Construction method of multi-strand steel strand cable vibration control system

Abstract

The application discloses a construction method of a multi-strand steel strand buckle cable vibration control system and belongs to the technical field of bridge and structure engineering. The method comprises the following steps: setting a mark at a preset position of a single steel strand; lifting the steel strand; when the mark passes through a lower anchoring position, sleeving a sleeve pipe on the mark position and fixing the sleeve pipe; continuously lifting and repeatedly sleeving at a next mark position until all the preset positions are provided with the sleeve pipes; and uniformly tensioning all the steel strands to form buckle cables. The preset positions are determined based on modal analysis of the buckle cables and are located at amplitude peak values of each order modal vibration mode. The sleeve pipe is a C-shaped high-damping rubber pipe which is fixed on the steel strand through radial clamping of a binding belt. The method integrates the sleeve pipe installation into the hanging cable lifting process, does not need high-altitude operation, can effectively inhibit multi-order modal vibration of the buckle cables and eliminate collision noise between the steel strands, and is safe, economical and efficient in construction.

Description

Technical Field

[0001] This invention relates to the field of bridge and structural engineering technology, specifically to a construction method for a multi-strand steel strand cable vibration control system. Background Technology

[0002] The cable-stayed bridge construction method is one of the most widely used methods for arch bridge construction. It is widely applicable, highly safe, and has simple construction procedures, holding an important position in the field of arch bridge construction technology. First proposed by a French engineer in 1952, the cable-stayed bridge construction method was subsequently adopted by engineers worldwide for arch bridge construction. my country began using this method for the construction of large-span reinforced concrete arch bridges in the 1970s. For example, the Mamingxi Bridge with a main span of 150m was completed in 1979; subsequently, the Tianchi Bridge with a main span of 205m was completed in 2007, and the Mupeng Grand Bridge with a main span of 165m was successfully closed in 2012. As the cable-stayed bridge construction method has matured, its application has become even more widespread.

[0003] As the span of the arch bridge increases, the height of the anchor tower and the length of the anchor cable also increase accordingly. This leads to a decrease in the lateral stiffness, natural frequency, and structural damping of the anchor cable, making it prone to significant fluttering under pulsating winds. Furthermore, the anchor cable is generally composed of multiple steel strands without a sheath. Because the anchor cable is a temporary structure, its cross-section is formed by multiple strands of steel wire rather than a circular cross-section, resulting in poor aerodynamic stability and various vibrations under normal wind conditions. In addition, the vibration of the tall anchor tower can also cause parametric vibrations in the anchor cable. Moreover, due to uneven tension of the anchor cable strands, different windward characteristics of each strand, and small spacing between strands, there is a phenomenon of the strands slapping against each other under low wind speeds. This slapping noise is loud, causing significant psychological stress for construction workers and posing a risk of long-term vibration fatigue fracture of the strands.

[0004] The aforementioned vibration problems of construction cables for arch bridges urgently require corresponding vibration reduction measures. However, existing vibration control technologies for cable structures are mainly developed for the stay cables of cable-stayed bridges, suspension bridges, and suspenders of suspension bridges. For these main structural components, pneumatic measures, structural measures, and dampers are primarily employed. Pneumatic measures mainly involve altering the aerodynamic shape by wrapping helical lines around the cable sheath to reduce aerodynamic excitation loads and thus reduce vibration. Structural measures include using auxiliary cables to connect adjacent cables and increase the frequency, thereby reducing vibration. Dampers primarily involve using lateral dampers supported by brackets or sleeves to directly dissipate energy and suppress the vibration of stay cables. Due to the special form of construction cables, the above-mentioned vibration reduction measures for cables / suspenders are not applicable. First, the multiple strands of the cable have no external sheath, making it impossible to implement pneumatic measures. Furthermore, the lack of external sheath constraint on the multiple strands causes them to vibrate independently, and the cable-end dampers and auxiliary cables are designed for the overall movement of the cable body, failing to effectively suppress the vibration of individual strands.

[0005] Vibration control of the cables in the construction towers of arch bridges has always been a challenge in the field. Vibration-induced fatigue poses a threat to construction safety, and the slapping sound of the cable strands has long caused anxiety and distress to on-site construction workers. Existing vibration reduction measures for permanent bridge cable components are not suitable for construction cables, and there is a lack of efficient and applicable vibration reduction and control technology for multi-strand steel strand cables. Summary of the Invention

[0006] The purpose of this invention is to overcome the shortcomings of the above-mentioned background technology and provide a construction method for a multi-strand steel strand cable vibration control system.

