Asymmetric cable force tensioning fast fixing device and use method

Abstract

The application discloses a kind of asymmetric cable force tensioning quick fixing device and use method, it is related to bridge cable tension technology field, including tensioning construction preparation, cable installation construction, cable tensioning construction, cable asymmetric tensioning construction and the inspection and adjustment after cable tensioning completion.The application aims at the tensioning construction of cable, and the tensioning device is designed into multiple modules that can be disassembled and assembled.When installed inside the cable tower, the modular design facilitates transportation and positioning in narrow and complex spaces, effectively solving the problem of space limitations, making the installation process more flexible, reducing the installation difficulties caused by narrow spaces, and more accurately adapting to the position and angle of the cable when fixedly connected with the cable, ensuring the accuracy and stability of the connection, reducing the uneven stress caused by improper connection, improving construction efficiency, shortening installation and preparation time, and reducing construction difficulty.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of bridge cable tension, in particular to an asymmetric cable force tensioning and rapid fixing device and a use method thereof. BACKGROUND

[0002] During the cantilever construction stage of a cable-stayed bridge, the main girder of the bridge is extended in sections. Due to the uneven load distribution of each construction stage, the asymmetric cable force tensioning can be used to balance the asymmetric load, prevent excessive deformation and internal force redistribution of the main girder, and through the asymmetric cable force tensioning construction method, the bridge can also cope with special load conditions, such as concentrated vehicle driving on one side of the bridge during bridge design, eccentric load wind load, etc. Through asymmetric cable force tensioning, the internal force and linear of the structure can be adjusted during the operation stage of the bridge, and the stability of the bridge can be improved.

[0003] In the prior art, due to the structural design characteristics of the cable-stayed bridge, the cables are inclinedly arranged between the main girder and the tower. The connection angle of the cable with the main girder and the tower is determined according to the structural design. In order to make the tension force applied by the jack during the cable force tensioning process more effectively transmitted along the direction of the cable, reduce the lateral component force, and at the same time avoid the excessive lateral component force during the tension process causing local wear and tear of the cable, affecting the service life and safety performance of the cable, it is necessary to accurately install the tensioning device at the set position inside the tower.

[0004] However, in the prior art, when the cable force of the cable is asymmetrically tensioned, the design of the tower mainly considers the structural stress and appearance factors. The internal space is only considered to accommodate necessary structural members and necessary construction operation space during design. However, during the construction operation process on site, due to the large volume of the counterforce support and the tension structure, during the actual operation process, both the installation accuracy and the installation stability need to be considered. It is difficult to quickly install in place in a narrow space and complete the tensioning operation, which leads to the fact that the cable cannot be quickly installed and fixed, affecting the entire construction process and subsequent construction progress. Since the cable is the main stressed member in structures such as cable-stayed bridges, its function is to transmit the load of the main girder to the tower. Therefore, if the cable cannot be quickly tensioned and fixed, the force flow transmission path of the entire structure will be incomplete, which will affect the overall stability of the structure. In particular, when encountering accidental loads such as wind load, the ability of the structure to resist external forces will be weakened, increasing the possibility of structural instability. SUMMARY

[0005] The purpose of the present application is to provide an asymmetric cable force tensioning quick fixing device and a use method, so as to solve the problem that in the construction process on site, due to the large volume of counterforce support and tension structure, in the actual operation process, both the installation precision and the installation stability need to be considered, it is difficult to quickly install in place in a small space, complete the tensioning operation, the cable cannot be quickly installed and fixed, and the whole construction process and subsequent construction progress are affected, because the cable is the main stressed member in the structure such as cable-stayed bridge, and its function is to transmit the load of the main beam to the cable tower, so the cable cannot be quickly tensioned and fixed, which will lead to the incomplete force flow transmission path of the whole structure, and affect the overall stability of the structure.

