodiments, or to make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. An asymmetric cable tensioning quick fixing device, comprising a tensioning device, wherein the tensioning device comprises a supporting mechanism (1), a tensioning mechanism (2) is installed on the upper part of the supporting mechanism (1), and the characteristics are: An auxiliary mechanism (3) is installed on the upper part of the tensioning mechanism (2); the supporting mechanism (1) is used to fix the entire installation at the tensioning position of the cable tower; an anchor plate (4) is fixedly connected to the surface of the tensioning mechanism (2); an adapted clip (5) is arranged inside the anchor plate (4); the anchor plate (4) and the clip (5) are used to fix the tensioning end of the cable; the tensioning mechanism (2) is used to tension the cable; the auxiliary mechanism (3) is used for the tensioning mechanism (2) to monitor the uniformity of the tension when the cable is tensioned; The support mechanism (1) comprises a mounting base (11), the upper portion of the mounting base (11) is fixedly connected to a threaded sleeve (12), the inner portion of the threaded sleeve (12) is threadedly connected to a threaded support rod (13), the upper portion of the threaded support rod (13) is fixedly connected to a mounting sleeve (15), the tensioning mechanism (2) comprises a mounting plug rod (21), a mounting bolt (28) and a tensioning plate (27), the bottom of the mounting plug rod (21) is plugged into the mounting sleeve (15), and the top of the mounting plug rod (21) is fixedly connected to a second connecting plate (22), the upper portion of the second connecting plate (22) is fixedly connected to a positioning frame (23), the inner portion of the positioning frame (23) is plugged with a positioning base (24), the positioning base The bottom of the (24) is fitted with the second connecting plate (22), and the top of the positioning base (24) is fixedly connected with a tensioning jack (25), the top of the tensioning jack (25) is fixedly connected with a second supporting bracket (26), the upper part of the second supporting bracket (26) is threadedly connected with a mounting bolt (28), the tensioning plate (27) is fixedly connected with the second supporting bracket (26) through the mounting bolt (28), the upper part of the second connecting plate (22) is fixedly connected with a guide plate (29), the inner part of the guide plate (29) is slidably plugged with a tensioning limit plate (210), the tensioning limit plate (210) is fixedly connected to the bottom of the tensioning plate (27), and the side of the tensioning limit plate (210) is fixedly connected to the anchor plate (4).

2. The asymmetric cable tensioning quick fixing device according to claim 1, characterized in that: The mounting base (11) is provided with a No. 1 connecting plate (16), the upper portion of the No. 1 connecting plate (16) is fixedly connected to a supporting jack (17), the upper portion of the supporting jack (17) is fixedly connected to a No. 1 supporting bracket (18), the side of the mounting sleeve (15) is fixedly connected to a supporting plate (14), and the No. 1 supporting bracket (18) is fitted with the bottom of the supporting plate (14).

3. The asymmetric cable tensioning quick fixing device according to claim 2, characterized in that: A fixing bolt is threadedly connected to the side surface of the positioning frame (23), and the fixing bolt passes through the positioning frame (23) and is threadedly connected to the positioning base (24).

4. The asymmetric cable tensioning quick fixing device according to claim 3, characterized in that: The auxiliary mechanism (3) comprises an installation limit plate (31) and an installation plug plate (32), wherein the installation limit plate (31) is fixedly connected to the upper part of the second connection plate (22), the installation plug plate (32) is slidably plugged with the installation limit plate (31), and the upper part of the installation plug plate (32) is fixedly connected to a connecting frame (33), the side of the connecting frame (33) is fixedly connected to a first fixing plate (34), and the bottom of the first fixing plate (34) is fixedly connected to a pressure sensor (35), and the pressure sensor (35) A second fixing plate (36) is fixedly connected at the bottom, a telescopic rod (37) is fixedly connected at the bottom of the second fixing plate (36), a third fixing plate (38) is fixedly connected at the bottom of the telescopic rod (37), a spring (39) is arranged on the surface of the telescopic rod (37), one end of the spring (39) is fixedly connected to the second fixing plate (36), and the other end of the spring (39) is fixedly connected to the third fixing plate (38), and the third fixing plate (38) is in contact with the surface of the tensioning plate (27).

5. A method for using asymmetric cable tensioning and fast fixing, characterized in that: An asymmetric cable tensioning quick fixing device according to any one of claims 1 to 4 is used, comprising the following steps: S1. Preparation for tensioning construction: prepare measuring tools and measure the length of the cable, prepare and debug the tensioning device, inspect the anchorage area of ​​the cable tower and the main beam, and determine the construction control parameters. The tensioning device itself can be disassembled into several components, and the several components can be gradually installed inside the cable tower according to the design steps; S2. Cable installation and construction: First, the cables are hoisted and threaded, and then the cable positions are adjusted; S3, cable tensioning construction: firstly, the cables are tensioned initially, then tensioned in stages, and finally tensioned in the final stage; S4, asymmetric cable tensioning construction: determine the tensioning sequence of the cables according to the design and construction control parameters, adjust the asymmetric cable force during the asymmetric tensioning process, and monitor, feedback and adjust the tensioning process at the same time; S5. Inspection and adjustment after cable tensioning: re-measure the cable force, check the elongation of the cable, check the main beam line shape and stress, and inspect and protect the anchorage area.