[0007] The technical solution of this invention is: a construction method for a multi-strand steel strand cable vibration control system, wherein the multi-strand steel strand cable vibration control system includes multiple steel strands and anchors for fixing the two ends of the steel strands, the multiple steel strands are used for tensioning to form a cable, and the construction method includes: S1. Set a mark at the preset position of the single steel strand to identify the installation sleeve; S2. Lift a single steel strand. After the marked position on the steel strand passes the lower anchor position, stop lifting and put the sleeve on the marked position of the steel strand. S3. Fix the sleeve to the steel strand; S4. Continue to lift the steel strand, and after passing the lower anchor position at the next marked position, pause the lifting and repeat steps S2 and S3 to install the sleeve at the marked position until all preset positions on the steel strand are equipped with sleeves. S5. After all the steel strands and their sleeves are installed and lifted into place, all the steel strands are then tensioned and fixed in a unified manner using anchors to form a complete cable. Perform steps S1 to S5 for each steel strand used to form the buckle to complete the installation of all steel strands and their sleeves.

[0008] According to the construction method of a multi-strand steel strand cable vibration control system provided by the present invention, in step S1, the preset position is the amplitude peak position of each mode shape determined based on the modal analysis of the cable.

[0009] According to the construction method of the vibration control system of multi-strand steel strand cable provided by the present invention, the preset position includes at least the midpoint position in the length direction of the steel strand, as well as the quarter-length position and the three-quarter-length position, to correspond to the amplitude peaks of the first-order mode and the second-order mode of the cable, respectively.

[0010] According to the construction method of a multi-strand steel strand cable vibration control system provided by the present invention, in step S2, the sleeve is a C-shaped tube with an opening along its axial direction, so as to be fitted from the radial side of the steel strand.

[0011] According to the construction method of the multi-strand steel strand cable vibration control system provided by the present invention, in step S3, a binding tape is used to wrap around the outer periphery of the sleeve to radially shrink the sleeve and clamp it to the steel strand.

[0012] According to the construction method of the multi-strand steel strand cable vibration control system provided by the present invention, multiple binding straps are used to wrap around the outer circumference of the sleeve. The multiple binding straps are evenly spaced along the axial direction of the sleeve to radially shrink the sleeve and clamp it to the steel strand.

[0013] According to the construction method of the multi-strand steel strand cable vibration control system provided by the present invention, in step S1, a mark is formed on the surface of the steel strand by spraying.

[0014] According to the construction method of the multi-strand steel strand cable vibration control system provided by the present invention, in step S2, after passing the lower anchor position at the marked position, the lifting is paused, and then the sleeve is installed and fixed.

[0015] According to the construction method of the multi-strand steel strand cable vibration control system provided by the present invention, the multi-strand steel strand cable vibration control system further includes a traction cable, and in step S2, the traction cable is connected to the steel strand and lifted.

[0016] According to the present invention, a construction method for a multi-strand steel strand cable vibration control system is provided, wherein the sleeve is made of high-damping rubber material and is used to dissipate vibration energy through its own viscoelastic deformation when adjacent steel strands vibrate relative to each other.

[0017] The advantages of this invention are: 1. Precise vibration reduction at fixed points, significantly improving the effectiveness of multimodal vibration control. The construction method of this invention is based on cable modal analysis, which pre-marks the installation at the peak amplitude position (such as the midpoint or quarter point), so that the vibration damping sleeve is precisely positioned at the maximum amplitude of the multi-mode vibration of the steel strand. Compared with indiscriminate global layout or random installation, this fixed-point installation strategy can achieve maximum vibration energy dissipation with the fewest number of devices, and has excellent synergistic suppression effect on first-order, second-order and other multi-order vibrations.

[0018] 2. Effectively separates steel strands, eliminates steel-to-steel collisions, and reduces abnormal noise in the working environment. The construction method of this invention involves circumferentially clamping and fixing C-shaped sleeves or sleeves made of high-damping rubber at predetermined positions on each steel strand. These sleeves form a physical isolation barrier between adjacent steel strands. This separation effect directly prevents rigid collisions between steel strands under wind or construction loads, fundamentally eliminating impact noise and significantly improving the working acoustic environment during construction and operation.