[0006] To achieve the above purpose, the present application provides the following technical scheme: an asymmetric cable force tensioning quick fixing device, comprising a tensioning device, the tensioning device comprising a supporting mechanism, a tensioning mechanism being installed on the upper part of the supporting mechanism, an auxiliary mechanism being installed on the upper part of the tensioning mechanism, the supporting mechanism being used for being integrally installed and fixed at the tensioning position of the cable tower, an anchor plate being fixedly connected to the surface of the tensioning mechanism, an adapted clamping piece being arranged in the anchor plate, the anchor plate and the clamping piece being used for fixing the tensioning end of the cable, the tensioning mechanism being used for tensioning the cable, and the auxiliary mechanism being used for monitoring the uniformity of the tensioning force of the cable when the tensioning mechanism tensions the cable.

[0007] The supporting mechanism comprises a mounting base, a threaded sleeve being fixedly connected to the upper part of the mounting base, a threaded supporting rod being threadedly connected to the inside of the threaded sleeve, and a mounting sleeve being fixedly connected to the upper part of the threaded supporting rod, the tensioning mechanism comprising a mounting plug rod, mounting bolts and a tensioning plate, the mounting plug rod being inserted into the mounting sleeve at the bottom, a No. 2 connecting plate being fixedly connected to the top of the mounting plug rod, a positioning frame being fixedly connected to the upper part of the No. 2 connecting plate, a positioning base being inserted into the positioning frame, the positioning base being attached to the bottom of the No. 2 connecting plate, a tensioning jack being fixedly connected to the top of the positioning base, a No. 2 supporting bracket being fixedly connected to the top of the tensioning jack, the mounting bolts being threadedly connected to the upper part of the No. 2 supporting bracket, the tensioning plate being fixedly connected to the No. 2 supporting bracket through the mounting bolts, a guide plate being fixedly connected to the upper part of the No. 2 connecting plate, a tensioning limiting plate being slidably inserted into the guide plate, the tensioning limiting plate being fixedly connected to the bottom of the tensioning plate, and the tensioning limiting plate being fixedly connected to the anchor plate.

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

[0009] Preferably, the positioning frame side is threadedly connected with a fixing bolt, and the fixing bolt is threadedly connected with the positioning base.

[0010] Preferably, the auxiliary mechanism comprises a mounting limiting plate, a mounting plug-in plate, a connecting frame, a No. 1 fixing plate, a No. 2 fixing plate, an extension rod, a No. 3 fixing plate and a spring.

[0011] A use method of the asymmetric cable force tensioning rapid fixing device, comprising the following steps:

[0012] S1, tensioning construction preparation: preparing measurement tools and measuring the length of the cable, preparing a tensioning device and debugging the tensioning device, checking the cable tower and main beam anchorage zone, and determining the construction control parameters, the tensioning device can be disassembled into several components, and the several components can be installed step by step inside the cable tower according to the design steps;

[0013] S2, cable installation construction: first, hoist and install the cable, and then adjust the position of the cable;

[0014] S3, cable tensioning construction: first, initially tension the cable, then tension the cable in stages, and finally tension the cable to the final tension;

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

[0016] S5, inspection and adjustment after cable tensioning: re-measure the cable force, check the elongation of the cable, check the main beam linear and stress, and check and protect the anchorage zone.

[0017] Preferably, in step S1, the preparation of measurement tools and the measurement of the length of the cable, the preparation of the tensioning device and the debugging of the tensioning device, the inspection of the cable tower and the main beam anchorage zone, and the determination of the construction control parameters comprise the following steps:

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

[0019] S12, according to the design cable force of the cable, select the appropriate tensioning device, the rated tension of the tensioning device should be greater than 1.3 times of the maximum design cable force, and the tensioning device is debugged on the construction site;

[0020] S13, check the concrete strength of the anchorage point of the cable on the tower and the main beam, the size of the anchoring steel member, the flatness and the corrosion prevention, and clean the sundries around the anchoring area;

[0021] S14, use the bridge structure analysis software to establish the finite element model of the bridge to analyze the stress state of each construction stage cable and the linear change of the main beam, and calculate the theoretical cable force value of the cable to be tensioned according to the finite element model analysis result and the design requirement, and correct the theoretical cable force value according to the shrinkage, creep and temperature change of the concrete.

