Suspension bridge cable clamp screw axial force detection and re-twisting integrated device and method

Abstract

The invention relates to the technical field of bridge structure safety maintenance, and discloses a suspension bridge cable clamp screw axial force detection and re-screwing integrated device and method, and the device comprises a strut angle, a nut sleeve, a jack, a connecting piece, a re-screwing rod, a displacement meter, a displacement meter support, and a magnet. The strut angle is matched with the cable clamp to provide an overall assembly foundation, the connecting piece is matched with the screw and used for connecting the screw and the jack, the jack applies tensioning acting force to the screw through the strut angle, the displacement meter is fixed to the cable clamp through the magnet and used for detecting displacement information in the tensioning process of the screw, and the nut sleeve is matched with a nut of the screw in a matched mode. And the re-screwing rod can penetrate through the strut angle and is matched with the nut sleeve to fasten the screw rod. The suspension bridge cable clamp screw axial force detection and re-twisting integrated device and method are used for accurately measuring the screw axial force, timely knowing the cable clamp screw axial force state and timely conducting fastening and re-twisting so as to guarantee the bridge structure safety in the operation period.

Description

Technical Field

[0001] This invention relates to the field of bridge structural safety maintenance technology, specifically to an integrated device and method for detecting and re-tightening the axial force of suspension bridge cable clamp bolts. Background Technology

[0002] In my country, with the rapid development of bridge theory and construction technology, suspension bridges are being widely used in the construction of bridges spanning rivers, seas, and mountainous areas. However, with the increase in operating time, due to the influence of long-term dynamic loads and material creep, construction defects and shrinkage effects, environmental erosion and stress relaxation, the cable clamp bolts of suspension bridges generally suffer from axial force loss, which in turn affects the stability of the connection between the main cable and the suspenders and the overall load-bearing performance of the bridge. To ensure the safe operation of the bridge, the most effective method to understand the actual axial force of the cable clamp bolts and tighten them in a timely manner is to accurately measure and re-tighten the bolt axial force.

[0003] The measurement and re-tightening of the axial force of the cable clamp screw generally includes the following four steps: ① Install the tensioning equipment on site; ② Measure the initial state data; ③ Tension in stages and record the measurement data; ④ Calculate the tightening axial force; ⑤ Determine whether the actual axial force meets the design requirements; ⑥ Confirm whether re-tightening is required.

[0004] Common methods for measuring screw axial force include ultrasonic testing, pull-out testing, and torque wrench testing. However, all of these methods have drawbacks. For example, ultrasonic testing is greatly affected by temperature, requires external calibration for parameter calculation, and necessitates tensioning equipment, making it cumbersome and posing a high risk of working at heights. Pull-out testing relies heavily on manual judgment, leading to significant measurement errors, and repeated pulling may damage the screw or cable clamp structure. Torque wrench testing requires presetting a torque coefficient before testing, which is highly dependent on the structural condition and difficult to obtain accurately, resulting in low measurement accuracy. Furthermore, regular wrench calibration is required, making the process complex. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention proposes an integrated device and method for detecting and re-tightening the axial force of cable clamp screws in suspension bridges. This device measures the axial force of the screws, allows for timely understanding of the axial force status of the cable clamp screws, and enables timely tightening and re-tightening to ensure the structural safety of the bridge during operation.

[0006] Firstly, an integrated device for detecting and re-tightening the axial force of suspension bridge cable clamp bolts is provided, including: support bracket, nut sleeve, jack, connector, re-tightening rod, displacement gauge, displacement gauge bracket and magnet; The support angle cooperates with the cable clamp to provide a foundation for overall assembly. The connector cooperates with the screw and is used to connect the screw and the jack. The jack applies a tensioning force to the screw based on the support angle. The displacement gauge is fixed to the cable clamp by a magnet and is used to detect the displacement information of the screw during the tensioning process. The nut sleeve is adapted to the nut of the screw. The re-tightening rod can pass through the support angle and cooperates with the nut sleeve to achieve screw fastening.