[0019] 3. Ground pre-assembly and subsequent lifting into position completely avoid high-altitude operations, ensuring safe and economical construction. The construction method of this invention defines a ground or low-level installation mode: lifting is immediately paused after the marked position passes the lower anchoring zone for sleeve installation and fixation; subsequently, the sleeve is simultaneously lifted with the steel strand to a preset high-altitude position. This method concentrates all sleeve installation work in the easily accessible lower area, eliminating the need for erecting high-altitude work platforms or high-altitude climbing installation, greatly reducing construction risks and costs, and demonstrating outstanding construction convenience and economy.

[0020] 4. Discontinuous local installation saves materials and facilitates maintenance. The construction method of this invention limits the installation of sleeves only at each preset marked position (local position), rather than wrapping the entire length of the steel strand. By using evenly spaced binding straps for fixation, this discrete vibration reduction and separation design significantly reduces the amount of high-damping material used and lightens the added weight of the ties while ensuring functional requirements are met. It also facilitates subsequent visual inspection and local maintenance of the main body of the steel strand.

[0021] 5. Non-destructive clamping and easy installation structure ensures long-term reliable service. The construction method of this invention specifies that the sleeve adopts an axially open C-shaped tube and is fixed by axially and evenly spaced binding straps, realizing direct fitting and radial contraction clamping from the radial side of the steel strand. This method avoids damaging connections such as welding and perforation on the stressed steel strand, protecting the strength of the steel strand matrix; at the same time, the installation of the open tube and binding straps is extremely convenient, and it can provide reliable long-term clamping force through uniform constraint, ensuring that the sleeve does not slip or loosen under long-term vibration environment at high altitudes. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the cable tensioning structure of the present invention; Figure 2 This is a schematic diagram of the steel strand and sleeve installation structure of the present invention; Figure 3 This is a schematic diagram of the steel strand tensioning and installation of the present invention; Figure 4 This is a schematic diagram comparing the vibration of the present invention with and without a sleeve installed at the end of the buckle (controlled vibration) and vibration without a sleeve installed (uncontrolled vibration). Figure 5 This is a schematic diagram comparing the vibration of the present invention with and without a sleeve installed at the quarter point of the buckle (controlled vibration) and vibration without a sleeve installed (uncontrolled vibration). Figure 6 This is a schematic diagram comparing the vibration of the present invention with and without a sleeve installed at the bifurcation point of the buckle (controlled vibration).

[0023] Among them: 1-steel strand; 2-sleeve; 3-binding strap; 4-anchor; 5-clip rope; 6-traction rope. Detailed Implementation

[0024] Embodiments of the present invention are described in detail below, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0025] In the description of this invention, it should be understood that the terms "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0026] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0027] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0028] This invention discloses a construction method for a multi-strand steel strand cable vibration control system. The core of this method lies in the deep integration of the installation of vibration-damping sleeves with the cable hanging and lifting process. Before construction, modal analysis is used to determine the peak amplitude positions of each vibration mode of the cable, and markings are sprayed onto the steel strands. During lifting, the process pauses after the markings pass the lower anchoring position. At low altitude, a C-shaped sleeve with an axial opening made of high-damping rubber is radially inserted and fitted onto the marking. Multiple binding straps are then evenly and spaced along the axial direction of the sleeve, causing it to contract radially and clamp and fix. Lifting continues, and the process is repeated until all sleeves reach the preset high-altitude positions synchronously with the steel strands, ultimately achieving uniform tensioning and shaping. This method transforms high-altitude installation work into ground or low-altitude work, significantly improving construction safety and economy. Simultaneously, the precise placement of the sleeves achieves efficient dissipation of multi-modal vibrations and also functions to separate the steel strands and eliminate abnormal noise from steel-to-steel collisions.

[0029] Specifically, such as Figures 1-3As shown, the multi-strand steel strand cable vibration control system of the present invention includes multiple steel strands for forming the cable and anchors for fixing the two ends of the steel strands. The construction method of the present invention includes the following steps: S1. After the single steel strand 1 used to form the buckle 5 is manufactured or cut, multiple preset positions are measured and marked on its surface according to the design drawings, and clear and visible marks are set at the positions using a marker pen or similar tool to mark the parts where the sleeve 2 needs to be installed later.