[0022] Preferably, in step S2, the first hoisting and threading of the cable are performed, and then the position of the cable is adjusted, including the following steps:

[0023] S21, according to the weight and length of the cable, select the appropriate hoisting equipment, which is at least one of a crane or a tower crane;

[0024] S22, lift one end of the cable to above the anchoring area of the tower by the hoisting equipment, then slowly lower it, insert the anchoring head of the cable into the anchoring hole on the tower for temporary fixation, hoist the other end of the cable to above the anchoring area of the main beam, then slowly lower it, and insert the anchoring head into the anchoring hole of the main beam to complete the threading of the cable;

[0025] S23, use a hand-operated hoist or a small jack to move the cable in the anchoring area, adjust the position of the cable in the anchoring area, monitor by measuring tools, align the cable with the center line of the anchoring hole, and ensure that the deviation is not greater than ±3mm.

[0026] Preferably, in step S3, the initial tensioning of the cable is performed first, then the cable is tensioned in stages, and finally the cable is tensioned finally, including the following steps:

[0027] S31, use the tensioning device to fix the cable, and when the cable force reaches 30% of the design tensioning value, pause the tensioning, and check the cable, the anchoring area and the tensioning device;

[0028] S32, divide the tensioning process of the cable into multiple levels, and the cable force increment of each level is 15%-20% of the design cable force, pause the tensioning for 6-15 minutes after each level tensioning is completed, and when the cable force reaches 80% of the design cable force, pause the tensioning, and check the cable, the anchoring area and the tensioning device;

[0029] S33, continue tensioning the cable, when the cable force reaches 95% of the design cable force, the cable force increment range is adjusted to 1%-2% of the design cable force, until the cable force reaches the design cable force, and the tensioning is stopped.

[0030] Preferably, in step S4, the tensioning sequence of the cable is determined according to the design and construction control parameters, the asymmetric cable force is adjusted in the asymmetric tensioning process, and the tensioning process is monitored, fed back and adjusted, including the following steps:

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

[0032] S42, when the subsequent cable is tensioned, the cable force is adjusted according to the force value distribution principle of the asymmetric tensioning;

[0033] S43, during the tensioning of the cable, the vertical displacement, lateral displacement and torsion angle of the main beam, the cable force change of the tensioned cable and the stress of the anchoring area of the main beam are monitored.

[0034] Preferably, in step S5, the cable force is retested, the elongation of the cable is checked, the main beam alignment and stress are checked, and the anchoring area is checked and protected, including the following steps:

[0035] S51, measurement points are established at the middle and anchoring end positions of the cable, force measuring equipment is used to retest the cable force, the retested cable force is compared with the design cable force, and the deviation is not greater than ±5% for qualification;

[0036] S52, according to the actual cable force, elastic modulus and length of the cable, the theoretical elongation of the cable is calculated, and the actual elongation measured in the tensioning process is compared, and the deviation is not greater than ±6% for qualification;

[0037] S53, the elevation, mid-span deflection and cantilever end displacement of the main beam are measured using a total station and a level;

[0038] S54, strain gauges are arranged at the mid-span, support point and cable anchoring area of the main beam, the stress of the main beam is detected, the measured stress is compared with the design stress, and the deviation is not greater than ±5% for qualification;

[0039] S55, the anchoring head of the cable anchoring area on the tower and the main beam, the concrete state of the anchoring area and the anticorrosive coating of the anchoring area are checked, and at the same time, permanent protection devices are arranged around the anchoring area, and the protection devices are one of protection covers or anticorrosive coatings.

[0040] Compared with the prior art, the beneficial effects of the present application are:

[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 facilitates transportation and positioning in narrow and complex spaces, effectively solving the problem of space limitations, making the installation process more flexible, and reducing installation difficulties caused by limited space. At the same time, the fixed connection with the cable can more accurately adapt to the position and angle of the cable, ensuring the accuracy and stability of the connection, reducing uneven force caused by improper connection, improving construction efficiency, shortening installation and preparation time, and reducing construction difficulty. In addition, individual calibration and adjustment through modules is conducive to improving the overall accuracy of the tensioning device, ensuring the accuracy of cable tensioning, and better achieving the goal of load balance and linear control of the cantilever end of the main beam by asymmetric cable tensioning, thereby ensuring construction quality and structural safety.