6. The method for using asymmetric cable tensioning and fast fixing according to claim 5, characterized in that: In step S1, the steps of preparing a measuring tool and measuring the length of the cable, preparing a tensioning device and debugging the tensioning device, inspecting the anchorage area of ​​the cable tower and the main beam, and determining the construction control parameters include the following steps: S11. Select a total station with a measurement accuracy of ±1 mm as a measuring instrument, and measure the length of the cable using the total station; S12. According to the design cable force of the cable, select an appropriate tensioning device. The rated tension of the tensioning device should be greater than 1.3 times the maximum design cable force of the cable. The tensioning device should be debugged at the construction site; S13. Check the concrete strength of the anchorage points of the cables on the towers and main beams, the size, flatness and corrosion resistance of the anchorage steel components, and clean up the debris around the anchorage area; S14. Use bridge structure analysis software to build a finite element model of the bridge to analyze the stress state of the cables and the linear changes of the main beams at each construction stage. Based on the analysis results of the finite element model and combined with the design requirements, calculate the theoretical cable force values ​​of the cables to be tensioned. At the same time, correct the theoretical cable force values ​​according to the shrinkage, creep, and temperature changes of the concrete.

7. The method for using asymmetric cable tensioning and fast fixing according to claim 5, characterized in that: In step S2, the process of first lifting and threading the cable and then adjusting the position of the cable includes the following steps: S21. Selecting suitable lifting equipment according to the weight and length of the cable, wherein the lifting equipment is at least one of a crane and a tower crane; S22, lifting one end of the cable to the top of the cable tower anchoring area by a lifting device, and then slowly lowering it, so that the anchor head of the cable is inserted into the anchor hole on the cable tower for temporary fixation, lifting the other end of the cable to the top of the main beam anchoring area, and then slowly lowering it, and inserting the anchor head into the anchor hole of the main beam to complete the cable threading; S23. Use a hand winch or a small jack to move the cable in the anchoring area, adjust the position of the cable in the anchoring area, monitor with a measuring tool, align the cable with the center line of the anchor hole, and ensure that the deviation is no more than ±3mm.

8. The method for using asymmetric cable tensioning and fast fixing according to claim 5, characterized in that: In step S3, the process of first performing initial tensioning on the cable, then performing graded tensioning on the cable, and finally performing final tensioning on the cable comprises the following steps: S31. Use a tensioning device to fix and tension the cable. When the cable force of the cable reaches 30% of the tensioning design value, suspend tensioning and inspect the cable, anchoring area and tensioning device. S32, dividing the tensioning process of the cable into multiple levels, the cable force increment of each level of tensioning is 15%-20% of the design cable force, and suspending the tensioning for 6-15 minutes after each level of tensioning is completed. When the cable force reaches 80% of the design cable force, suspending the tensioning and inspecting the cable, anchoring area and tensioning device; S33, continue to tension the cable, and when the cable force reaches 95% of the design cable force, adjust the cable force increment to 1%-2% of the design cable force, and stop tensioning when the cable force reaches the design cable force.

9. The method for using asymmetric cable tensioning and fast fixing according to claim 5, characterized in that: In step S4, the tensioning sequence of the cables is determined according to the design and construction control parameters, the asymmetric cable force is adjusted during the asymmetric tensioning process, and the tensioning process is monitored, fed back and adjusted, including the following steps: S41. According to the length of the cable and the position on the main beam surface, the cable is gradually tensioned in the order of short first and long later, and inside first and outside later; S42. When tensioning the subsequent cables, the cable force is adjusted according to the force distribution principle of asymmetric tensioning; S43. During the cable tensioning process, monitor the vertical displacement, lateral displacement and torsion angle of the main beam, the change in the tension of the tensioned cables and the stress in the anchorage area of ​​the main beam.

10. The method for using asymmetric cable tensioning and fast fixing according to claim 5, characterized in that: In step S5, the re-measurement of the cable force, the verification of the elongation of the cable, the inspection of the main beam line shape and stress, and the inspection and protection of the anchorage area include the following steps: S51. Establish measurement points at the middle and anchorage ends of the cable, use force measuring equipment to re-measure the cable force, compare the re-measured cable force with the designed cable force, and the deviation is no more than ±5% to be qualified; S52. Calculate the theoretical elongation of the cable according to its actual cable force, elastic modulus and length, and compare it with the actual elongation measured during the tensioning process. The deviation is not more than ±6%, which is considered acceptable. S53. Use a total station and a level to measure the elevation, mid-span deflection, and cantilever end displacement of the main beam; S54. Strain gauges are arranged at the mid-span, support points and cable anchorage areas of the main beam to detect the stress of the main beam. The measured stress is compared with the design stress. The deviation is not more than ±5% and is considered acceptable. S55. Check the anchor heads of the cables at the anchorage areas on the towers and main beams, the concrete condition of the anchorage areas, and the anti-corrosion coatings at the anchorage areas. At the same time, set up permanent protective devices around the anchorage areas. The protective devices are either protective covers or anti-corrosion coatings.

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