[0030] S2. Reliably connect the traction cable 6 to the front end of the steel strand 1, start the hoist or other lifting equipment, and lift the single steel strand 1 through the traction cable 6. During the lifting process, the steel strand 1 gradually passes through the reserved hole of the lower anchor 4. When the first marked position just passes through the lower anchoring position (i.e., the cable entry port of the anchor 4), the operator pauses the lifting and radially fits a vibration damping sleeve 2 onto the steel strand 1 at the marked position.

[0031] S3. Secure the sleeve 2 to the steel strand 1 with fasteners or bindings to prevent axial slippage during subsequent lifting and vibration.

[0032] S4. Continue to lift the steel strand 1. After the next marked position passes the lower anchor position, pause the lifting and repeat the installation and fixing operation until the sleeve 2 has been installed and fixed at all the preset marked positions on the steel strand 1.

[0033] S5. Perform steps S1 to S4 above on each steel strand 1 used to form the buckle 5. After all the steel strands 1 and their sleeves 2 are lifted to the design position, use the anchors 4 at both ends to tension and lock all the steel strands 1 in a unified manner to form a complete buckle 5 with multiple steel strands 1 and built-in vibration damping sleeves 2.

[0034] This invention organically integrates the erection process of the cable 5 with the installation process of the vibration-damping sleeve 2. Traditional methods require personnel to climb to various pre-set points at high altitudes after the cable 5 is tensioned, posing a significant construction risk. This invention takes the opposite approach, utilizing the construction characteristic of the steel strand 1 being inserted segment by segment from the lower anchor point. The installation is timed to occur in a low-altitude area just after the marked position has passed the lower anchor point. At this point, the pre-set points are exposed within the reach of personnel on the ground or near the bridge deck. After securing the sleeve, the sleeve 2 is carried to the target high-altitude position as the steel strand 1 continues to rise. Thus, high-altitude operations are transformed into ground or low-altitude operations, completely changing the construction process.

[0035] The construction method provided in this embodiment offers outstanding construction safety and economy. The installation of the vibration-damping sleeve 2 is concentrated entirely in the easily accessible lower area, eliminating the need for high-altitude work platforms or climbing, thus greatly reducing construction risks and labor intensity. Furthermore, the piece-by-piece, point-by-point installation method ensures a controllable and orderly construction process, without interfering with the overall tensioning and forming process of the buckle 5. The solution is simple, convenient, and cost-effective.

[0036] In some embodiments of the present invention, this embodiment defines the method for determining the preset position in step S1, that is, determining the peak position of each order amplitude as the installation point through modal analysis.

[0037] Before performing step S1, a finite element model of the cable 5 to be constructed is first established. This model is parameterized based on the design length, cross-sectional area, mass per unit length, design force, and boundary conditions at both ends (usually simplified to hinged or fixed supports). Modal analysis is then performed based on this model to determine the natural frequencies and corresponding mode shapes of the cable 5.

[0038] The specific algorithm is as follows: Input: Cable length L, cable force T, mass per unit length m, bending stiffness EI (if not negligible), boundary conditions.

[0039] For a taut flexible cable, its vibration equation can be simplified to a string vibration model, with the nth natural frequency... mode shape function , where x is the distance from the lower anchor point along the cable length direction.

[0040] When bending stiffness needs to be considered, a beam model is used for finite element eigenvalue analysis. The discrete cable is divided into several beam elements, and the overall stiffness and mass matrices are assembled to solve the generalized eigenvalue problem. This yields the frequencies ω and corresponding displacement mode vectors φ for each order.

[0041] Extract the mode shape vectors of the first few modes (e.g., the first three modes) and calculate the absolute values ​​of the displacement amplitudes at each node. The peak amplitude of the first mode occurs at x = L / 2 (midpoint); the peak amplitude of the second mode occurs at x = L / 4 and x = 3L / 4 (one-quarter and three-quarters points); the peak amplitude of the third mode occurs at L / 6, L / 2, and 5L / 6, and so on.

[0042] Based on the required modal order (usually including at least the first two), select the peak points of the aforementioned vibration modes as preset locations, and export the distance data from these locations to the lower anchor point. During construction, use a steel ruler to measure the corresponding distances on steel strand 1 and set marks at those locations.