[0042] 2. In this method, the mounting base is fixedly connected with the fixing bolts of the tensioning device embedded in the cable tower. After the mounting base is fixed, according to the height of several mounting sleeves, 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 mounting sleeve so that the height of the mounting 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 can be installed step by step. By splitting the tensioning mechanism for installation, the overall weight and volume during the installation process are reduced, which facilitates the rapid and accurate installation of the tensioning mechanism, thereby improving the speed of the cable tensioning construction.

[0043] 3. In this method, when the tensioning jack is lifting the tensioning plate, if the lifting pressure is large, the support jack is used to lift the No. 1 support bracket to support the bottom of the support plate, thereby providing stable support force for the tensioning jack. At the same time, the No. 1 connecting plate is used to increase the force-bearing area of ​​the bottom of the tensioning device, thereby avoiding pressure concentration in the anchoring area during the tensioning process. This can prevent the anchoring area from being subjected to excessive local pressure and causing concrete cracking and anchor failure, thereby ensuring reliable cable anchoring, maintaining the overall stability and safety of the structure, and extending 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 generate 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 enable the cable to give full play to its carrying capacity, effectively transfer the load, 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 and fast fixing device of the present invention;

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

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

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

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

[0051] Figure 7 This 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 provides 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 support 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 support bracket; 27, tensioning plate; 28, mounting bolt; 29, guide plate; 210, tensioning limiting plate; 3, auxiliary mechanism; 31, mounting limiting plate; 32, mounting plug plate; 33, connecting frame; 34, No. 1 fixed plate; 35, pressure sensor; 36, No. 2 fixed plate; 37, telescopic rod; 38, No. 3 fixed plate; 39, spring; 4, anchor plate; 5, clamping piece. DETAILED DESCRIPTION

[0054] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of protection of the present application.

[0055] Embodiment one: according to Figures 1-7 As shown in the figure, in step S1, the tensioning device includes a support mechanism 1, a tensioning mechanism 2 is mounted on the upper part of the support mechanism 1, an auxiliary mechanism 3 is mounted on the upper part of the tensioning mechanism 2, the support mechanism 1 is used to fix and install the whole in the tensioning position of the cable tower, an anchor plate 4 is fixedly connected to the surface of the tensioning mechanism 2, an adaptive clamping piece 5 is arranged in the anchor plate 4, the anchor plate 4 and the clamping piece 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 to monitor the uniformity of tension when the tensioning mechanism 2 tensions the cable;

[0056] The support mechanism 1 comprises a mounting base 11, a threaded sleeve 12 fixedly connected to the upper portion of the mounting base 11, a threaded support rod 13 threadedly connected in the threaded sleeve 12, and a mounting sleeve 15 fixedly connected to the upper portion of the threaded support rod 13. The tensioning mechanism 2 comprises a mounting plug rod 21, mounting bolts 28, and a tensioning plate 27. The bottom portion of the mounting plug rod 21 is inserted into the mounting sleeve 15, and the top portion 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. A positioning base 24 is inserted into the positioning frame 23. The bottom portion of the positioning base 24 is attached to the second connecting plate 22, and the top portion of the positioning base 24 is fixedly connected to a tensioning jack 25. The top portion of the tensioning jack 25 is fixedly connected to a second support bracket 26. The upper portion of the second support bracket 26 is threadedly connected to the mounting bolts 28. The tensioning plate 27 is fixedly connected to the second support bracket 26 through the mounting bolts 28. The upper portion of the second connecting plate 22 is fixedly connected to a guide plate 29. A tensioning limiting plate 210 is slidably inserted into the guide plate 29. The tensioning limiting plate 210 is fixedly connected to the bottom portion of the tensioning plate 27. The side surface of the tensioning limiting plate 210 is fixedly connected to the anchor plate 4. The mounting base 11 is installed with a first connecting plate 16. The upper portion of the first connecting plate 16 is fixedly connected to a support jack 17. The upper portion of the support jack 17 is fixedly connected to a first support bracket 18. The side surface of the mounting sleeve 15 is fixedly connected to a support plate 14. The first support bracket 18 is attached to the bottom portion of the support plate 14. The side surface of the positioning frame 23 is threadedly connected with a fixing bolt. The fixing bolt is threadedly connected with the positioning base 24 through the positioning frame 23.