[0007] Furthermore, the support angle is detachably connected to the cable clamp, the support angle is provided with a re-tightening hole for the re-tightening rod to pass through, and the jack is mounted between the support angle and the connecting piece.

[0008] Furthermore, the displacement gauge bracket is connected to a magnet, the displacement gauge is mounted on the displacement gauge bracket, and the detection end of the displacement gauge is in contact with the connector.

[0009] Furthermore, the nut sleeve is fitted onto the outside of the nut on the screw, and the re-tightening rod passes through the re-tightening hole of the support angle and connects to the nut sleeve.

[0010] Furthermore, the connector is connected to the end of the screw away from the cable clamp via an internal thread. One end of the connector abuts against the jack, and the other end corresponds to the detection end of the displacement gauge.

[0011] Secondly, a method for detecting and re-tightening the axial force of suspension bridge cable clamp bolts is provided, based on the integrated device for detecting and re-tightening the axial force of suspension bridge cable clamp bolts described in any of the preceding items, including: The screw axial force is tested and tightened to meet the standard by assembling the device components, calibrating the displacement gauge, performing graded tensioning and recording data, fitting the curve to solve the axial force, re-tightening and secondary testing.

[0012] Furthermore, the operation of the assembly device components is as follows: the support angle, nut sleeve, jack, connector, re-tightening rod, displacement gauge, displacement gauge bracket and magnet are respectively assembled on the cable clamp and screw rod, so that the support angle is connected to the cable clamp, the connector is threadedly connected to the screw rod, the jack is clamped between the support angle and the connector, the displacement gauge is fixed to the cable clamp through the displacement gauge bracket and magnet, and the detection end of the displacement gauge is in contact with the connector, and the re-tightening rod can pass through the re-tightening hole of the support angle and cooperate with the nut sleeve.

[0013] Furthermore, the operation of calibrating the displacement gauge is as follows: after placing the displacement gauge at the corresponding position on the top of the connector, the displacement gauge is calibrated and adjusted.

[0014] Furthermore, the operation of graded tensioning and data recording is as follows: the screw is tensioned in stages using a jack, and the tension force value corresponding to each stage of tensioning and the vertical displacement value of the screw collected by the displacement gauge are recorded simultaneously. The operation of solving the axial force by fitting the curve is as follows: based on the recorded tension force and vertical displacement values, a screw displacement-tension force curve is fitted, and the actual axial force of the screw is obtained by calculating the coordinate values ​​of the intersection point of the two curves at different tension stages.

[0015] Furthermore, the re-tightening and secondary inspection operation is as follows: compare the actual axial force of the screw with the design axial force. If the actual axial force does not meet the design requirements, the screw is tightened by rotating the nut sleeve through the re-tightening rod passing through the re-tightening hole of the support angle. After tightening, perform staged tensioning again, record the data, and fit the curve to solve for the axial force until the screw axial force is restored to the design axial force.

[0016] The invention employing the above technical solution has the following advantages: This invention accurately measures the vertical deformation displacement of cable clamp bolts by using high-precision displacement gauges and pressure gauges. Based on the recorded jack tension Ti and corresponding vertical displacement Δli value during the cable clamp bolt tensioning process, the coordinates of the recorded points are plotted using MATLAB software. Then, a curve fitting algorithm is used to fit a function equation to the recorded point coordinates, and finally, the coordinates of the intersection points of different function equations are calculated. This allows for the rapid and accurate determination of the axial force T0 of the cable clamp bolt. Compared with the design axial force, bolts with unsatisfactory axial forces are promptly re-tightened and re-measured to ensure they return to the design value. This measurement method has advantages such as integrated measurement and re-tightening, reusable measuring equipment, convenient disassembly, fast measurement speed, high accuracy, and timely maintenance, and is expected to provide a new approach for the measurement and fastening of axial forces in bridge cable clamp bolts. Attached Figure Description

[0017] To more clearly illustrate the specific embodiments of the present invention, the accompanying drawings used in the specific embodiments will be briefly described below. In all the drawings, the elements or parts are not necessarily drawn to scale.