[0043] The vibration damping sleeve 2 dissipates vibration energy through the viscoelastic deformation of the high-damping material, and its energy dissipation efficiency is directly related to the vibration displacement amplitude at the installation location. In modal vibration, the position with the largest amplitude is located at the antinode of the vibration mode, where the vibration velocity and deformation are the greatest, and the sleeve 2 can generate the greatest damping force and energy dissipation. Therefore, by precisely arranging the sleeve 2 at the peak points of each vibration mode, the optimal multimodal vibration reduction effect can be achieved with the fewest number of devices. This invention cleverly utilizes known parameters such as cable force and length that can be obtained before construction, and predicts the peak points through theoretical analysis or numerical calculation, making the construction markings traceable.

[0044] This embodiment achieves precise, fixed-point vibration reduction, significantly improving the control efficiency of multimodal vibration. By accurately calculating and marking the midpoint, quarter points, and other positions, the vibration damping sleeve 2 is precisely positioned at the maximum amplitude of the first and second modes, simultaneously suppressing multiple vibrations. The vibration reduction efficiency is far superior to uniform or random installation. Furthermore, this mode-based discrete arrangement strategy avoids full-length wrapping, significantly reducing the amount of high-damping material used and decreasing the additional weight of the buckle 5, resulting in excellent economic efficiency.

[0045] In other embodiments of the present invention, this embodiment defines the opening structure and high-damping material composition of the sleeve 2, such as... Figure 2 As shown.

[0046] A C-shaped sleeve 2 with an opening along its entire axial length is manufactured using high-damping rubber material through molding or extrusion. The length of the sleeve 2 is determined based on the required damping force and separation requirements, generally 5 to 15 times the diameter of the steel strand 1. The circumferential angle of the C-shaped opening is designed to be 40° to 80°, so that the gap at the opening is slightly larger than the diameter of the steel strand 1, facilitating radial insertion. In step S2, after the marked position is anchored at the lower end, the operator holds the C-shaped sleeve 2 and aligns its opening with the steel strand 1 from the radial side, gently pushing it to allow the steel strand 1 to enter the inner hole of the sleeve 2, completing the fitting. After fitting, the sleeve 2 naturally encircles the steel strand 1, but due to elasticity, there may be a slight opening, which is closed by external clamping in step S3.

[0047] The use of an axially open C-shaped tube avoids the cumbersome process of inserting the traditional closed tube from the end of the steel strand 1, making it particularly suitable for situations where the ends of the steel strand 1 are already connected to the traction cable 6 or have anchor heads. Under alternating stress, the high-damping rubber material exhibits a full stress-strain hysteresis curve, with a loss factor exceeding 0.3. When the cable 5 experiences wind-induced or construction load-induced vibrations, relative motion occurs between adjacent steel strands 1. The sleeve 2 undergoes shear or tensile deformation under the compression and friction of the steel strands 1, utilizing the viscoelastic effect of the rubber material to convert the vibrational mechanical energy into heat energy for dissipation. Simultaneously, the sleeve 2 physically separates adjacent steel strands 1, preventing direct steel-to-steel collisions.

[0048] This embodiment combines vibration reduction and separation functions, and enables convenient installation. The C-shaped opening structure allows for a single radial push-in action during installation, resulting in extremely fast installation speed, making it particularly suitable for construction rhythms involving point-by-point and strand-by-strand installation. The high-damping rubber sleeve 2 not only efficiently dissipates vibration energy through viscoelastic deformation, but its inherent flexibility and damping characteristics also buffer potential contact between steel strands, fundamentally eliminating abnormal noises from metal-on-metal collisions, effectively improving the working environment during construction and operation, and protecting the anti-corrosion layer on the surface of the steel strand 1 from damage.

[0049] In a further embodiment of the present invention, this embodiment specifies a particular method of fixing the sleeve 2 by uniformly and spacedly wrapping multiple binding straps 3 along the axial direction, such as... Figure 2 and 3 As shown.

[0050] In step S3, after the C-shaped sleeve 2 is fitted onto the marked position of the steel strand 1, a weather-resistant self-locking nylon cable tie or stainless steel cable tie is used as a binding strap 3. Starting from one end of the sleeve 2, the binding strap 3 is wrapped around the outer circumference of the sleeve 2 and tightened until the C-shaped opening is completely closed, and the inner wall of the sleeve 2 is tightly attached to the surface of the steel strand 1, generating sufficient radial pressure. Then, the next strand is bound sequentially along the axial direction of the sleeve 2 at uniform intervals (e.g., every 2-3 cm), until multiple binding straps 3 are arranged along the entire length of the sleeve 2. After all the binding straps 3 are bound, the circumferential and axial positions of the sleeve 2 are checked to ensure there is no looseness or slippage, and the fixing operation is completed.