[0057] In the embodiment, the mounting base 11 is fixedly connected with the fixing bolt of the tensioning device pre-buried in the cable tower. After the mounting base 11 is fixedly connected, the height of the several mounting sleeves 15 is adjusted by rotating the threaded support rod 13 and extending or retracting the threaded support rod 13 along the threaded sleeve 12, so that the height of the mounting sleeve 15 is accurate, thereby ensuring that the installation position of the tensioning mechanism 2 is accurate, and the tensioning mechanism 2 can accurately tension the cable. The mounting plug rod 21 is inserted into the mounting sleeve 15, so that the tensioning mechanism 2 can be quickly installed on the upper portion of the support mechanism 1. The tensioning end of the cable is inserted from the bottom portion of the second connecting plate 22 and the anchor plate 4 and then out from the center of the clamping piece 5. Then the tensioning jack 25 is jacked up to drive the tensioning plate 27 and the tensioning limiting plate 210 to pull the anchor plate 4. At this time, the clamping piece 5 is tightened along the inside of the anchor plate 4 to fix the cable. The anchor plate 4 is moved to complete the tensioning operation of the cable. In the process of moving the anchor plate 4, the tensioning limiting 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] Meanwhile, when the tensioning device is installed in a particularly narrow space, the tensioning jack 25 can be detached from between the tensioning plate 27 and the second connecting plate 22, and the tensioning plate 27 can be detached from the upper portion of the second connecting plate 22. When installation is performed, the positioning base 24 is limited by the positioning frame 23, and the tensioning jack 25 is quickly installed on the surface of the second connecting plate 22 by using the fixing bolt. Subsequently, the tensioning plate 27 is quickly positioned and installed by inserting the tensioning limiting plate 210 and the guide plate 29, and the tensioning plate 27 is quickly fixed by being screwed with the second supporting bracket 26 through the installation bolt 28. The tensioning mechanism 2 is split and installed, the overall weight and volume during installation are reduced, the tensioning mechanism 2 is quickly and accurately installed, and the speed of tensioning the cable during tensioning construction is improved.

[0059] When the tensioning jack 25 jacks up the tensioning plate 27, if the jacking pressure is large, the bottom of the supporting plate 14 is supported by jacking the first supporting bracket 18 through the supporting jack 17, so as to provide stable supporting force for the tensioning jack 25. Meanwhile, the stress area of the supporting force at the bottom of the tensioning device is increased by the first connecting plate 16, so as to avoid that the tensioning position of the cable tower is too concentrated, which causes damage to the cable tower, and avoid that the thread of the threaded supporting rod 13 and the threaded sleeve 12 is deformed, which affects the next use.

[0060] Embodiment two: according to Figures 1-7 As shown in the figure, the auxiliary mechanism 3 includes an installation limiting plate 31 and an installation plug plate 32. The installation limiting plate 31 is fixedly connected to the upper portion of the second connecting plate 22. The installation plug plate 32 is slidably inserted into the installation limiting plate 31. The upper portion of the installation plug plate 32 is fixedly connected with a connecting frame 33. The side surface of the connecting frame 33 is fixedly connected with a first fixed plate 34. The bottom of the first fixed plate 34 is fixedly connected with a pressure sensor 35. The bottom of the pressure sensor 35 is fixedly connected with a second fixed plate 36. The bottom of the second fixed plate 36 is fixedly connected with an extension rod 37. The bottom of the extension rod 37 is fixedly connected with a third fixed plate 38. The surface of the extension rod 37 is provided with a spring 39. One end of the spring 39 is fixedly connected with the second fixed plate 36. The other end of the spring 39 is fixedly connected with the third fixed plate 38. The third fixed plate 38 is attached to the surface of the tensioning plate 27.

[0061] In the process of tensioning the cable, the tensioning plate 27 will move upwards, at this time the tensioning plate 27 will drive the No. 3 fixing plate 38 to push the telescopic rod 37 and the spring 39 to deform, at this time the No. 2 fixing plate 36 will transmit the pressure generated by the deformation to the pressure sensor 35, the tensioning plate 27 is provided with a plurality of pressure sensors 35 on the upper portion, the force conditions of a plurality of positions on the surface of the tensioning plate 27 are monitored, when the force on one side of the surface of the tensioning plate 27 is too large, it indicates that the tensioning mechanism 2 is biased to one side when tensioning the cable, 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 uniformly stressed during tensioning.