[0018] Figure 1 This is a flowchart of the integrated device and method for detecting and re-tightening the axial force of suspension bridge cable clamp screws according to the present invention; Figure 2 This is a diagram showing the arrangement of the displacement gauge and tensioning device in the integrated device and method for detecting and re-tightening the axial force of the cable clamp screw in the suspension bridge of the present invention. Figure 3 This is a force analysis diagram of the cable clamp screw in the integrated device and method for axial force detection and re-tightening of cable clamp screw in the present invention; Figure 4 This is a schematic diagram of the calculation of the axial force of the cable clamp screw in the integrated device and method for detecting and re-tightening the axial force of the cable clamp screw in the present invention; Figure 5This is a schematic diagram illustrating an example of calculating the axial force of the cable clamp screw in the integrated device and method for detecting and re-tightening the axial force of the cable clamp screw in the present invention.

[0019] Figure label: 1. Screw; 2. Nut; 3. Cable clamp; 4. Magnet; 5. Displacement gauge bracket; 6. Displacement gauge; 7. Nut sleeve. 8. Support angle, 9. Re-tightening hole, 10. Re-tightening rod, 11. Jack, 12. Connector. Detailed Implementation

[0020] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0021] The terms "first," "second," etc., in the specification, claims, and accompanying drawings of this application are used to distinguish different objects, not to describe a specific order. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or apparatus that includes a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to these processes, methods, products, or apparatuses.

[0022] like Figures 1-5 As shown, the integrated device for detecting and re-tightening the axial force of the suspension bridge cable clamp screw of the present invention includes: a support angle 8, a nut sleeve 7, a jack 11, a connector 12, a re-tightening rod 10, a displacement meter 6, a displacement meter bracket 5, and a magnet 4. The support angle 8 cooperates with the cable clamp 3 to provide a foundation for overall assembly. The cable clamp 3 (including the upper cable clamp and the lower cable clamp) and the connector 12 cooperate with the screw 1. The screw 1 (including the upper screw pair, the middle screw and the lower screw pair) is used to connect the screw 1 and the jack 11. The jack 11 applies a tensioning force to the screw 1 by relying on the support angle 8. The displacement gauge 6 is fixed to the upper cable clamp by the magnet 4 and is used to detect the displacement information of the screw 1 during the tensioning process. The nut sleeve 7 is adapted to the nut 2 of the screw 1. The nut 2 (including the upper nut and the lower nut) is connected to the upper nut by the nut sleeve 7. The re-tightening rod 10 drives the nut 2 to rotate through the nut sleeve 7. The re-tightening rod 10 can pass through the support angle 8 and cooperate with the nut sleeve 7 to achieve the tightening of the screw 1.

[0023] In this embodiment, the support angle 8 and the cable clamp 3 are detachably connected. The support angle 8 is provided with a re-tightening hole 9 for the re-tightening rod 10 to pass through. The jack 11 is set between the support angle 8 and the connector 12.

[0024] In this embodiment, the displacement gauge bracket 5 is connected to the magnet 4, the displacement gauge 6 is mounted on the displacement gauge bracket 5, and the detection end of the displacement gauge 6 is in contact with the connector 12.

[0025] In this embodiment, the nut sleeve 7 is sleeved on the outside of the nut 2 of the screw 1, and the re-tightening rod 10 passes through the re-tightening hole 9 of the support angle 8 and is connected to the nut sleeve 7.

[0026] In this embodiment, the connector 12 is connected to the end of the screw 1 away from the cable clamp 3 via an internal thread. The bottom end of the connector 12 abuts against the jack 11, and the top end corresponds to the detection end of the displacement gauge 6.

[0027] Specifically, the support angle 8 and the cable clamp 3 are detachably connected (such as by bolts). The support angle 8 has a re-tightening hole 9 for the re-tightening rod 10 to pass through. The position of the re-tightening hole 9 is directly opposite to the position of the screw 1 and the nut 2, so that the re-tightening rod 10 can be connected to the nut sleeve 7. The jack 11 is set between the support angle 8 and the connector 12. Its lower end is in contact with the top surface of the support angle 8, and its upper end is in contact with the bottom surface of the connector 12, forming a stable tension force system.