[0051] The binding straps 3 provide a uniform and continuous radial contraction force. When multiple binding straps 3 are evenly spaced along the axial direction of the sleeve 2, they can prevent arching deformation caused by single-point constraint in the middle of the sleeve 2, ensuring uniform contact between the entire inner surface of the sleeve 2 and the steel strand 1, thus guaranteeing the uniformity of friction and damping effect. At the same time, the redundant design of segmented multi-constraints ensures that even if one binding strap 3 accidentally comes loose under long-term vibration, the remaining binding straps 3 can still maintain the positional stability of the sleeve 2, improving the reliability and durability of the system.

[0052] This embodiment achieves non-destructive clamping and fixing, ensuring reliability for long-term service. The installation of the binding straps 3 eliminates the need for welding, drilling, or other methods that could damage the high-strength steel strand 1 substrate, thus protecting the mechanical properties of the steel strand 1. The evenly spaced multiple binding straps 3 provide stable radial restraint, ensuring that the sleeve 2 does not slip or loosen under the lifting of the steel strand 1 and long-term wind vibration. Moreover, the installation operation is extremely simple and quick, requiring only manual tightening, and the construction tools are lightweight and extremely low in cost.

[0053] In a preferred embodiment of the present invention, this embodiment defines the specific setting method of the marker in step S1.

[0054] In step S1, the steel strand 1 is laid flat on the construction site beforehand. Based on the preset position distance data calculated in Example 2, a measuring tape is used to measure and position the steel strand 1. Then, the operator holds a spray paint can, aligns it with the positioning point, and sprays a ring or a crosshair of brightly colored paint onto the surface of the steel strand 1, forming a ring or line mark. After the paint film dries, the next lifting operation can proceed. The paint used should be a type with high color contrast to the surface of the steel strand 1, strong adhesion, and fast drying.

[0055] During the continuous lifting of steel strand 1, operators need to quickly and accurately identify the preset position. The spray-painted markings are clearer and more durable than hand-drawn marks or stickers, and are not easily erased when the steel strand 1 passes the guide rollers or experiences slight friction. The bright color markings have extremely high visual recognition, ensuring that operators can instantly identify and time the lower anchoring position while the steel strand 1 is moving, achieving precise pausing and assembly.

[0056] The spray-painting method for marking is highly efficient, produces clear and durable marks, and ensures accurate positioning of the preset locations. Its ease of use lowers the technical barrier for construction workers, further enhancing the feasibility and reliability of the entire construction method.

[0057] In some embodiments of the present invention, this embodiment defines a step of pausing the promotion after the mark has passed before resuming the operation.

[0058] In step S2, the hoisting equipment operator and the lower-level installation operator coordinate closely via wireless intercom or pre-defined hand gestures. When the lower-level operator observes that the painted mark on the steel strand 1 is about to reach the lower anchoring port, a deceleration command is issued; when the mark has just passed the anchoring port by a predetermined distance (e.g., 10-20 cm), a stop command is immediately issued, and the hoisting equipment locks, achieving a smooth stop. In this stationary state, the installation personnel then perform the radial fitting of the sleeve 2 and the subsequent binding and fixing operations in step S3. After confirming that the installation is qualified, a command to continue hoisting is issued.

[0059] Direct installation during dynamic lifting is prone to positioning deviations and insecure installation, and poses a safety hazard of being scratched by the moving steel strand 1. Pausing the lifting completely stops the relative movement, transforming the dynamic process into a static installation procedure, providing operators with an undisturbed working window, and ensuring millimeter-level accuracy and reliable fixation of the sleeve 2 installation position.

[0060] This embodiment decouples the lifting and installation actions through a clearly defined pause and restart process, fully ensuring installation accuracy and construction safety. This makes it possible to precisely install the vibration damping sleeve 2 at the preset peak point, thus improving the installation accuracy of the sleeve 2.