[0062] Embodiment three: please refer to Figure 8 The application provides a technical solution: a use method of an asymmetric cable tensioning rapid fixing, comprising the following steps:

[0063] S1, tensioning construction preparation: preparing measurement tools and measuring the length of the cable, preparing a tensioning device and debugging the tensioning device, checking the anchorage zone of the cable tower and the main beam, and determining the construction control parameters, the tensioning device itself can be disassembled into several components, and the several components can be installed step by step inside the cable tower according to the design steps;

[0064] Preparing measurement tools and measuring the length of the cable, preparing a tensioning device and debugging the tensioning device, checking the anchorage zone of the cable tower and the main beam, and determining the construction control parameters comprise the following steps:

[0065] S11, a total station with a measurement accuracy of ±1mm is selected as a measuring instrument, and the length of the cable is measured by the total station;

[0066] S12, according to the design cable force of the cable, a suitable tensioning device is selected, the rated tension of the tensioning device should be greater than 1.3 times the maximum design cable force of the cable, and the tensioning device is debugged on the construction site;

[0067] S13, the concrete strength of the anchorage point of the cable on the cable tower and the main beam, the size of the anchoring steel member, the flatness and the corrosion prevention situation are checked, and the sundries around the anchorage zone are cleaned;

[0068] S14, a bridge structure analysis software is used to establish a finite element model of the bridge to analyze the stress state of the cable and the linear change of the main beam in each construction stage, and according to the analysis results of the finite element model and the design requirements, the theoretical cable force value of the cable to be tensioned is calculated, and the theoretical cable force value is corrected according to the shrinkage, creep and temperature change of the concrete.

[0069] S2, cable installation construction: first, the cable is hoisted and the cable is installed, then the position of the cable is adjusted;

[0070] Firstly, the cable is hoisted and the cable is constructed, and then the cable position is adjusted, including the following steps:

[0071] S21, according to the weight and length of the cable, select the appropriate hoisting equipment, hoisting equipment is at least one of the crane or tower crane;

[0072] S22, one end of the cable is lifted to the cable tower anchorage zone above by hoisting equipment, and then slowly lowered, so that the anchoring head of the cable is inserted into the anchoring hole on the cable tower for temporary fixation, and the other end of the cable is hoisted to the main beam anchorage zone, and then slowly lowered, and the anchoring head is inserted into the anchoring hole of the main beam to complete the cable construction;

[0073] S23, use a hand-operated hoist or a small jack to move the cable in the anchorage zone, adjust the position of the cable in the anchorage zone, and monitor by measuring tools, so that the cable is aligned with the center line of the anchoring hole, and the deviation is not more than ± 3mm;

[0074] S3, cable tensioning construction: firstly, the cable is initially tensioned, then the cable is tensioned in stages, and finally the cable is tensioned;

[0075] Firstly, the cable is initially tensioned, then the cable is tensioned in stages, and finally the cable is tensioned, including the following steps:

[0076] S31, use the tensioning device to fix the cable, and when the cable force reaches 30% of the tensioning design value, stop tensioning, and check the cable, anchorage zone and tensioning device;

[0077] S32, the cable tensioning process is divided into multiple levels, and the cable force increment of each level is 15%-20% of the design cable force, and after each level tensioning is completed, the tensioning is paused for 6-15 minutes, and when the cable force reaches 80% of the design cable force, the tensioning is paused, and the cable, anchorage zone and tensioning device are checked;

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

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

[0080] According to the design and construction control parameters, the tensioning sequence of the cable is determined, the asymmetric cable force is adjusted in the asymmetric tensioning process, and the tensioning process is monitored, fed back and adjusted, including the following steps:

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

[0082] S42, when tensioning the subsequent cable, the cable force is adjusted according to the force value distribution principle of asymmetric tensioning;

[0083] S43, during the tensioning of the cable, the vertical displacement, lateral displacement and torsion angle of the main beam, the change of the cable force of the tensioned cable and the stress of the anchoring area of the main beam are monitored;

[0084] S5, inspection and adjustment after the tensioning of the cable is completed: re-measuring the cable force, checking the elongation of the cable, checking the linear shape and stress of the main beam, and checking and protecting the anchoring area;