[0028] The magnet 4 is attached to the outer surface of the upper cable clamp 3. The displacement gauge bracket 5 is connected to the magnet 4 by welding, so that the connection is firm and there is no relative displacement. The displacement gauge 6 is mounted on the displacement gauge bracket 5, and its detection end is in close contact with the top surface of the connector 12, which can collect the vertical displacement generated by the connector 12 driving the screw 1 in real time.

[0029] The nut sleeve 7 is fitted on the outside of the nut 2 of the screw 1, and the two form a tight fit; the re-tightening rod 10 passes through the re-tightening hole 9 on the support angle 8 and is detachably connected to the nut sleeve 7 (such as a slot connection). Rotating the re-tightening rod 10 can drive the nut sleeve 7 and the nut 2 of the screw 1 to rotate synchronously, thereby tightening the screw 1.

[0030] The connector 12 is threaded to the end of the screw 1 away from the cable clamp 3 via an internal thread and is tightened to a state without gaps. The lower end of the connector 12 abuts against the upper end face of the jack 11, and the upper end face corresponds to the detection end of the displacement gauge 6. The vertical displacement of the screw 1 can be transmitted to the displacement gauge 6 through the connector 12.

[0031] In other embodiments, a method for detecting and re-tightening the axial force of suspension bridge cable clamp bolts is provided, and an integrated device for detecting and re-tightening the axial force of suspension bridge cable clamp bolts based on any of the preceding embodiments includes: The axial force of screw 1 is tested and tightened to meet the standard by assembling the components, calibrating the displacement gauge 6, performing graded tensioning and recording data, fitting the curve to solve the axial force, re-tightening and secondary testing.

[0032] In this embodiment, the assembly device components are operated as follows: the support angle 8, nut sleeve 7, jack 11, connector 12, re-tightening rod 10, displacement gauge 6, displacement gauge bracket 5, and magnet 4 are respectively assembled onto the cable clamp 3 and screw 1, so that the support angle 8 is connected to the cable clamp 3, the connector 12 is threadedly connected to the screw 1, the jack 11 is clamped between the support angle 8 and the connector 12, the displacement gauge 6 is fixed to the cable clamp 3 through the displacement gauge bracket 5 and the magnet 4, and the detection end of the displacement gauge 6 is in contact with the connector 12, and the re-tightening rod 10 can pass through the re-tightening hole 9 of the support angle 8 and cooperate with the nut sleeve 7.

[0033] Specifically, before preparing the tensioning screw 1, arrange the support angle 8, nut sleeve 7, jack 11, connector 12, magnet 4, bracket, and displacement gauge 6; A displacement gauge 6 (with an accuracy of 0.01 mm) is installed at the top of the connector 12. The displacement gauge 6 is accurately calibrated and adjusted to measure the vertical displacement of the anchor bolt 1. The jack is tensioned in 11 stages. When the vertical displacement of screw 1 begins to increase significantly, at least 4 more stages of tensioning are required. At the same time, the tension force and the corresponding vertical displacement of screw 1 are recorded during each stage of tensioning. Based on the recorded data, the displacement-tension force curve of screw 1 is fitted, the coordinate values ​​of the curve intersection point are calculated, and the axial force value of screw 1 is obtained accurately. Compare the accurately measured axial force of screw 1 with the design axial force. If it is less than 70% of the design axial force, the screw 1 should be tightened by using the re-tightening parts (nut sleeve 7, re-tightening rod 10) to rotate nut 2. The axial force of screw 1 should be measured again to restore it to the design axial force.

[0034] In this embodiment, the operation of calibrating displacement gauge 6 is as follows: after placing displacement gauge 6 at the corresponding position on the top of connector 12, displacement gauge 6 is calibrated and adjusted.