[0061] In other embodiments of the invention, this embodiment defines an implementation in which the steel strand 1 is lifted using a traction cable 6.

[0062] like Figure 3 As shown, during the preparation stage of the construction of the cable 5, a high-strength traction steel wire rope (i.e., traction cable 6) is pre-passed through the cable holes of the lower anchor 4 and the upper anchor 4, and led out from the lower end. The lower end of the traction cable 6 is firmly connected to the front end of the steel strand 1 to be installed through a special clamp-type connector or a compression anchor head. The winch placed at the upper anchor 4 is started to wind up the traction cable 6, thereby pulling the steel strand 1 one by one through the holes of the anchor 4 from bottom to top, completing the lifting process.

[0063] In the construction of the multi-strand steel strand cable 5, the method of first laying the traction cable 6 and then pulling the steel strand 1 is a mature and efficient process. Its advantage lies in the ability to place the large and heavy power unit on the upper platform, while the lower end only needs to handle the connection and assembly operations, resulting in a clear division of labor and smooth construction flow. This invention integrates the installation of the sleeve 2 into this cable-hanging process, making it highly compatible with existing processes.

[0064] The use of traction cable 6 for lifting ensures smooth and controllable movement of the steel strand 1, providing excellent conditions for observation marking at the lower end, execution of pauses, and installation. This method eliminates the need for additional lifting equipment, directly utilizing the existing cable system, offering good economic efficiency, and effectively ensuring that each steel strand 1 and its sleeve 2 are delivered to the designed high-altitude position in sequence and accurately.

[0065] Specifically, the construction method of the multi-strand steel strand cable 5 vibration control system of the present invention can be carried out according to the following steps: (1) In the design stage, based on the design length and cable force of the 5-cable, the finite element modal analysis algorithm of the string vibration or beam model described in the above embodiment is used to solve the first two or three vibration modes and extract the distance from the peak amplitude of each mode to the lower anchor point, such as the midpoint (L / 2), quarter point (L / 4, 3L / 4), etc., as the preset installation position.

[0066] (2) Material preparation: Prepare several axially open C-shaped tubes made of high-damping rubber, and prepare enough self-locking weather-resistant binding tape 3.

[0067] (3) After the steel strand 1 is cut, it is laid flat on the ground. According to the marking method described above, the preset distance is measured with a tape measure, and a conspicuous mark is sprayed on each peak point with spray paint.

[0068] (4) Cable installation begins. Reliably connect the traction cable 6 to the front end of the first marked steel strand 1. Start the winch and begin lifting the steel strand 1 via the traction cable 6.

[0069] (5) Execute the pause control procedure: The person in charge of the lower construction closely observes the movement of the markers. When the first marker (e.g., at L / 4) passes the lower anchoring port, immediately order the pausing of lifting.

[0070] (6) During the paused static window, the operator takes a C-shaped sleeve 2, inserts its opening into the steel strand 1 from the radial side, and moves it to the position that just covers the sprayed mark. Then, take a binding strap 3 and wrap multiple straps evenly at intervals (e.g., 3cm intervals) along the axial direction of the sleeve 2, tightening them one by one to close the C-shaped tube and secure the steel strand 1 circumferentially.

[0071] (7) Notify the lifting operator to continue lifting, repeat steps (5) and (6), and install and fix the sleeve 2 at the remaining marked positions such as L / 2, 3L / 4 in sequence.

[0072] (8) After all the sleeves 2 of the steel strand 1 are installed, it is continuously lifted to the design position and temporarily anchored.

[0073] (9) Repeat steps (4) to (8) one by one for the remaining steel strands 1 used to form the buckle 5. During this process, the sleeves 2 of each steel strand 1 are installed at staggered heights, which can form a three-dimensional separation network between adjacent steel strands.

[0074] (10) After all the steel strands 1 and sleeves 2 are lifted into place, the anchors 4 at both ends are tensioned in a unified grade according to the design sequence, and the anchor heads are locked, thus forming a complete cable system with multiple internal high-damping vibration-damping separator sleeves 2.

[0075] like Figure 4 , 5 As shown in Figure 6, the present invention installed sleeves at the end, quarter point, and half point of the buckle for testing. The vibration of the buckle with sleeves installed (controlled) and without sleeves installed (uncontrolled) were compared. By comparing the vibration amplitude of the corresponding steel strands, it can be seen that the maximum vibration reduction position reduces the vibration displacement amplitude from about 10mm to less than 2mm, and the vibration reduction control effect is obvious.