[0085] Re-measuring the cable force, checking the elongation of the cable, checking the linear shape and stress of the main beam, and checking and protecting the anchoring area include the following steps:

[0086] S51, measurement points are established at the middle and anchoring end positions of the cable, force measuring equipment is used to re-measure the cable force, the re-measured cable force is compared with the designed cable force, and the deviation is not more than ± 5% for qualified;

[0087] S52, according to the actual cable force, elastic modulus and length of the cable, the theoretical elongation of the cable is calculated, and compared with the actual elongation measured during the tensioning process, and the deviation is not more than ± 6% for qualified;

[0088] S53, total station and level are used 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 point and cable anchoring area of the main beam to detect the stress of the main beam, the measured stress is compared with the designed stress, and the deviation is not more than ± 5% for qualified;

[0090] S55, the anchoring head of the cable at the anchoring area on the tower and the main beam, the concrete state of the anchoring area and the anticorrosion coating of the anchoring area are checked, and at the same time, permanent protection devices are arranged around the anchoring area, and the protection devices are one of protection covers or anticorrosion coatings.

[0091] The working principle and use method of the application: through the fixing and connecting of the installation base 11 and the fixing bolt of the pre-embedded tensioning device in the cable tower, the tensioning mechanism 2 can accurately tension the cable after the installation base 11 is fixed, the installation rod 21 is inserted into the installation sleeve 15, the tensioning mechanism 2 can be quickly installed on the upper part of the supporting mechanism 1, the tensioning end of the cable is inserted from the bottom of the second connecting plate 22 and the anchor plate 4 and then is pulled out from the center of the clamping piece 5, then the tensioning jack 25 is jacked, the tensioning plate 27 and the tensioning limiting plate 210 drive the anchor plate 4 to be pulled, at this time, the clamping piece 5 is tightened along the inside of the anchor plate 4 to fix the cable, and the cable is tensioned along with the movement of the anchor plate 4;

[0092] Meanwhile, when the tensioning device is installed in a particularly narrow space, the tensioning jack 25 can be detached from between the tensioning plate 27 and the second connecting plate 22, and the tensioning plate 27 can be detached from the upper part of the second connecting plate 22, when installing, the positioning base 24 is limited by the positioning frame 23, then the tensioning jack 25 is quickly installed on the surface of the second connecting plate 22 by using the fixing bolt, then the tensioning plate 27 is quickly positioned and installed by inserting the tensioning limiting plate 210 into the guide plate 29, and the tensioning plate 27 is quickly fixed by screwing the installation bolt 28 with the second supporting bracket 26.

[0093] In the process of tensioning the cable, the tensioning plate 27 will move upwards, at this time, the tensioning plate 27 will drive the third fixing plate 38 to push the telescopic rod 37 and the spring 39 to deform, at this time, the second fixing plate 36 transmits the pressure generated by the deformation to the pressure sensor 35, and the stress conditions of multiple positions on the surface of the tensioning plate 27 are monitored by the multiple pressure sensors 35 arranged on the upper part of the tensioning plate 27.

[0094] Although the application has been described in detail with reference to the foregoing embodiments, those skilled in the art can modify the technical solutions recorded in the foregoing embodiments or equivalently replace part of the technical features, and any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the application shall be included in the protection scope of the application.

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 mounted on the upper portion of the supporting mechanism (1), and is characterized in that: 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 provided 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 by the tensioning mechanism (2) to monitor the uniformity of the tension when the cable is tensioned; The support mechanism (1) includes 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) includes a mounting plug rod (21), a mounting bolt (28) and a tensioning plate (27), the bottom portion of the mounting plug rod (21) is plugged into the mounting sleeve (15), and the top portion 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 No. 2 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 the No. 2 support bracket (26), the upper part of the No. 2 support bracket (26) is threadedly connected with a mounting bolt (28), the tensioning plate (27) is fixedly connected to the No. 2 support bracket (26) through the mounting bolt (28), the upper part of the No. 2 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: The side surface 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).