[0035] Specifically, following the operating instructions for displacement gauge 6, connect it to the calibration equipment to calibrate the measurement range and accuracy of displacement gauge 6, and ensure that its measurement error is within the allowable range; Apply a small preload to the connector 12 and observe whether the displacement gauge 6 can provide real-time feedback on displacement changes to verify the contact reliability between the detection end and the connector 12. After debugging, displacement gauge 6 is zeroed, ensuring accurate initial measurement and laying the foundation for subsequent displacement data acquisition. The core purpose of this step is to eliminate the inherent error of displacement gauge 6 and the measurement deviation caused by contact gap, thereby improving the accuracy of vertical displacement measurement of screw 1.

[0036] In this embodiment, the operation of graded tensioning and data recording is as follows: the screw 1 is tensioned in stages by the jack 11, and the tension force value corresponding to each stage of tensioning and the vertical displacement value of the screw 1 collected by the displacement gauge 6 are recorded simultaneously. The operation of fitting the curve to solve the axial force is as follows: based on the recorded tension force and vertical displacement values, a displacement-tension force curve of screw 1 is fitted. By calculating the coordinate values ​​of the intersection point of the two curves at different tension stages, the actual axial force of screw 1 is obtained.

[0037] Specifically, the screw 1 is tensioned in stages by jack 11. After each load is applied, it is kept stable for 3 to 5 seconds. The reading of displacement gauge 6 is recorded after it stabilizes to avoid data errors caused by instantaneous fluctuations. The tension force value corresponding to each stage of tensioning and the vertical displacement value of screw 1 collected by displacement gauge 6 are recorded simultaneously. Based on the estimated range of axial force of screw 1 obtained from previous bridge inspections, a graded tensioning scheme was formulated: the tensioning force is divided into several stages before reaching the estimated axial force of screw 1, and into several stages after reaching the estimated axial force; in this embodiment, when the vertical displacement of screw 1 begins to increase significantly (i.e., the tensioning force approaches or reaches the actual axial force T0 of screw 1), at least 4 stages of tensioning are added to obtain sufficient data for the T > T0 stage; Start jack 11 and gradually apply tension force according to the preset graded loads. After each load is applied, maintain a stable position for a few seconds. Once the displacement gauge 6 reading stabilizes, record the tension T of the current grade. i And the corresponding vertical displacement Δli of screw 1; During the tensioning process, the stress state of each component of the device is monitored in real time to ensure that the support angle 8 is not loose, the connector 12 is not deformed, and the displacement gauge 6 has good contact, so as to avoid abnormal situations affecting the accuracy of the data.

[0038] Based on the recorded tension force and vertical displacement values, the actual axial force of the screw is calculated using a function curve fitting algorithm. The core principle is based on the force characteristics of the tension rod and Hooke's law. The specific process is as follows: Force stage analysis: In this example, T is the tension of the jack (11 tensions), and T0 is the axial force of the cable clamp screw.

[0039] When T < T0, for the upper screw pair, when the jack is tensioned, the upper screw pair is like a tension rod under axial tension. According to the force characteristics of the tension rod, it will undergo longitudinal deformation, that is, the upper screw pair has vertical displacement. Optionally, according to Hooke's Law, the relationship between the tension Ti of the jack and the vertical displacement Δli of the upper screw is as shown in the following formula (1); (1) Where Δli represents the vertical displacement of the upper screw pair during the i-th stage of tensioning of jack 11, i = 1, 2, 3, … , N; Ti represents the tension force corresponding to the i-th stage of tensioning of jack 11; L1 represents the original length of the upper screw pair before tensioning; E represents the elastic modulus of screw 1; A represents the cross-sectional area of ​​screw 1; N represents the number of stages of tensioning of screw 1; Optionally, simplifying equation (1) yields: Δl i =k1T i (2) Where k1 is a constant, ; When T = T0, the upper screw pair is in a critical state, but equation (1) still applies. At this time, the relationship between the tension Ti of the jack and the vertical displacement Δli of the upper screw pair can be expressed as: Δl0=k1T0 (3) When T > T0, optionally, for the upper screw pair + middle screw (here both are defined as the upper and middle screws), when the jack 11 is tensioned, the upper and middle screws are also a tension rod under axial tension. According to the force characteristics of the tension rod, it will undergo longitudinal deformation, that is, the upper and middle screws have vertical displacement. Optionally, when T > T0, the vertical displacement of the upper screw is based on the Δl0 already generated in the upper screw pair. Therefore, according to Hooke's law, the relationship between the tension Ti of the jack and the vertical displacement Δli of the upper screw is as shown in the following formula (4). (4) i = N +1 Where L2 represents the initial length of the middle screw before tensioning of screw 1; i represents the i-th tensioning of screw 1, and i = 2, 3, … , N + 1; Optionally, equation (4) can be further simplified to: (5) in, Optionally, based on the force characteristics of the cable clamp screw during the tensioning process described above, it can be seen that during the tensioning process of screw 1, each tensioning force Ti of jack 11 has a corresponding vertical displacement Δli of screw 1. According to equations (2) and (5), the relationship between the tensioning force Ti of jack 11 and the vertical displacement Δli of screw 1 is expressed as a linear function equation. In order to measure the axial force T0 of screw, it is only necessary to solve for the intersection of these two functions. In the solution (Ti, Δli) of the intersection, Ti is the axial force T0 of screw.