[0076] This invention's construction method organically integrates several technologies, including modal analysis-guided point vibration reduction, low-altitude follow-up installation, convenient assembly and non-destructive binding of C-type high-damping rubber sleeves, clear spray-painted markings for identification, and precise pause control, forming a novel cable-stayed vibration reduction construction system. This system not only completely eliminates the risks of high-altitude operations during construction, achieving economic efficiency, but also, after bridge completion, utilizes the vibration-damping sleeves at the antinodes of various cable modes to maximally dissipate wind / rain vibration energy through viscoelastic damping, while physically isolating the collision paths of the steel strands and eliminating abnormal noise. The entire solution demonstrates outstanding safety, economy, and vibration and noise reduction effects, possessing significant value for widespread application.

[0077] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of this invention is defined by the appended claims and their equivalents.

Claims

1. A construction method for a multi-strand steel strand cable vibration control system, the multi-strand steel strand cable vibration control system comprising multiple steel strands (1) and anchors (4) for fixing the two ends of the steel strands (1), the multiple steel strands (1) being used for tensioning to form a cable (5), characterized in that, The construction method includes: S1. Set a mark at a preset position of the single steel strand (1) to identify the installation sleeve (2); S2. Lift a single steel strand (1). After the marked position on the steel strand (1) passes the lower anchor position, stop lifting and put the sleeve (2) on the marked position of the steel strand (1). S3, fix the sleeve (2) to the steel strand (1); S4. Continue to lift the steel strand (1), and after passing the lower anchor position at the next marked position, pause the lifting and repeat steps S2 and S3 to install the sleeve (2) at the marked position until all preset positions on the steel strand (1) are equipped with sleeves (2). S5. After all the steel strands (1) and their sleeves (2) are installed and lifted into place, all the steel strands (1) are tensioned and fixed in a unified manner by anchors (4) to form a complete cable (5). Steps S1 to S5 are performed on each steel strand (1) used to form the buckle (5) to complete the installation of all steel strands (1) and the sleeves (2) on them.

2. The construction method of a multi-strand steel strand cable vibration control system according to claim 1, characterized in that, In step S1, the preset position is the amplitude peak position of each mode shape determined by modal analysis based on the clasp (5).

3. The construction method of a multi-strand steel strand cable vibration control system according to claim 2, characterized in that, The preset positions include at least the midpoint position along the length of the steel strand (1), as well as the quarter-length position and the three-quarter-length position, to correspond to the amplitude peaks of the first-order mode and the second-order mode of the cable (5), respectively.

4. The construction method of a multi-strand steel strand cable vibration control system according to claim 1, characterized in that, In step S2, the sleeve (2) is a C-shaped tube with an opening along its axial direction so as to be fitted from the radial side of the steel strand (1).

5. A construction method for a multi-strand steel strand cable vibration control system according to claim 1 or 4, characterized in that, In step S3, a binding strap (3) is used to wrap around the outer periphery of the sleeve (2) to radially shrink the sleeve (2) and clamp it to the steel strand (1).

6. The construction method of a multi-strand steel strand cable vibration control system according to claim 5, characterized in that, Multiple binding straps (3) are used to wrap around the outer periphery of the sleeve (2). The multiple binding straps (3) are evenly spaced along the axial direction of the sleeve (2) to radially shrink the sleeve (2) and clamp it to the steel strand (1).

7. The construction method of a multi-strand steel strand cable vibration control system according to claim 1, characterized in that, In step S1, a mark is formed on the surface of the steel strand (1) by spraying.

8. The construction method of a multi-strand steel strand cable vibration control system according to claim 1, characterized in that, In step S2, after passing the lower anchor position at the marked position, the lifting is paused, and then the sleeve (2) is fitted and fixed.

9. The construction method of a multi-strand steel strand cable vibration control system according to claim 1, characterized in that, The multi-strand steel strand buckle vibration control system also includes a traction cable (6), which is connected to the steel strand (1) and lifted in step S2.

10. The construction method of a multi-strand steel strand cable vibration control system according to claim 1, characterized in that, The sleeve (2) is made of high-damping rubber material and is used to dissipate vibration energy through its own viscoelastic deformation when adjacent steel strands (1) vibrate relative to each other.

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