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 portion of the second connecting plate (22), the installation plug plate (32) is slidably plugged into the installation limit plate (31), and the upper portion 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), 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 to the bottom of the second fixing plate (36), a telescopic rod (37) is fixedly connected to the bottom of the telescopic rod (37), a third fixing plate (38) is fixedly connected to the bottom of the telescopic rod (37), a spring (39) is provided 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 rapid fixation, characterized by: 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 cable tower and main beam anchorage area, and determine the construction control parameters. The tensioning device itself can be disassembled into several components, and the components can be gradually installed inside the cable tower according to the designed steps; S2. Cable installation: First, hoist and thread the cables, then adjust their positions; S3, cable tensioning construction: first, perform initial tensioning on the cables, then perform graded tensioning on the cables, and finally perform final tensioning on the cables; S4. Asymmetric cable tensioning construction: Determine the tensioning sequence of the cables based on the design and construction control parameters, adjust the asymmetric cable force during the asymmetric tensioning process, and monitor, provide feedback, and make adjustments to the tensioning process. 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. Select an appropriate tensioning device based on the designed cable force. The rated tension of the tensioning device should be greater than 1.3 times the maximum designed cable force of the cable. Debug the tensioning device 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 clear any debris around the anchorage areas. 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 finite element model analysis results 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 rapid fixation according to claim 5, characterized in that: In step S2, the process of first hoisting and threading the cable and then adjusting the position of the cable includes the following steps: S21. Selecting an appropriate lifting device based on the weight and length of the cable, wherein the lifting device is at least one of a crane and a tower crane; S22. One end of the cable is lifted to above the anchorage area of ​​the cable tower using a lifting device, and then slowly lowered so that the anchorage head of the cable is inserted into the anchorage hole on the cable tower for temporary fixation. The other end of the cable is lifted to above the anchorage area of ​​the main beam, and then slowly lowered so that the anchorage head is inserted into the anchorage hole of the main beam to complete the cable threading. S23. Use a hand hoist or small jack to move the cable in the anchoring area, adjust the position of the cable in the anchoring area, monitor with measuring tools, and align the cable with the center line of the anchor hole to ensure that the deviation is no more than ±3mm.

8. The method for using asymmetric cable tensioning and rapid fixation according to claim 5, characterized in that: In step S3, the process of initially tensioning the cables, then performing graded tensioning on the cables, and finally performing final tensioning on the cables comprises the following steps: S31. Use a tensioning device to securely tension the cable. When the cable force reaches 30% of the tensioning design value, suspend tensioning and inspect the cable, anchorage area, and tensioning device. S32. The cable tensioning process is divided into multiple levels, with the cable force increment for each level being 15%-20% of the design cable force. After each level of tensioning is completed, the tensioning is suspended for 6-15 minutes. When the cable force reaches 80% of the design cable force, the tensioning is suspended and the cable, anchorage area, and tensioning device are inspected. S33. Continue to tension the cable. When the cable force reaches 95% of the design cable force, adjust the cable force increment to 1%-2% of the design cable force. 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, 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, providing feedback, and adjusting the tensioning process include the following steps: S41. According to the length of the cables and their positions on the main beam surface, the cables are gradually tensioned in the order of short cables first, long cables later, and inner cables first, outer cables later; S42. When tensioning subsequent cables, adjust the cable forces 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 rapid fixation according to claim 5, characterized in that: In step S5, the re-measurement of cable force, verification of cable elongation, inspection of main beam linearity and stress, and inspection and protection of anchorage areas include the following steps: S51. Establish measurement points at the middle of the cable and at the anchor end. Use force measuring equipment to re-measure the cable tension. Compare the re-measured tension with the designed tension. A deviation of no more than ±5% is considered acceptable. S52. Calculate the theoretical elongation of the cable based on its actual cable force, elastic modulus, and length. Compare this with the actual elongation measured during the tensioning process. A deviation of no more than ±6% is considered acceptable. S53. Use a total station and level to measure the main beam elevation, mid-span deflection, and cantilever end displacement; S54. Place strain gauges at the mid-span, support points, and cable anchorage areas of the main beam to test the stress of the main beam. Compare the measured stress with the design stress. A deviation of no more than ±5% is considered acceptable. S55. Inspect the anchorage 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, install permanent protective devices around the anchorage areas. The protective devices are either protective covers or anti-corrosion coatings.

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