[0040] The derivation of the intersection solution is shown below: Step 1: Make equation (2) equal to equation (5) k1Ti = k2Ti + β (6) Step 2: Substituting β = (k1 - k2)T0 into equation (6) yields k1Ti = k2Ti + (k1 - k2 )T0 (7) Step 3: According to equation (7), we can directly solve for... Ti=T0 (8) Based on the above derivation and solution process, it can be seen that during the tensioning process of the cable clamp rod, at different tensioning stages, the tension force Ti of jack 11 and the vertical displacement Δli of screw 1 satisfy a certain functional relationship. To measure the tension T0 of the cable clamp screw, it is only necessary to solve for the intersection point of the functional relationship line between the tension force Ti of jack 11 and the vertical displacement Δli of screw 1 at different tensioning stages. That is, Ti in the coordinates (Ti, Δli) of the intersection point of the two functional equations is the tension T0 of the cable clamp screw to be measured.

[0041] Optionally, when T ≤ T0, record the tension force Ti and the corresponding vertical displacement Δli value of the cable clamp screw during the 11-stage tensioning of the jack; when T > T0, record the tension force Ti and the corresponding vertical displacement Δli value of the cable clamp screw during the 11-stage tensioning of the jack; based on the recorded coordinate point values, use MATLAB software and curve fitting algorithm to fit two function equations respectively. In the displacement-tension force graph, the coordinates of the intersection point of the two function curves are (Ti, Δli). The horizontal coordinate Ti of the intersection point is the axial force of the cable clamp screw, and the vertical coordinate Δli is the vertical deformation displacement of the cable clamp screw under the 11-stage tension Ti of the jack.

[0042] In actual engineering, based on the axial force of bolt 1 obtained from the preliminary bridge inspection, the pre-tensioning load is divided into six levels before the tension force reaches the axial force of the cable clamp bolt, and another six levels after reaching the axial force. This is to record the tension force Ti of jack 11 and its corresponding vertical displacement Δli during the tensioning process of bolt 1. The displacement-tension force function equation for each stage is fitted based on each coordinate point, and the coordinates of the intersection point of the function equation are then solved to obtain the tension of the cable clamp bolt more accurately. The measured axial force of the bolt is compared with the design requirements to determine whether it needs to be tightened again. If the axial force is lower than 70% of the design axial force, it should be tightened promptly using a retightening device, and the force should be remeasured to ensure it returns to the design axial force. This method uses the coordinate points formed by the measured jack tension force Ti and its corresponding vertical displacement Δli, combined with a curve fitting algorithm, to obtain the displacement-tension force function equations for different stages, and calculates the coordinates of the intersection points of the function equations. This allows for accurate measurement of the tension of the cable clamp bolts in actual engineering projects; simultaneously, the axial force of bolts that does not meet the design requirements should be retightened promptly to ensure structural safety.

[0043] Figure 4 shows a schematic diagram for calculating the axial force of the cable clamp screw. Based on the recorded tension force-displacement coordinates, two function equations are fitted using a curve fitting algorithm in MATLAB software. The intersection point (Ti, Δli) of the two function equations is then solved. The vertical coordinate Δli of this intersection point represents the displacement of screw 1 when jack 11 is tensioned, and the horizontal coordinate Ti represents the axial force of the screw. Thus, the accurate axial force of the screw can be calculated.

[0044] In this embodiment, the operation of re-tightening and secondary testing is as follows: the actual axial force of the screw 1 is compared with the design axial force. If the actual axial force does not meet the design requirements, the screw 1 is tightened by rotating the nut 2 through the re-tightening rod 10 through the re-tightening hole 9 of the support angle 8 and cooperating with the nut sleeve 7. After tightening, perform the staged tensioning and record the data, fit the curve and solve the axial force again until the axial force of screw 1 is restored to the design axial force.

[0045] Specifically, the actual axial force of screw 1 is compared with the designed axial force, and a re-tightening operation and secondary inspection are performed based on the comparison results: Re-tightening judgment criteria: If the actual axial force of screw 1 is less than 70% of the design axial force, then screw 1 is determined to need to be re-tightened. Re-tightening operation: Keep the jack 11 in a tensioned state to offset part of the axial force of the screw 1. The re-tightening rod 10 passes through the re-tightening hole 9 of the support angle 8 and connects to the nut sleeve 7. Rotate the re-tightening rod 10 to drive the nut sleeve 7 and the screw 1 and nut 2 to rotate clockwise, and gradually tighten the screw 1. During the tightening process, observe the reading of the displacement gauge 6 in real time to avoid over-tightening and causing the axial force to exceed the design range. Secondary inspection: After tightening, loosen the load of jack 11 and reapply graded tension, repeat the previous steps, and measure the axial force of screw 1 again; if the measured axial force returns to the design axial force range, the re-tightening and curing is completed; if it still does not meet the standard, repeat the re-tightening operation and secondary inspection until the axial force of screw 1 meets the design requirements.

[0046] This embodiment, through the combination of the aforementioned device and method, achieves integrated high-precision detection and re-tightening of the screw 1's axial force: the measurement accuracy of the displacement gauge 6, combined with a curve fitting algorithm, ensures that the axial force measurement error is controlled within the allowable range; the graded tensioning and data recording process guarantees the accuracy of the force analysis; the re-tightening operation is highly targeted and can quickly restore the diminished axial force of the screw 1. The entire process does not require disassembly of the main structure of the cable clamp 3, constituting non-destructive testing and maintenance. Furthermore, the device components are detachable and reusable, and assembly and disassembly are convenient, effectively reducing the risks of high-altitude operations and maintenance costs, and providing a reliable guarantee for the safe operation of the suspension bridge.

[0047] It should be noted that, for the sake of simplicity, the foregoing method embodiments are all described as a series of actions. However, those skilled in the art should understand that this application is not limited to the described order of actions, as some steps may be performed in other orders or simultaneously according to this application. Furthermore, those skilled in the art should also understand that the embodiments described in the specification are preferred embodiments, and the actions and modules involved are not necessarily essential to this application.

[0048] In the above embodiments, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.

[0049] In the several embodiments provided in this application, it should be understood that the disclosed apparatus can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces; the indirect coupling or communication connection between devices or units may be electrical or other forms.

[0050] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0051] Furthermore, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software program module.

[0052] The embodiments of this application have been described in detail above. Specific examples have been used to illustrate the principles and implementation methods of this application. The description of the above embodiments is only for the purpose of helping to understand the method and core ideas of this application. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of this application. Therefore, the content of this specification should not be construed as a limitation of this application.

Claims

1. An integrated device for detecting and re-tightening the axial force of suspension bridge cable clamp bolts, characterized in that, include: Support bracket, nut sleeve, jack, connector, re-tightening rod, displacement gauge, displacement gauge bracket and magnet; The support angle cooperates with the cable clamp to provide a foundation for overall assembly. The connector cooperates with the screw and is used to connect the screw and the jack. The jack applies a tensioning force to the screw based on the support angle. The displacement gauge is fixed to the cable clamp by a magnet and is used to detect the displacement information of the screw during the tensioning process. The nut sleeve is adapted to the nut of the screw. The re-tightening rod can pass through the support angle and cooperates with the nut sleeve to achieve screw fastening.

2. The integrated device for detecting and re-tightening the axial force of suspension bridge cable clamp screws according to claim 1, characterized in that, The support angle is detachably connected to the cable clamp, and the support angle is provided with a re-tightening hole for the re-tightening rod to pass through. The jack is mounted between the support angle and the connecting piece.

3. The integrated device for detecting and re-tightening the axial force of suspension bridge cable clamp screws according to claim 1, characterized in that, The displacement gauge bracket is connected to a magnet, the displacement gauge is mounted on the displacement gauge bracket, and the detection end of the displacement gauge is in contact with the connector.

4. The integrated device for detecting and re-tightening the axial force of suspension bridge cable clamp screws according to claim 1, characterized in that, The nut sleeve is fitted onto the outside of the nut on the screw, and the re-tightening rod passes through the re-tightening hole of the support angle and connects to the nut sleeve.

5. The integrated device for detecting and re-tightening the axial force of suspension bridge cable clamp screws according to claim 1, characterized in that, The connector is connected to the end of the screw away from the cable clamp via an internal thread. One end of the connector abuts against the jack, and the other end corresponds to the detection end of the displacement gauge.

6. A method for detecting and re-tightening the axial force of cable clamp bolts in suspension bridges, characterized in that... The integrated device for detecting and re-tightening the axial force of suspension bridge cable clamp bolts according to any one of claims 1 to 5 includes: The screw axial force is tested and tightened to meet the standard by assembling the device components, calibrating the displacement gauge, performing graded tensioning and recording data, fitting the curve to solve the axial force, re-tightening and secondary testing.

7. The method for detecting and re-tightening the axial force of the cable clamp bolt of a suspension bridge according to claim 6, characterized in that, The operation of the assembly device components is as follows: the support bracket, nut sleeve, jack, connector, re-tightening rod, displacement gauge, displacement gauge bracket and magnet are respectively assembled on the cable clamp and screw rod, so that the support bracket is connected to the cable clamp, the connector is threadedly connected to the screw rod, the jack is clamped between the support bracket and the connector, the displacement gauge is fixed to the cable clamp through the displacement gauge bracket and magnet, and the detection end of the displacement gauge is in contact with the connector, and the re-tightening rod can pass through the re-tightening hole of the support bracket and cooperate with the nut sleeve.

8. The method for detecting and re-tightening the axial force of the cable clamp bolt of a suspension bridge according to claim 6, characterized in that, The operation of calibrating the displacement gauge is as follows: after placing the displacement gauge at the corresponding position on the top of the connector, the displacement gauge is calibrated and adjusted.

9. The method for detecting and re-tightening the axial force of the cable clamp bolt of a suspension bridge according to claim 6, characterized in that, The operation of graded tensioning and data recording is as follows: the screw is tensioned in stages using a jack, and the tension force value corresponding to each stage of tensioning and the vertical displacement value of the screw collected by the displacement gauge are recorded simultaneously. The operation of solving the axial force by fitting the curve is as follows: based on the recorded tension force and vertical displacement values, a screw displacement-tension force curve is fitted, and the actual axial force of the screw is obtained by calculating the coordinate values ​​of the intersection point of the two curves at different tension stages.

10. The method for detecting and re-tightening the axial force of the cable clamp bolt of a suspension bridge according to claim 6, characterized in that, The re-tightening and secondary inspection operation is as follows: compare the actual axial force of the screw with the design axial force. If the actual axial force does not meet the design requirements, the screw is tightened by rotating the nut sleeve through the re-tightening rod passing through the re-tightening hole of the support angle. After tightening, perform staged tensioning again, record the data, and fit the curve to solve for the axial force until the screw axial force is restored to the design axial force.

Images